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166 results on '"K Boretzky"'

1. Spectroscopy of deeply bound orbitals in neutron-rich Ca isotopes

Author: P.J. Li, J. Lee, P. Doornenbal, S. Chen, S. Wang, A. Obertelli, Y. Chazono, J.D. Holt, B.S. Hu, K. Ogata, Y. Utsuno, K. Yoshida, N.L. Achouri, H. Baba, F. Browne, D. Calvet, F. Château, N. Chiga, A. Corsi, M.L. Cortés, A. Delbart, J.-M. Gheller, A. Giganon, A. Gillibert, C. Hilaire, T. Isobe, T. Kobayashi, Y. Kubota, V. Lapoux, H.N. Liu, T. Motobayashi, I. Murray, H. Otsu, V. Panin, N. Paul, W. Rodriguez, H. Sakurai, M. Sasano, D. Steppenbeck, L. Stuhl, Y.L. Sun, Y. Togano, T. Uesaka, K. Wimmer, K. Yoneda, O. Aktas, T. Aumann, K. Boretzky, C. Caesar, L.X. Chung, F. Flavigny, S. Franchoo, I. Gasparic, R.-B. Gerst, J. Gibelin, K.I. Hahn, J. Kahlbow, D. Kim, T. Koiwai, Y. Kondo, D. Körper, P. Koseoglou, C. Lehr, B.D. Linh, T. Lokotko, M. MacCormick, K. Miki, K. Moschner, T. Nakamura, S.Y. Park, D. Rossi, E. Sahin, F. Schindler, H. Simon, P.-A. Söderström, D. Sohler, S. Takeuchi, H. Toernqvist, J. Tscheuschner, V. Vaquero, V. Wagner, V. Werner, X. Xu, H. Yamada, D. Yan, Z. Yang, M. Yasuda, and L. Zanetti
Subjects: Unbound states, Knockout reaction, Single-particle strength, Shell evolution, Physics, QC1-999
Abstract: The calcium isotopes are an ideal system to investigate the evolution of shell structure and magic numbers. Although the properties of surface nucleons in calcium have been well studied, probing the structure of deeply bound nucleons remains a challenge. Here, we report on the first measurement of unbound states in 53Ca and 55Ca, populated from 54,56Ca(p,pn) reactions at a beam energy of around 216 MeV/nucleon at the RIKEN Radioactive Isotopes Beam Factory. The resonance properties, partial cross sections, and momentum distributions of these unbound states were analyzed. Orbital angular momentum l assignments were extracted from momentum distributions based on calculations using the distorted wave impulse approximation (DWIA) reaction model. The resonances at excitation energies of 5516(41)keV in 53Ca and 6000(250)keV in 55Ca indicate a significant l =3 component, providing the first experimental evidence for the ν0f7/2 single-particle strength of unbound hole states in the neutron-rich Ca isotopes. The observed excitation energies and cross-sections point towards extremely localized and well separated strength distributions, with some fragmentation for the ν0f7/2 orbital in 55Ca. These results are in good agreement with predictions from shell-model calculations using the effective GXPF1Bs interaction and ab initio calculations and diverge markedly from the experimental distributions in the nickel isotones at Z=28.
Published: 2024
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2. Measurement of nuclear interaction cross sections towards neutron-skin thickness determination

Author: L. Ponnath, T. Aumann, C.A. Bertulani, R. Gernhäuser, M. Heil, T. Almusidi, H. Alvarez-Pol, L. Atar, L. Atkins, Y. Ayyad, J. Benlliure, K. Boretzky, M.J.G. Borge, L.T. Bott, G. Bruni, B. Brückner, P. Cabanelas, C. Caesar, E. Casarejos, J. Cederkall, A. Corsi, D. Cortina-Gil, J.A. Dueñas, M. Duer, Z. Elekes, S. Escribano Rodriguez, L. Fabbietti, A. Falduto, M. Feijoo, M. Feijoo Fontan, L.M. Fonseca, A. Frotscher, D. Galaviz, E. Galiana, G. García-Jiménez, I. Gašparic̀, E.I. Geraci, A. Gillibert, B. Gnoffo, D. González Caamaño, A. Graña González, K. Göbel, A.-L. Hartig, A. Heinz, T. Hensel, M. Holl, A. Horvat, A. Jedele, D. Jelavic̀ Malenica, T. Jenegger, H.T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, A. Kelic-Heil, O.A. Kiselev, P. Klenze, D. Kresan, T. Kröll, E. Kudaibergenova, D. Kurtulgil, D. Körper, M. Labiche, C. Langer, I. Lihtar, Yu.A. Litvinov, B. Löher, J. Mayer, S. Murillo Morales, E. Nacher, T. Nilsson, A. Obertelli, V. Panin, J. Park, S. Paschalis, A. Perea, M. Petri, S. Pirrone, T. Pohl, R. Reifarth, H.-B. Rhee, J.L. Rodriguez-Sanchez, L. Rose, D.M. Rossi, P. Russotto, D. Savran, H. Scheit, H. Simon, S. Storck-Dutine, A.M. Stott, C. Sürder, R. Taniuchi, O. Tengblad, P. Teubig, L. Trache, M. Trimarchi, H.T. Törnqvist, L. Varga, V. Wagner, and F. Wamers
Subjects: Physics, QC1-999
Abstract: The accuracy of reaction theories used to extract properties of exotic nuclei from scattering experiments is often unknown or not quantified, but of utmost importance when, e.g., constraining the equation of state of asymmetric nuclear matter from observables as the neutron-skin thickness. In order to test the Glauber multiple-scattering model, the total interaction cross section of Image 1 on carbon targets was measured at initial beam energies of 400, 550, 650, 800, and 1000 MeV/nucleon. The measurements were performed during the first experiment of the newly constructed R3B (Reaction with Relativistic Radioactive Beams) experiment after the start of FAIR Phase-0 at the GSI/FAIR facility with beam energies of 400, 550, 650, 800, and 1000 MeV/nucleon. The combination of the large-acceptance dipole magnet GLAD and a newly designed and highly efficient Time-of-Flight detector enabled a precise transmission measurement with several target thicknesses for each initial beam energy with an experimental uncertainty of ±0.4%. A comparison with the Glauber model revealed a discrepancy of around 3.1% at higher beam energies, which will serve as a crucial baseline for the model-dependent uncertainty in future fragmentation experiments.
Published: 2024
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3. Constraining nucleon effective masses with flow and stopping observables from the SπRIT experiment

Author: C.Y. Tsang, M. Kurata-Nishimura, M.B. Tsang, W.G. Lynch, Y.X. Zhang, J. Barney, J. Estee, G. Jhang, R. Wang, M. Kaneko, J.W. Lee, T. Isobe, T. Murakami, D.S. Ahn, L. Atar, T. Aumann, H. Baba, K. Boretzky, J. Brzychczyk, G. Cerizza, N. Chiga, N. Fukuda, I. Gasparic, B. Hong, A. Horvat, K. Ieki, N. Inabe, Y.J. Kim, T. Kobayashi, Y. Kondo, P. Lasko, H.S. Lee, Y. Leifels, J. Łukasik, J. Manfredi, A.B. McIntosh, P. Morfouace, T. Nakamura, N. Nakatsuka, S. Nishimura, H. Otsu, P. Pawłowski, K. Pelczar, D. Rossi, H. Sakurai, C. Santamaria, H. Sato, H. Scheit, R. Shane, Y. Shimizu, H. Simon, A. Snoch, A. Sochocka, T. Sumikama, H. Suzuki, D. Suzuki, H. Takeda, S. Tangwancharoen, H. Törnqvist, Y. Togano, Z.G. Xiao, S.J. Yennello, and Y. Zhang
Subjects: Physics, QC1-999
Abstract: Properties of the nuclear equation of state (EoS) can be probed by measuring the dynamical properties of nucleus-nucleus collisions. In this study, we present the directed flow (v1), elliptic flow (v2) and stopping (VarXZ) measured in fixed target Sn + Sn collisions at Image 1 with the SπRIT Time Projection Chamber. We perform Bayesian analyses in which EoS parameters are varied simultaneously within the Improved Quantum Molecular Dynamics-Skyrme (ImQMD-Sky) transport code to obtain a multivariate correlated constraint. The varied parameters include symmetry energy, S0, and slope of the symmetry energy, L, at saturation density, isoscalar effective mass, ms⁎/mN, isovector effective mass, mv⁎/mN and the in-medium cross-section enhancement factor η. We find that the flow and VarXZ observables are sensitive to the splitting of proton and neutron effective masses and the in-medium cross-section. Comparisons of ImQMD-Sky predictions to the SπRIT data suggest a narrow range of preferred values for ms⁎/mN, mv⁎/mN and η.
Published: 2024
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4. Intruder configurations in 29Ne at the transition into the island of inversion: Detailed structure study of 28Ne

Author: H. Wang, M. Yasuda, Y. Kondo, T. Nakamura, J.A. Tostevin, K. Ogata, T. Otsuka, A. Poves, N. Shimizu, K. Yoshida, N.L. Achouri, H. Al Falou, L. Atar, T. Aumann, H. Baba, K. Boretzky, C. Caesar, D. Calvet, H. Chae, N. Chiga, A. Corsi, H.L. Crawford, F. Delaunay, A. Delbart, Q. Deshayes, Zs. Dombrádi, C. Douma, Z. Elekes, P. Fallon, I. Gašparić, J.-M. Gheller, J. Gibelin, A. Gillibert, M.N. Harakeh, A. Hirayama, C.R. Hoffman, M. Holl, A. Horvat, Á. Horváth, J.W. Hwang, T. Isobe, J. Kahlbow, N. Kalantar-Nayestanaki, S. Kawase, S. Kim, K. Kisamori, T. Kobayashi, D. Körper, S. Koyama, I. Kuti, V. Lapoux, S. Lindberg, F.M. Marqués, S. Masuoka, J. Mayer, K. Miki, T. Murakami, M.A. Najafi, K. Nakano, N. Nakatsuka, T. Nilsson, A. Obertelli, N.A. Orr, H. Otsu, T. Ozaki, V. Panin, S. Paschalis, A. Revel, D. Rossi, A.T. Saito, T. Saito, M. Sasano, H. Sato, Y. Satou, H. Scheit, F. Schindler, P. Schrock, M. Shikata, Y. Shimizu, H. Simon, D. Sohler, O. Sorlin, L. Stuhl, S. Takeuchi, M. Tanaka, M. Thoennessen, H. Törnqvist, Y. Togano, T. Tomai, J. Tscheuschner, J. Tsubota, T. Uesaka, Z. Yang, and K. Yoneda
Subjects: In-beam γ-ray spectroscopy, Island of inversion, Shell evolution, Physics, QC1-999
Abstract: Detailed γ-ray spectroscopy of the exotic neon isotope 28Ne has been performed for the first time using the one-neutron removal reaction from 29Ne on a liquid hydrogen target at 240 MeV/nucleon. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for 28Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder p-wave strength providing evidence of the breakdown of the N=20 and N=28 shell gaps. Only a weak, possible f-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large p-wave and small f-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain.
Published: 2023
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5. Unveiling the two-proton halo character of 17Ne: Exclusive measurement of quasi-free proton-knockout reactions

Author: C. Lehr, F. Wamers, F. Aksouh, Yu. Aksyutina, H. Álvarez-Pol, L. Atar, T. Aumann, S. Beceiro-Novo, C.A. Bertulani, K. Boretzky, M.J.G. Borge, C. Caesar, M. Chartier, A. Chatillon, L.V. Chulkov, D. Cortina-Gil, P. Díaz Fernández, H. Emling, O. Ershova, L.M. Fraile, H.O.U. Fynbo, D. Galaviz, H. Geissel, M. Heil, M. Heine, D.H.H. Hoffmann, M. Holl, H.T. Johansson, B. Jonson, C. Karagiannis, O.A. Kiselev, J.V. Kratz, R. Kulessa, N. Kurz, C. Langer, M. Lantz, T. Le Bleis, R. Lemmon, Yu.A. Litvinov, B. Löher, K. Mahata, J. Marganiec-Galązka, C. Müntz, T. Nilsson, C. Nociforo, W. Ott, V. Panin, S. Paschalis, A. Perea, R. Plag, R. Reifarth, A. Richter, K. Riisager, C. Rodriguez-Tajes, D. Rossi, D. Savran, H. Scheit, G. Schrieder, P. Schrock, H. Simon, J. Stroth, K. Sümmerer, O. Tengblad, H. Weick, and C. Wimmer
Subjects: Physics, QC1-999
Abstract: The proton drip-line nucleus 17Ne is investigated experimentally in order to determine its two-proton halo character. A fully exclusive measurement of the 17Ne(p,2p)16F→15⁎O+p quasi-free one-proton knockout reaction has been performed at GSI at around 500 MeV/nucleon beam energy. All particles resulting from the scattering process have been detected. The relevant reconstructed quantities are the angles of the two protons scattered in quasi-elastic kinematics, the decay of 16F into 15O (including γ decays from excited states) and a proton, as well as the 15O+p relative-energy spectrum and the 16F momentum distributions. The latter two quantities allow an independent and consistent determination of the fractions of l=0 and l=2 motion of the valence protons in 17Ne. With a resulting relatively small l=0 component of only around 35(3)%, it is concluded that 17Ne exhibits a rather modest halo character only. The quantitative agreement of the two values deduced from the energy spectrum and the momentum distributions supports the theoretical treatment of the calculation of momentum distributions after quasi-free knockout reactions at high energies by taking into account distortions based on the Glauber theory. Moreover, the experimental data allow the separation of valence-proton knockout and knockout from the 15O core. The latter process contributes with 11.8(3.1) mb around 40% to the total proton-knockout cross section of 30.3(2.3) mb, which explains previously reported contradicting conclusions derived from inclusive cross sections.
Published: 2022
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6. Rapidity distributions of Z = 1 isotopes and the nuclear symmetry energy from Sn+Sn collisions with radioactive beams at 270 MeV/nucleon

Author: M. Kaneko, T. Murakami, T. Isobe, M. Kurata-Nishimura, A. Ono, N. Ikeno, J. Barney, G. Cerizza, J. Estee, G. Jhang, J.W. Lee, W.G. Lynch, C. Santamaria, C.Y. Tsang, M.B. Tsang, R. Wang, D.S. Ahn, L. Atar, T. Aumann, H. Baba, K. Boretzky, J. Brzychczyk, N. Chiga, N. Fukuda, I. Gašparić, B. Hong, A. Horvat, T. Ichihara, K. Ieki, N. Inabe, Y.J. Kim, T. Kobayashi, Y. Kondo, P. Lasko, H.S. Lee, Y. Leifels, J. Łukasik, J. Manfredi, A.B. McIntosh, P. Morfouace, T. Nakamura, N. Nakatsuka, S. Nishimura, R. Olsen, H. Otsu, P. Pawłowski, K. Pelczar, D. Rossi, H. Sakurai, H. Sato, H. Scheit, R. Shane, Y. Shimizu, H. Simon, T. Sumikama, D. Suzuki, H. Suzuki, H. Takeda, S. Tangwancharoen, Y. Togano, H. Törnqvist, Z. Xiao, S.J. Yennello, J. Yurkon, and Y. Zhang
Subjects: Heavy radioactive isotope collisions, Cluster productions, Nuclear symmetry energy, Antisymmetrized molecular dynamics, Physics, QC1-999
Abstract: The rapidity distributions of hydrogen isotopes emitted from central collisions of neutron-rich 132Sn+124Sn and neutron-deficient 108Sn+112Sn systems at 270 MeV/nucleon were investigated at RIKEN-RIBF. The data are compared with antisymmetrized molecular dynamics (AMD) calculations and the rapidity distributions can be reproduced after adjusting the in-medium nucleon-nucleon cross sections. The double ratios between the two reaction systems taken for the relative yields of deuteron to proton (d/p) and triton to proton (t/p) are further examined in the midrapidity domain, where the adjustments in the AMD calculations do not affect much on them. The d/p and t/p double ratios at midrapidity agree well with the ratio of the system neutron numbers and its squared value, respectively, and the rapidity dependence of these double ratios is consistent with a picture of partial mixing of colliding nuclei. By comparing with the AMD model which shows a strong symmetry energy dependence of the t/p double ratio, the experimental result in the midrapidity domain favors the calculation with a symmetry-energy slope parameter around L=46 MeV rather than L=108 MeV.
Published: 2021
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7. Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range

Author: M. Holl, V. Panin, H. Alvarez-Pol, L. Atar, T. Aumann, S. Beceiro-Novo, J. Benlliure, C.A. Bertulani, J.M. Boillos, K. Boretzky, M. Caamaño, C. Caesar, E. Casarejos, W. Catford, J. Cederkall, L. Chulkov, D. Cortina-Gil, E. Cravo, I. Dillmann, P. Díaz Fernández, Z. Elekes, J. Enders, L.M. Fraile, D. Galaviz Redondo, R. Gernhäuser, P. Golubev, T. Heftrich, M. Heil, M. Heine, A. Heinz, A. Henriques, H.T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, T. Kröll, N. Kurz, C. Langer, T. Le Bleis, S. Lindberg, J. Machado, E. Nacher, M.A. Najafi, T. Nilsson, C. Nociforo, S. Paschalis, M. Petri, R. Reifarth, G. Ribeiro, C. Rigollet, D.M. Rossi, D. Savran, H. Scheit, H. Simon, O. Sorlin, I. Syndikus, O. Tengblad, Y. Togano, M. Vandebrouck, P. Velho, F. Wamers, H. Weick, C. Wheldon, G.L. Wilson, J.S. Winfield, P. Woods, M. Zhukov, and K. Zuber
Subjects: Physics, QC1-999
Abstract: The quasi-free scattering reactions 11C(p,2p) and 10,11,12C(p,pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and proton-neutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p,2p) and 12C(p,pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of single-particle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p,2p) are found to be 'significantly smaller than for (p,pn) reactions for all investigated nuclei. Keywords: Quasi-free scattering, Inverse kinematics, Shell model, Spectroscopic factors
Published: 2019
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8. Symmetry energy investigation with pion production from Sn+Sn systems

Author: G. Jhang, J. Estee, J. Barney, G. Cerizza, M. Kaneko, J.W. Lee, W.G. Lynch, T. Isobe, M. Kurata-Nishimura, T. Murakami, C.Y. Tsang, M.B. Tsang, R. Wang, D.S. Ahn, L. Atar, T. Aumann, H. Baba, K. Boretzky, J. Brzychczyk, N. Chiga, N. Fukuda, I. Gasparic, B. Hong, A. Horvat, K. Ieki, N. Inabe, Y.J. Kim, T. Kobayashi, Y. Kondo, P. Lasko, H.S. Lee, Y. Leifels, J. Łukasik, J. Manfredi, A.B. McIntosh, P. Morfouace, T. Nakamura, N. Nakatsuka, S. Nishimura, R. Olsen, H. Otsu, P. Pawłowski, K. Pelczar, D. Rossi, H. Sakurai, C. Santamaria, H. Sato, H. Scheit, R. Shane, Y. Shimizu, H. Simon, A. Snoch, A. Sochocka, Z. Sosin, T. Sumikama, H. Suzuki, D. Suzuki, H. Takeda, S. Tangwancharoen, H. Toernqvist, Y. Togano, Z.G. Xiao, S.J. Yennello, J. Yurkon, Y. Zhang, Maria Colonna, Dan Cozma, Paweł Danielewicz, Hannah Elfner, Natsumi Ikeno, Che Ming Ko, Justin Mohs, Dmytro Oliinychenko, Akira Ono, Jun Su, Yong Jia Wang, Hermann Wolter, Jun Xu, Ying-Xun Zhang, and Zhen Zhang
Subjects: Physics, QC1-999
Abstract: In the past two decades, pions created in the high density regions of heavy ion collisions have been predicted to be sensitive at high densities to the symmetry energy term in the nuclear equation of state, a property that is key to our understanding of neutron stars. In a new experiment designed to study the symmetry energy, the multiplicities of negatively and positively charged pions have been measured with high accuracy for central 132Sn+124Sn, 112Sn+124Sn, and 108Sn+112Sn collisions at E/A=270 MeV with the SπRIT Time Projection Chamber. While individual pion multiplicities are measured to 4% accuracy, those of the charged pion multiplicity ratios are measured to 2% accuracy. We compare these data to predictions from seven major transport models. The calculations reproduce qualitatively the dependence of the multiplicities and their ratios on the total neutron and proton number in the colliding systems. However, the predictions of the transport models from different codes differ too much to allow extraction of reliable constraints on the symmetry energy from the data. This finding may explain previous contradictory conclusions on symmetry energy constraints obtained from pion data in Au+Au system. These new results call for still better understanding of the differences among transport codes, and new observables that are more sensitive to the density dependence of the symmetry energy.
Published: 2021
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9. Probing the Z = 6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions

Author: I. Syndikus, M. Petri, A.O. Macchiavelli, S. Paschalis, C.A. Bertulani, T. Aumann, H. Alvarez-Pol, L. Atar, S. Beceiro-Novo, J. Benlliure, J.M. Boillos, K. Boretzky, M.J.G. Borge, B.A. Brown, M. Caamaño, C. Caesar, E. Casarejos, W. Catford, J. Cederkall, S. Chakraborty, L.V. Chulkov, D. Cortina-Gil, E. Cravo, R. Crespo, U. Datta Pramanik, I. Dillmann, P. Díaz Fernández, Z. Elekes, J. Enders, F. Farinon, L.M. Fraile, D. Galaviz, H. Geissel, R. Gernhäuser, P. Golubev, K. Göbel, M. Heil, M. Heine, A. Heinz, A. Henriques, M. Holl, H.T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, T. Kröll, N. Kurz, C. Langer, T. Le Bleis, J. Machado, J. Marganiec-Gałązka, E. Nacher, T. Nilsson, C. Nociforo, V. Panin, A. Perea, S.B. Pietri, R. Plag, A. Rahaman, R. Reifarth, A. Revel, G. Ribeiro, C. Rigollet, D.M. Rossi, D. Savran, H. Scheit, H. Simon, O. Sorlin, O. Tengblad, Y. Togano, M. Vandebrouck, V. Volkov, F. Wamers, C. Wheldon, G.L. Wilson, J.S. Winfield, H. Weick, P. Woods, D. Yakorev, M. Zhukov, A. Zilges, and K. Zuber
Subjects: Quasi-free scattering reactions, Magic numbers, Spin-orbit splitting, Tensor force, Shell evolution, Exotic nuclei, Physics, QC1-999
Abstract: The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 21+ state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton 1p1/2−1p3/2 spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline.
Published: 2020
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10. Study of Δ excitations in medium-mass nuclei with peripheral heavy ion charge-exchange reactions

Author: J.L. Rodríguez-Sánchez, J. Benlliure, I. Vidaña, H. Lenske, C. Scheidenberger, J. Vargas, H. Alvarez-Pol, J. Atkinson, T. Aumann, Y. Ayyad, S. Beceiro-Novo, K. Boretzky, M. Caamaño, E. Casarejos, D. Cortina-Gil, P. Díaz Fernández, A. Estrade, H. Geissel, E. Haettner, A. Kelić-Heil, Yu.A. Litvinov, C. Paradela, D. Pérez-Loureiro, S. Pietri, A. Prochazka, M. Takechi, Y.K. Tanaka, H. Weick, and J.S. Winfield
Subjects: Baryon resonances, Inverse kinematics, Fragment separator FRS, Physics, QC1-999
Abstract: Isobaric single charge-exchange reactions, changing nuclear charges by one unit but leaving the mass partitions unaffected, have been for the first time investigated by peripheral collisions of 112Sn ions accelerated up to 1A GeV at the GSI facilities. The high-resolving power of the FRS spectrometer allows us to obtain (p,n)-type isobaric charge-exchange cross sections with an uncertainty of 3.5% and to separate quasi-elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic component is associated to the excitation of the Δ(1232) isobar resonance and the emission of pions in s-wave both in the target and projectile nucleus, while the quasi-elastic contribution is associated to the nuclear spin-isospin response of nucleon-hole excitations. An apparent shift of the Δ-resonance peak of ∼63 MeV is observed when comparing the missing-energy spectra obtained from the measurements with proton and carbon targets. A detailed analysis, performed with a theoretical model for the reactions, indicates that this observation can be simply interpreted as a change in the relative magnitude between the contribution of the excitation of the resonance in the target and in the projectile.
Published: 2020
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11. Quasi-free proton knockout from 12C on carbon target at 398 MeV/u

Author: V. Panin, M. Holl, J.T. Taylor, Y. Aksyutina, H. Alvarez-Pol, T. Aumann, C.A. Bertulani, K. Boretzky, C. Caesar, M. Chartier, L.V. Chulkov, D. Cortina-Gil, J. Enders, O. Ershova, H. Geissel, R. Gernhäuser, M. Heil, H.T. Johansson, B. Jonson, A. Kelić-Heil, O. Kiselev, C. Langer, T. Le Bleis, R. Lemmon, T. Nilsson, S. Paschalis, M. Petri, R. Plag, R. Reifarth, D. Rossi, H. Scheit, H. Simon, F. Wamers, H. Weick, and C. Wimmer
Subjects: Physics, QC1-999
Abstract: The proton-removal mechanism of the 12C→11B reaction induced on a carbon target via elementary nucleon-nucleon scattering is investigated in exclusive triple-coincidence measurements. The observed two-nucleon angular correlations are found to be consistent with quasi-free scattering of a projectile-like proton off a target-like nucleon. Exclusive cross sections for one-step pp and pn interactions are determined as σpp=17.2(12) mb and σpn=18.2(18), respectively. The extracted quasi-free component amounts up to 58(4)% of the total proton-removal cross section. The results are compared to total proton-removal cross sections obtained from the experiment and eikonal reaction theory. Keywords: Direct nuclear reactions, One-nucleon removal, Quasi-free scattering, Cross sections
Published: 2019
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12. Coulomb and nuclear excitations of narrow resonances in 17Ne

Author: J. Marganiec, F. Wamers, F. Aksouh, Yu. Aksyutina, H. Álvarez-Pol, T. Aumann, S. Beceiro-Novo, C.A. Bertulani, K. Boretzky, M.J.G. Borge, M. Chartier, A. Chatillon, L.V. Chulkov, D. Cortina-Gil, H. Emling, O. Ershova, L.M. Fraile, H.O.U. Fynbo, D. Galaviz, H. Geissel, M. Heil, D.H.H. Hoffmann, J. Hoffmann, H.T. Johansson, B. Jonson, C. Karagiannis, O.A. Kiselev, J.V. Kratz, R. Kulessa, N. Kurz, C. Langer, M. Lantz, T. Le Bleis, R. Lemmon, Yu.A. Litvinov, K. Mahata, C. Müntz, T. Nilsson, C. Nociforo, G. Nyman, W. Ott, V. Panin, S. Paschalis, A. Perea, R. Plag, R. Reifarth, A. Richter, C. Rodriguez-Tajes, D. Rossi, K. Riisager, D. Savran, G. Schrieder, H. Simon, J. Stroth, K. Sümmerer, O. Tengblad, S. Typel, H. Weick, M. Wiescher, and C. Wimmer
Subjects: Physics, QC1-999
Abstract: New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the O15+p+p three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.
Published: 2016
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13. Exclusive measurements of quasi-free proton scattering reactions in inverse and complete kinematics

Author: V. Panin, J.T. Taylor, S. Paschalis, F. Wamers, Y. Aksyutina, H. Alvarez-Pol, T. Aumann, C.A. Bertulani, K. Boretzky, C. Caesar, M. Chartier, L.V. Chulkov, D. Cortina-Gil, J. Enders, O. Ershova, H. Geissel, R. Gernhäuser, M. Heil, H.T. Johansson, B. Jonson, A. Kelić-Heil, C. Langer, T. Le Bleis, R. Lemmon, T. Nilsson, M. Petri, R. Plag, R. Reifarth, D. Rossi, H. Scheit, H. Simon, H. Weick, and C. Wimmer
Subjects: Quasi-free scattering, Inverse kinematics, Single-particle states, Spectroscopic factors, Physics, QC1-999
Abstract: Quasi-free scattering reactions of the type (p,2p) were measured for the first time exclusively in complete and inverse kinematics, using a 12C beam at an energy of ∼400 MeV/u as a benchmark. This new technique has been developed to study the single-particle structure of exotic nuclei in experiments with radioactive-ion beams. The outgoing pair of protons and the fragments were measured simultaneously, enabling an unambiguous identification of the reaction channels and a redundant measurement of the kinematic observables. Both valence and deeply-bound nucleon orbits are probed, including those leading to unbound states of the daughter nucleus. Exclusive (p,2p) cross sections of 15.8(18) mb, 1.9(2) mb and 1.5(2) mb to the low-lying 0p-hole states overlapping with the ground state (3/2−) and with the bound excited states of 11B at 2.125 MeV (1/2−) and 5.02 MeV (3/2−), respectively, were determined via γ-ray spectroscopy. Particle-unstable deep-hole states, corresponding to proton removal from the 0s-orbital, were studied via the invariant-mass technique. Cross sections and momentum distributions were extracted and compared to theoretical calculations employing the eikonal formalism. The obtained results are in a good agreement with this theory and with direct-kinematics experiments. The dependence of the proton–proton scattering kinematics on the internal momentum of the struck proton and on its separation energy was investigated for the first time in inverse kinematics employing a large-acceptance measurement.
Published: 2016
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14. Observation of isoscalar multipole strengths in exotic doubly-magic 56Ni in inelastic α scattering in inverse kinematics

Author: S. Bagchi, J. Gibelin, M.N. Harakeh, N. Kalantar-Nayestanaki, N.L. Achouri, H. Akimune, B. Bastin, K. Boretzky, H. Bouzomita, M. Caamaño, L. Càceres, S. Damoy, F. Delaunay, B. Fernández-Domínguez, M. Fujiwara, U. Garg, G.F. Grinyer, O. Kamalou, E. Khan, A. Krasznahorkay, G. Lhoutellier, J.F. Libin, S. Lukyanov, K. Mazurek, M.A. Najafi, J. Pancin, Y. Penionzhkevich, L. Perrot, R. Raabe, C. Rigollet, T. Roger, S. Sambi, H. Savajols, M. Senoville, C. Stodel, L. Suen, J.C. Thomas, M. Vandebrouck, and J. Van de Walle
Subjects: Physics, QC1-999
Abstract: The Isoscalar Giant Monopole Resonance (ISGMR) and the Isoscalar Giant Dipole Resonance (ISGDR) compression modes have been studied in the doubly-magic unstable nucleus 56Ni. They were measured by inelastic α-particle scattering in inverse kinematics at 50 MeV/u with the MAYA active target at the GANIL facility. The centroid of the ISGMR has been obtained at Ex=19.1±0.5 MeV. Evidence for the low-lying part of the ISGDR has been found at Ex=17.4±0.7 MeV. The strength distribution for the dipole mode shows similarity with the prediction from the Hartree–Fock (HF) based random-phase approximation (RPA) [1]. These measurements confirm inelastic α-particle scattering as a suitable probe for exciting the ISGMR and the ISGDR modes in radioactive isotopes in inverse kinematics.
Published: 2015
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15. Isoscaling in central Sn+Sn collisions at 270 MeV/u

Author: J. W. Lee, M. B. Tsang, C. Y. Tsang, R. Wang, J. Barney, J. Estee, T. Isobe, M. Kaneko, M. Kurata-Nishimura, W. G. Lynch, T. Murakami, A. Ono, S. R. Souza, D. S. Ahn, L. Atar, T. Aumann, H. Baba, K. Boretzky, J. Brzychczyk, G. Cerizza, N. Chiga, N. Fukuda, I. Gasparic, B. Hong, A. Horvat, K. Ieki, N. Ikeno, N. Inabe, G. Jhang, Y. J. Kim, T. Kobayashi, Y. Kondo, P. Lasko, H. S. Lee, Y. Leifels, J. Łukasik, J. Manfredi, A. B. McIntosh, P. Morfouace, T. Nakamura, N. Nakatsuka, S. Nishimura, H. Otsu, P. Pawłowski, K. Pelczar, D. Rossi, H. Sakurai, C. Santamaria, H. Sato, H. Scheit, R. Shane, Y. Shimizu, H. Simon, A. Snoch, A. Sochocka, T. Sumikama, H. Suzuki, D. Suzuki, H. Takeda, S. Tangwancharoen, Y. Togano, Z. G. Xiao, S. J. Yennello, Y. Zhang, and (the S π RIT collaboration)
Subjects: Nuclear Theory (nucl-th), Nuclear and High Energy Physics, Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment, Heavy radioactive isotope collisions, Cluster productions, Nuclear symmetry energy, Antisymmetrized molecular dynamics
Abstract: Experimental information on fragment emissions is important in understanding the dynamics of nuclear collisions and in the development of transport model simulating heavy-ion collisions. The composition of complex fragments emitted in the heavy-ion collisions can be explained by statistical models, which assume that thermal equilibrium is achieved at collision energies below 100 MeV/u. Our new experimental data together with theoretical analyses for light particles from Sn+Sn collisions at 270 MeV/u, suggest that the hypothesis of thermal equilibrium breaks down for particles emitted with high transfer momentum. To inspect the system's properties in such limit, the scaling features of the yield ratios of particles from two systems, a neutron-rich system of ${}^{132}\mathrm{Sn}+{}^{124}\mathrm{Sn}$ and a nearly symmetric system of ${}^{108}\mathrm{Sn}+{}^{112}\mathrm{Sn}$, are examined in the framework of the statistical multifragmentation model and the antisymmetrized molecular dynamics model. The isoscaling from low energy particles agree with both models. However the observed breakdown of isoscaling for particles with high transverse momentum cannot be explained by the antisymmetrized molecular dynamics model.
Published: 2022
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16. Observation of a correlated free four-neutron system

Author: M. Duer, T. Aumann, R. Gernhäuser, V. Panin, S. Paschalis, D. M. Rossi, N. L. Achouri, D. Ahn, H. Baba, C. A. Bertulani, M. Böhmer, K. Boretzky, C. Caesar, N. Chiga, A. Corsi, D. Cortina-Gil, C. A. Douma, F. Dufter, Z. Elekes, J. Feng, B. Fernández-Domínguez, U. Forsberg, N. Fukuda, I. Gasparic, Z. Ge, J. M. Gheller, J. Gibelin, A. Gillibert, K. I. Hahn, Z. Halász, M. N. Harakeh, A. Hirayama, M. Holl, N. Inabe, T. Isobe, J. Kahlbow, N. Kalantar-Nayestanaki, D. Kim, S. Kim, T. Kobayashi, Y. Kondo, D. Körper, P. Koseoglou, Y. Kubota, I. Kuti, P. J. Li, C. Lehr, S. Lindberg, Y. Liu, F. M. Marqués, S. Masuoka, M. Matsumoto, J. Mayer, K. Miki, B. Monteagudo, T. Nakamura, T. Nilsson, A. Obertelli, N. A. Orr, H. Otsu, S. Y. Park, M. Parlog, P. M. Potlog, S. Reichert, A. Revel, A. T. Saito, M. Sasano, H. Scheit, F. Schindler, S. Shimoura, H. Simon, L. Stuhl, H. Suzuki, D. Symochko, H. Takeda, J. Tanaka, Y. Togano, T. Tomai, H. T. Törnqvist, J. Tscheuschner, T. Uesaka, V. Wagner, H. Yamada, B. Yang, L. Yang, Z. H. Yang, M. Yasuda, K. Yoneda, L. Zanetti, J. Zenihiro, M. V. Zhukov, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Research unit Nuclear & Hadron Physics, and Nuclear Energy
Subjects: Multidisciplinary, Nuclear Force, Nuclear Structure, Tetraneutron, Reactions with Radioactive Beams, Physics, ddc:500, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract: Nature 606(7915), 678 - 682 (2022). doi:10.1038/s41586-022-04827-6, Published by Nature Publ. Group, London [u.a.]
Published: 2022
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17. Systematic study of {\Delta}(1232) resonance excitations using single isobaric charge-exchange reactions induced by medium-mass projectiles of Sn

Author: J. L. Rodríguez-Sánchez, J. Benlliure, I. Vidaña, H. Lenske, J. Vargas, C. Scheidenberger, H. Alvarez-Pol, J. Atkinson, T. Aumann, Y. Ayyad, S. Beceiro-Novo, K. Boretzky, M. Caamaño, E. Casarejos, D. Cortina-Gil, P. Díaz Fernández, A. Estrade, H. Geissel, E. Haettner, A. Kelić-Heil, Yu. A. Litvinov, C. Paradela, D. Pérez-Loureiro, S. Pietri, A. Prochazka, M. Takechi, Y. K. Tanaka, H. Weick, and J. S. Winfield
Subjects: Nuclear Theory, Nuclear Experiment
Abstract: The fragment separator FRS has been for the first time used to measure the (n,p) and (p,n)-type isobaric charge-exchange cross sections of stable 112,124Sn isotopes accelerated at 1A GeV with an uncertainty of 3% and to separate quasi-elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic contribution can be associated to the excitation of isobar {\Delta}(1232) resonances and to the pion emission in s-wave, both in the target and projectile nuclei, while the quasi-elastic contribution is associated to the nuclear spin-isospin response of nucleon-hole excitations. The data lead to interesting results where we observe a clear quenching of the quasi-elastic component and their comparisons to theoretical calculations demonstrate that the baryonic resonances can be excited in the target and projectile nuclei. To go further in this investigation, we propose to study the excitation of baryonic resonances taking advantage of the combination of high-resolving power magnetic spectrometers with the WASA calorimeter. These new measurements will allow us to determine the momenta of the ejectiles and pions emitted in coincidence after the single isobaric charge-exchange collisions, providing us unique opportunities to study the evolution of the baryonic resonance dynamics with the neutron-proton asymmetry through the use of exotic radioactive ion beams., Comment: 14 pages, 9 figures. arXiv admin note: text overlap with arXiv:2004.06404
Published: 2021

18. Neutron capture cross sections of light neutron-rich nuclei relevant for r-process nucleosynthesis

Author: M. Heine, Th. Kröll, S. Chakraborty, Rene Reifarth, Stefan Typel, P. Díaz Fernández, D. M. Rossi, Ushasi Datta, Marielle Chartier, Ralf Plag, J. Marganiec, A. Bhattacharyya, Catherine Rigollet, Christoph Langer, V. Panin, M. V. Ricciardi, C. Nociforo, P. Das, R. Krücken, Yvonne Leifels, S. Beceiro-Novo, Herbert A. Simon, Anisur Rahaman, C. Caesar, H. Geissel, J. S. Winfield, Andreas Wagner, Nasser Kalantar-Nayestanaki, Björn Jonson, H. Emling, T. Le Bleis, W. N. Catford, Thomas Aumann, D. Cortina-Gil, Stefanos Paschalis, Yasuhiro Togano, G. Münzenberg, Yutaka Utsuno, C. Scheidenberger, Helmut Weick, Håkan T Johansson, H. Scheit, D. González-Díaz, J. Kurcewicz, K. Boretzky, G. De. Angelis, B. V. Carlson, Thomas Nilsson, F. Wamers, Nuclear Energy, Institut Pluridisciplinaire Hubert Curien (IPHC), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Neutron capture, 010308 nuclear & particles physics, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, r-process nucleosynthesis, Dissociation (chemistry), Nuclear physics, Reaction rate, Nucleosynthesis, neutron-rich nuclei, 0103 physical sciences, Neutron cross section, r-process, Neutron, Hauser-Feshbach, 010306 general physics, Ground state, Nuclear Experiment
Abstract: International audience; The measurements of neutron capture cross sections of neutron-rich nuclei are challenging but essential for understanding nucleosynthesis and stellar evolution processes in the explosive burning scenario. In the quest of r-process abundances, according to the neutrino-driven-wind model, light neutron-rich unstable nuclei may play a significant role as seed nuclei that influence the abundance pattern. Hence, experimental data for neutron capture cross sections of neutron-rich nuclei are needed. Coulomb dissociation of radioactive ion beams at intermediate energy is a powerful indirect method for inferring capture cross section. As a test case for validation of the indirect method, the neutron capture cross section (n, γ) for C14 was inferred from the Coulomb dissociation of C15 at intermediate energy (600A MeV). A comparison between different theoretical approaches and experimental results for the reaction is discussed. We report for the first time experimental reaction cross sections of Na28(n,γ)Na29, Na29(n,γ)Na30, Mg32(n,γ)Mg33, and Al34(n,γ)Al35. The reaction cross sections were inferred indirectly through Coulomb dissociation of Na29,30, Mg33, and Al35 at incident projectile energies around 400–430 A MeV using the FRS-LAND setup at GSI, Darmstadt. The neutron capture cross sections were obtained from the photoabsorption cross sections with the aid of the detailed balance theorem. The reaction rates for the neutron-rich Na, Mg, Al nuclei at typical r-process temperatures were obtained from the measured (n,γ) capture cross sections. The measured neutron capture reaction rates of the neutron-rich nuclei, Na28, Na29, and Al34 are significantly lower than those predicted by the Hauser-Feshbach decay model. A similar trend was observed earlier for C17 and N19 but in the case of C14(n,γ)C15 the trend is opposite. The situation is more complicated when the ground state has a multi-particle-hole configuration. For Mg32, the measured cross section is about 40–90% higher than the Hauser-Feshbach prediction.
Published: 2021
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19. Investigation of background reduction techniques for the NeuLAND neutron detector

Author: Nasser Kalantar-Nayestanaki, D. Kresan, I. Gasparic, Catherine Rigollet, J. Mayer, K. Boretzky, C. A. Douma, and Research unit Nuclear & Hadron Physics
Subjects: Physics, Nuclear and High Energy Physics, Scintillation, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, NeuLAND, Detector, Monte Carlo method, Neutron detection, VETO, Background elimination, Scintillator, 01 natural sciences, Charged particle, Neutron temperature, Nuclear physics, 0103 physical sciences, Neutron, Nuclear Experiment, 010306 general physics, Instrumentation, R3B, R 3 B
Abstract: NeuLAND is the neutron detector used by the R3B collaboration, which is part of the NUSTAR collaboration at the FAIR facility. NeuLAND is used for the detection of fast neutrons in the range of 200 MeV- 1000 MeV and is composed of plastic scintillators. Neutrons can undergo hadronic scattering with the scintillator material to produce charged particles, which in turn can be detected by their scintillation light. The high granularity of the detector allows for an accurate reconstruction of the primary interaction points of the neutrons. With these interaction points and with the information from the other detectors in the R3B setup, the reaction at the target can be kinematically reconstructed. This reconstruction is the tool that enables the R3B collaboration to study complex reactions. However, particles produced through reactions of the incoming radioactive beam with other R3B detectors may also enter NeuLAND’s active volume and generate a significant background. In this paper, Monte Carlo simulations are utilized to explore possible reduction techniques of this background. In particular, the reduction of the charged-particle component of this background through the use of a VETO wall is explored for the initial setup of the R3B experiment. The list of physics processes considered and their implementation in the simulations are tested against experimental data to ensure that conclusions about the background reduction are meaningful. Extensive simulations show that the use of a VETO wall is, in many situations, not necessary.
Published: 2019
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20. Experimental Study of $^{4}n$ by Directly Detecting the Decay Neutrons

Author: Atsumi Saito, Yohei Shimizu, H. Törnqvist, B. Monteagudo, T. Isobe, M. Caamaño, H. Scheit, S. Kiyotake, J. Tscheuschner, M. L. Cortés, F. M. Marqués, N. Fukuda, N. A. Orr, J. M. Gheller, A. Gillibert, A. Matta, K. Yoneda, L. Stuhl, Z. Elekes, I. Kuti, V. Wagner, M. Miwa, Z. Halász, A. Obertelli, S. Kim, A. Revel, L. Zanetti, N. L. Achouri, S. Takeuchi, F. Dufter, C. A. Douma, S. Masuoka, Stefanos Paschalis, R. Gernhäuser, S. Chen, Nobuyuki Chiga, S. Storck, T. Shimada, M.N. Harakeh, P. Koseoglou, T. Harada, B. Yang, M. Matsumoto, H. Takeda, D. S. Ahn, Yuya Kubota, H. Yamada, Yasuhiro Togano, A. Hirayama, Y. Yasuda, T. Fujino, D. M. Rossi, Nasser Kalantar-Nayestanaki, J. Tanaka, M. Böhmer, N. Inabe, Didier Beaumel, S. Park, Thomas Aumann, H. Baba, Tomohiro Uesaka, F. Schindler, J. Feng, Zaihong Yang, I. Murray, Julien Gibelin, K. Boretzky, S. W. Huang, B. Fernández-Domínguez, S. Reichert, Takashi Nakamura, Yu-xin Liu, K. Wimmer, Yukie Maeda, L. Yang, H. Sato, E. Tronchin, P. Doornenbal, Dmytro Symochko, D. Cortina, J. Kahlbow, S. Shimoura, H. Suzuki, Hideaki Otsu, M. Potlog, P. J. Li, J. Mayer, H. Miki, Masaki Sasano, Toshio Kobayashi, Z. Ge, D. Kim, Juzo Zenihiro, T. Tomai, I. Stefan, M. Parlog, H. Simon, V. Panin, Igor Gašparić, C. Lehr, Yosuke Kondo, C. Lenain, U. Forsberg, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Research unit Nuclear & Hadron Physics, and Nuclear Energy
Subjects: Nuclear structure and force, tetraneutron, direct reactions, radioactive beams, Physics, Nuclear physics, 010308 nuclear & particles physics, 0103 physical sciences, Tetraneutron, Neutron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010306 general physics, 01 natural sciences, Atomic and Molecular Physics, and Optics, 3. Good health
Abstract: The tetraneutron has attracted the attention of nuclear physicists during the past decades, but there is still no unambiguous confirmation of its existence or non-existence. A new experiment based on $$^{8}$$ He(p, 2p) $$^{7}$$ H{t+ $$^{4}n$$ } reaction, with direct detection of the four neutrons, has been carried out at RIBF, which can hopefully help to draw a definite conclusion on the tetraneutron system.
Published: 2021
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21. Unperturbed inverse kinematics nucleon knockout measurements with a carbon beam

Author: S. Morozov, T. Atovullaev, O. Gavrischuk, I. Rufanov, D. M. Rossi, I. Slepnev, V. Tcholakov, V. Zhezher, Yu. Potrebenikov, E.P. Segarra, A. Timoshenko, A. Taranenko, A. Corsi, A. Shutov, D. Blaschke, A. Terletsky, G. Musulmanbekov, A. Kuznetsov, A. Vishnevsky, Herbert A. Simon, V. Vasendina, E. Piasetzky, V. Lenivenko, R. Kattabekov, D. Sakulin, A. Dmitriev, S. Lobastov, P. Dulov, Yu. Ivanova, O. Warmusz, N. Topilin, V. Rogov, M. Duer, P. Senger, V. Spaskov, D. Suvarieva, A. Morozov, Alexander Schmidt, N. Lashmanov, Kh. U. Abraamyan, I. Slepov, K. Gertsenberger, N. Zamiatin, D. Baranov, M. Strikhanov, V. Yurevich, K. Boretzky, V. Babkin, V. Samsonov, G. Agakishiev, N. Karpushkin, D. Bogoslovsky, V. Kekelidze, D. Peresunko, Y.-G. Ma, I. Filippov, A. Ciszewski, A. Ivashkin, D. Egorov, B. Topko, A. Zinchenko, M. Patsyuk, V. Shumikhin, V. Plotnikov, O. Petukhov, S. Bazylev, V. Shutov, Carlos A. Bertulani, M. Buryakov, A. Fediunin, V. Tikhomirov, E. Litvinenko, A. Makankin, I. Korover, D. Blau, S. Khabarov, Yu. Kiryushin, S. Piyadin, A. Stavinskiy, V. Kolesnikov, D. Finogeev, A. Kovalenko, M. Golubeva, M. Kapishin, A. Chebotov, D. Nikitin, A. Dryablov, J. Tanaka, Oleg B. Tarasov, Igor Gašparić, S. Kakurin, Or Hen, J. Kahlbow, F. Guber, Yu. Kopylov, O. Teryaev, V. Wagner, I. Selyuzhenkov, A. Malakhov, O. Streltsova, A. Kolozhvari, V. Burtsev, P. Alekseev, M. Rumyantsev, H. Törnqvist, E. Zherebtsova, S. Sedykh, P. Rukoyatkin, I. Gabdrakhmanov, A. Bolozdynya, A. Kugler, M. Shitenkov, N. Barbashina, N. Zhigareva, A. Izvestnyy, Yu. Kovalev, S. Kuklin, K. Roslon, N. Tarasov, O. Rogachevsky, A. Galavanov, S. Merts, Thomas Aumann, B. Dabrowska, V. Palchik, L. Kovachev, E. Atkin, R. Nagdasev, A. Maksymchyuk, V. Golovatyuk, N. Sukhov, J. Chen, G. Laskaris, E. Zubarev, V. Slepnev, T. Aushev, A. Sorin, B. Löher, S. Sergeev, V. Panin, V. Karjavin, A. Sheremeteva, E. Kulish, V. Sosnovtsev, G. Pokatashkin, G. Johansson, S. Buzin, K. Filippov, E. Streletskaya, M. Peryt, I. Mardor, Yu.P. Petukhov, V. Tarasov, H. Scheit, M. Zuev, P. Batyuk, V. Balandin, A. Shchipunov, I. Yaron, E. Ladygin, Song Zhang, D. Dabrowski, R. Cruz-Torres, A. Beck, T. Starecki, N. Voytishin, I. Tyapkin, A. Kisiel, and S. Afanasiev
Subjects: Physics, Hydrogen, Isotope, Scattering, Nuclear Theory, General Physics and Astronomy, chemistry.chemical_element, nuclear structure, experiments with inverse kinematics, quasi-free scattering, short-range correlations, 01 natural sciences, 010305 fluids & plasmas, Ion, Nuclear physics, chemistry, 0103 physical sciences, Particle, Facility for Antiproton and Ion Research, 010306 general physics, Nucleon, Wave function, Nuclear Experiment
Abstract: Particle knockout scattering experiments1,2 are fundamental for mapping the structure of atomic nuclei2–6, but their interpretation is often complicated by initial- and final-state interactions of the incoming and scattered particles1,2,7–9. Such interactions lead to reduction in the scattered particle flux and distort their kinematics. Here we overcome this limitation by measuring the quasi-free scattering of 48 GeV c–1 12C ions from hydrogen. The distribution of single protons is studied by detecting two protons at large angles in coincidence with an intact 11B nucleus. The 11B detection suppresses the otherwise large distortions of reconstructed single-proton distributions induced by initial- and final-state interactions. By further detecting residual 10B and 10Be nuclei, we also identified short-range correlated nucleon–nucleon pairs9–13 and provide direct experimental evidence for separation of the pair wavefunction from that of the residual many-body nuclear system9,14. All measured reactions are well described by theoretical calculations that include no distortions from the initial- and final-state interactions. Our results showcase the ability to study the short-distance structure of short-lived radioactive nuclei at the forthcoming Facility for Antiproton and Ion Research (FAIR)15 and Facility for Rare Isotope Beams (FRIB)16 facilities, which is relevant for understanding the structure and properties of nuclei far from stability and the formation of visible matter in the Universe. Initial- and final-state interactions distort the kinematics in particle knockout scattering experiments, complicating their interpretation. These effects are suppressed by detecting 11B nuclei in quasi-free scattering of 12C ions from hydrogen.
Published: 2021

22. Probing the symmetry energy with the spectral pion ratio

Author: Naohiro Inabe, Y. Leifels, J. Estee, P. Morfouace, mrow, Piotr Pawłowski, W. G. Lynch, Kazuo Ieki, H. Scheit, Thomas Aumann, Nobuyuki Chiga, D. M. Rossi, Yasuhiro Togano, C.Y. Tsang, J. Łukasik, Byung-Sik Hong, H.S. Lee, Hiroyoshi Sakurai, G. Jhang, A. Snoch, K. Pelczar, Jongmin Lee, T. Isobe, mi> π, H. Toernqvist, C. Santamaria, Hidetada Baba, L. Atar, G. Cerizza, Takashi Nakamura, N. Fukuda, Y. M. Zhang, R. Wang, K. Boretzky, S. Nishimura, M. Kurata-Nishimura, mi> Rit, A. Horvat, M. B. Tsang, H. Sato, Noritsugu Nakatsuka, Alan McIntosh, Anna Sochocka, Toshiyuki Sumikama, J. J. Manfredi, Igor Gašparić, D. Suzuki, Yosuke Kondo, Y. Shimizu, Zhigang Xiao, Sherry Yennello, T. Kobayashi, S. Tangwancharoen, Hideaki Otsu, J. Barney, Rebecca Shane, T. Murakami, Hiroyuki Takeda, Herbert A. Simon, M.D. Cozma, J. Brzychczyk, M. Kaneko, D.S. Ahn, Y.J. Kim, H. Suzuki, and P. Lasko
Subjects: Physics, Equation of state, Proton, Isotope, Nuclear Theory, FOS: Physical sciences, General Physics and Astronomy, 01 natural sciences, Symmetry (physics), Spectral line, Neutron star, Pion, 0103 physical sciences, Physics::Accelerator Physics, Neutron, Nuclear Experiment (nucl-ex), Atomic physics, Nuclear Experiment, 010306 general physics
Abstract: Many neutron star (NS) properties, such as the proton fraction within a NS, reflect the symmetry energy contributions to the Equation of State that dominate when neutron and proton densities differ strongly. To constrain these contributions at supra-saturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be $42 < L < 117$ MeV. This value is slightly lower but consistent with the $L$ values deduced from a recent measurement of the neutron skin thickness of $^{208}$Pb.
Published: 2021

23. NeuLAND: The high-resolution neutron time-of-flight spectrometer for R3B at FAIR

Author: M.I. Cherciu, N.G. Kozlenko, Andreas Martin Heinz, P. Russotto, Christoph Langer, Z. Elekes, Nasser Kalantar-Nayestanaki, G. Ickert, Thomas Aumann, Thomas Nilsson, L. Zanetti, M. Volknandt, E. M. Orischin, Heiko Scheit, K. Koch, E.V. Pagano, V. Kuznetsov, S. Chakraborty, U. Datta, V. L. Golovtsov, N. Kurz, E. Hoemann, Tanja Heftrich, S. S. Volkov, J. Dreyer, M. Kempe, D. M. Rossi, T. Hensel, A. Horvat, C. Caesar, V. Wagner, G. Politi, I. Lihtar, F. Schindler, B. Löher, Ahibur Rahaman, Catherine Rigollet, J. Kahlbow, H. Törnqvist, A. Kelic-Heil, Herbert A. Simon, Daniel Stach, E. De Filippo, D. Galaviz, N. S. Martorana, Daniel Bemmerer, D. Gonzalez Diaz, D. Körper, Jorge Machado, E. Stan, B. Gnoffo, L. V. Chulkov, P. Teubig, N. Gruzinsky, J. Mayer, G. Alkhazov, J. Hehner, Rene Reifarth, S. Wranne, S. Pirrone, Håkan T Johansson, K. Miki, Lukas Bott, E. Geraci, K. Boretzky, I. Gašparić, H. Heggen, D. Kresan, M. Trimarchi, Kathrin Göbel, D. Jelavić Malenica, J. Stomvall Gill, S.V. Bondarev, M. Holl, Andreas Zilges, D. Yakorev, Joachim Enders, L. Atar, P.-M. Potlog, L. Uvarov, Björn Jonson, Andreas Wagner, Matthias Heil, M. Ciobanu, Á. Horváth, A.G. Krivshich, M. Röder, C.A. Douma, Y. Leifels, Deniz Savran, Kai Zuber, Research unit Nuclear & Hadron Physics, and Nuclear Energy
Subjects: Physics, Nuclear and High Energy Physics, Spectrometer, business.industry, High-energy neutron detection, Reactions with relativistic radioactive beams, Plastic scintillator array, Multi-neutron detection, Detector, Scintillator, Time of flight, Optics, Neutron detection, Facility for Antiproton and Ion Research, Neutron, ddc:530, Nuclear Experiment, business, Instrumentation, Image resolution
Abstract: Nuclear instruments & methods in physics research / A 1014, 165701 (2021). doi:10.1016/j.nima.2021.165701, Published by North-Holland Publ. Co., Amsterdam
Published: 2021
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24. Rapidity distributions of Z = 1 isotopes and the nuclear symmetry energy from Sn+Sn collisions with radioactive beams at 270 MeV/nucleon

Author: G. Cerizza, Byung-Sik Hong, Naohito Inabe, Piotr Pawłowski, P. Lasko, Toshiyuki Sumikama, T. Isobe, H. Sato, Noritsugu Nakatsuka, Akira Ono, T. Kobayashi, Yosuke Kondo, Alan McIntosh, P. Morfouace, D. M. Rossi, Jongmin Lee, N. Fukuda, Sherry Yennello, Kazuo Ieki, D.S. Ahn, J. Estee, H. Baba, J. Barney, Igor Gašparić, W. G. Lynch, D. Suzuki, J. Brzychczyk, Thomas Aumann, Hiroyuki Takeda, John Yurkon, A. Horvat, S. Nishimura, M. Kaneko, Hiroyoshi Sakurai, Y. M. Zhang, Yasuhiro Togano, S. Tangwancharoen, Zhigang Xiao, R. Olsen, M. Kurata-Nishimura, C.Y. Tsang, J. Łukasik, M. B. Tsang, K. Pelczar, Y. Leifels, Herbert A. Simon, N. Ikeno, J. J. Manfredi, Nobuyuki Chiga, R. Wang, C. Santamaria, H. Törnqvist, K. Boretzky, Hideaki Otsu, Rebecca Shane, G. Jhang, T. Ichihara, T. Murakami, Takashi Nakamura, H. Suzuki, H.S. Lee, Yohei Shimizu, Y.J. Kim, H. Scheit, and L. Atar
Subjects: Nuclear and High Energy Physics, Hydrogen, Proton, QC1-999, Nuclear Theory, chemistry.chemical_element, Nuclear physics, Antisymmetrized molecular dynamics, cluster productions, ddc:530, Rapidity, Neutron, Nuclear Experiment, Physics, Isotope, heavy radioactive isotope collisions, antisymmetrized molecular dynamics, Cluster productions, Heavy radioactive isotope collisions, Nuclear symmetry energy, Symmetry (physics), chemistry, Deuterium, nuclear symmetry energy, Nucleon
Abstract: Physics letters / B 822, 136681 (2021). doi:10.1016/j.physletb.2021.136681, Published by North-Holland Publ., Amsterdam
Published: 2021
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25. Signature of a possible $\alpha $-cluster state in $N=Z$ doubly-magic $^{56}$Ni

Author: L. Perrot, S. M. Lukyanov, U. Garg, L. Caceres, B. Bastin, A. Krasznahorkay, M. A. Najafi, J. F. Libin, S. Damoy, Marine Vandebrouck, Franck Delaunay, Catherine Rigollet, L. Suen, M. Caamaño, Julien Gibelin, K. Boretzky, J. Van de Walle, Nasser Kalantar-Nayestanaki, Hidetoshi Akimune, H. Bouzomita, G. Lhoutellier, C. Stodel, J. Pancin, Riccardo Raabe, S. Bagchi, O. Kamalou, H. Savajols, M.N. Harakeh, T. Roger, B. Fernández-Domínguez, Y. E. Penionzhkevich, M. Sénoville, N. L. Achouri, K. Mazurek, G. F. Grinyer, E. Khan, S. Sambi, J. C. Thomas, M. Fujiwara, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: Nuclear and High Energy Physics, Hadron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Physics, Particles & Fields, 0103 physical sciences, medicine, Incident energy, Nuclear fusion, ddc:530, Multiplicity (chemistry), Nuclear Experiment, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Physics, Science & Technology, 010308 nuclear & particles physics, Cluster state, Physics, Nuclear, medicine.anatomical_structure, Physical Sciences, Atomic physics, α particles, Nucleus, Excitation
Abstract: An inelastic $\alpha$-scattering experiment on the unstable $N=Z$, doubly-magic $^{56}$Ni nucleus was performed in inverse kinematics at an incident energy of 50 A.MeV at GANIL. High multiplicity for $\alpha$-particle emission was observed within the limited phase-space of the experimental setup. This observation cannot be explained by means of the statistical-decay model. The ideal classical gas model at $kT$ = 0.4 MeV reproduces fairly well the experimental momentum distribution and the observed multiplicity of $\alpha$ particles corresponds to an excitation energy around 96 MeV. The method of distributed $m\alpha$-decay ensembles is in agreement with the experimental results if we assume that the $\alpha$-gas state in $^{56}$Ni exists at around $113^{+15}_{-17}$ MeV. These results suggest that there may exist an exotic state consisting of many $\alpha$ particles at the excitation energy of $113^{+15}_{-17}$ MeV., Comment: Accepted for publication in the European Physical Journal A
Published: 2020
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26. Excitation of Baryonic Resonances in Isobaric Charge-Exchange Reactions of Medium-Mass Nuclei

Author: S. Pietri, Helmut Weick, Enrique Casarejos, H. Lenske, J. L. Rodriguez-Sanchez, A. Kelic-Heil, J. Vargas, D. Cortina-Gil, M. Caamaño, K. Itahashi, M. Takechi, Yu. A. Litvinov, J. Atkinson, Alfredo Estrade, K. Boretzky, E. Haettner, T. Saito, H. Alvarez-Pol, Thomas Aumann, C. Paradela, Hans Geissel, Isaac Vidaña, J. Benlliure, S. Beceiro-Novo, Yassid Ayyad, A. Prochazka, C. Scheidenberger, D. Pérez-Loureiro, Yukichi Tanaka, J. S. Winfield, and P. Díaz Fernández
Subjects: Physics, Baryon, Isobaric process, Atomic physics, Excitation, Charge exchange
Published: 2020
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27. Extending the Southern Shore of the Island of Inversion to F28

Author: J. Mayer, Noritsugu Nakatsuka, Michael Thoennessen, A. Gillibert, Ákos Horváth, Q. Deshayes, Yosuke Kondo, J. Tscheuschner, Nasser Kalantar-Nayestanaki, J. M. Gheller, István Kuti, M. Shikata, Thomas Aumann, C. Caesar, J. Tsubota, A. Revel, N. L. Achouri, W. He, Z. Elekes, Calem Hoffman, Shoichiro Kawase, Heiko Scheit, J. Kahlbow, Masahiro Yasuda, H. Simon, H. Sato, K. Yoneda, A. Horvat, K. Nakano, Igor Gašparić, T. Ozaki, H. Chae, J. A. Tostevin, L. Stuhl, K. Miki, F. de Oliveira Santos, H. L. Crawford, D. Calvet, Stefanos Paschalis, S. Masuoka, T. Isobe, A. Obertelli, Tomoki Saito, Momoko Tanaka, N. A. Orr, Shoko Koyama, Nobuyuki Chiga, L. Atar, Y. Satou, P. Fallon, Atsumi Saito, Zsolt Dombrádi, H. Törnqvist, Jongwon Hwang, A. Corsi, Julien Gibelin, K. Boretzky, A. Delbart, D. M. Rossi, H. Baba, Masaki Sasano, D. Sohler, V. Lapoux, M. A. Najafi, S. K. Kim, A. Hirayama, H. Al Falou, K. Kisamori, T. Tomai, V. Panin, P. Schrock, Takashi Nakamura, Yasuhiro Togano, M.N. Harakeh, M. Holl, Zaihong Yang, F. Nowacki, T. Kobayashi, Cenxi Yuan, D. Körper, Tomohiro Uesaka, Thomas Nilsson, C. A. Douma, Simon Lindberg, Hideaki Otsu, O. Sorlin, T. Murakami, Yohei Shimizu, Fabia Schindler, Franck Delaunay, F. M. Marqués, and Satoshi Takeuchi
Subjects: Physics, Proton, Island of inversion, General Physics and Astronomy, 01 natural sciences, Spectral line, Momentum, 0103 physical sciences, Neutron, Atomic physics, 010306 general physics, Nucleon, Spectroscopy, Ground state
Abstract: Detailed spectroscopy of the neutron-unbound nucleus 28 F has been performed for the first time following proton/neutron removal from 29 Ne / 29 F beams at energies around 230 MeV / nucleon . The invariant-mass spectra were reconstructed for both the 27 F ( * ) + n and 26 F ( * ) + 2 n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the 28 F ground state, with S n ( 28 F ) = − 199 ( 6 ) keV , while analysis of the 2 n decay channel allowed a considerably improved S n ( 27 F ) = 1620 ( 60 ) keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of 28 F . Importantly, in the case of the ground state, the reconstructed 27 F + n momentum distribution following neutron removal from 29 F indicates that it arises mainly from the 1 p 3 / 2 neutron intruder configuration. This demonstrates that the island of inversion around N = 20 includes 28 F , and most probably 29 F , and suggests that 28 O is not doubly magic.
Published: 2020
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28. Fragmentation of Single-Particle Strength around the Doubly Magic Nucleus Sn132 and the Position of the 0f5/2 Proton-Hole State in In131

Author: Hiroyoshi Sakurai, J. Tscheuschner, Yosuke Kondo, A. Bracco, D. Semmler, S. Nishimura, T. Motobayashi, Ryo Taniuchi, N. Imai, Kazuo Ieki, A. Jungclaus, Ismael Martel, F. Camera, P. Schrock, Heiko Scheit, Juzo Zenihiro, Andreas Zilges, V. Derya, D. S. Ahn, K. Boretzky, Yasuhiro Togano, R. Avigo, M.N. Harakeh, D. Symochko, Hiroyuki Takeda, T. Kubo, Shoko Koyama, D. M. Rossi, M. Shikata, H. Baba, Agnese Giaz, Haik Simon, T. Ozaki, J. L. Rodriguez-Sanchez, P. Doornenbal, David Steppenbeck, Atsumi Saito, I. Syndikus, C. Caesar, M. Heil, Si-Ge Chen, J. A. Tostevin, J. Tsubota, Nagao Kobayashi, Deniz Savran, Yoshiaki Shiga, U. Garg, Marina Petri, N. Nakatsuka, Masafumi Matsushita, Toshiyuki Sumikama, Naohito Inabe, Victor Vaquero, Takashi Nakamura, B. Million, J. Endres, Satoshi Takeuchi, A. Horvat, Y. Shimizu, E. V. Litvinova, K. Yoneda, H. Suzuki, O. Wieland, Rene Reifarth, Hideaki Otsu, H. Wang, Fabia Schindler, Shuichi Ota, Nasser Kalantar-Nayestanaki, M. Nishimura, Thomas Aumann, and N. Fukuda
Subjects: Physics, medicine.anatomical_structure, Fragmentation (mass spectrometry), Astrophysics::High Energy Astrophysical Phenomena, Excited state, 0103 physical sciences, Magic (programming), medicine, General Physics and Astronomy, Atomic physics, 010306 general physics, 01 natural sciences, Nucleus
Abstract: Spectroscopic factors of neutron-hole and proton-hole states in 131Sn and 131In, respectively, were measured using one-nucleon removal reactions from doubly magic 132Sn at relativistic energies. For 131In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5=2− state at 3275(50) keV to the known 1=2− level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of singlehole strength in 131Sn and 131In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling
Published: 2020
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29. Lifetime measurement of the $^{26}0 g.s.$ at SAMURAI

Author: Hiroyuki Takeda, Takashi Nakamura, Hideaki Otsu, Olivier Sorlin, Masaki Sasano, Zaihong Yang, I. Murray, D. M. Rossi, Yuya Kubota, A. Hirayama, Thomas Aumann, Makoto Yasuda, K. I. Hahn, L. Atar, H. Baba, Sonja Storck, S. Choi, Z. Halász, Yohei Shimizu, C. Caesar, L. Stuhl, H. Scheit, C. Lehr, Nobuyuki Chiga, Yasuhiro Togano, Thomas Nilsson, Hans Törnqvist, Z. Elekes, D. Körper, M. Matsumoto, M. L. Cortés, Naohito Inabe, Yosuke Kondo, T. Murakami, D. S. Ahn, K. Yoneda, Marina Petri, Atsumi Saito, T. Tomai, Tomohiro Uesaka, M. Parlog, Simon Lindberg, V. Panin, M. Marques, D. Cortina-Gil, T. Isobe, H. Chae, S. K. Kim, István Kuti, Jongwon Hwang, Herbert A. Simon, P. Schrock, Naoki Fukuda, T. Kobayashi, J. Kahlbow, H. Suzuki, D. Sohler, H. Yamada, I. Syndikus, K. Boretzky, Q. Deshayes, P. Doornenbal, I. Gaparic, Stefanos Paschalis, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), SAMURAI20, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Physics, Superconductivity, History, Radionuclide, Spectrum analyzer, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 010305 fluids & plasmas, Computer Science Applications, Education, Nuclear physics, Stack (abstract data type), 0103 physical sciences, Physics::Accelerator Physics, ddc:530, Neutron, Radio isotopes, 010306 general physics, Ground state, Nuclear Experiment, Beam (structure)
Abstract: 27th International Nuclear Physics Conference, INPC2019, Glasgow, United Kingdom, 29 Jul 2019 - 2 Aug 2019; Journal of physics / Conference series 1643(1), 012106 (2020). doi:10.1088/1742-6596/1643/1/012106, Published by IOP Publ., Bristol
Published: 2020
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30. Probing the Z = 6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions

Author: A. Henriques, J. S. Winfield, Thomas Nilsson, Rene Reifarth, M. Heine, E. Cravo, L. M. Fraile, Håkan T Johansson, O. Sorlin, L. Chulkov, W. N. Catford, A. Revel, J. Marganiec-Gałązka, Pavel Golubev, H. Scheit, S. Beceiro-Novo, Joakim Cederkäll, R. Gernhäuser, Carlos A. Bertulani, Y. Togano, T. Le Bleis, D. Cortina-Gil, L. Atar, G. L. Wilson, S. Pietri, F. Farinon, Kai Zuber, N. Kurz, Andreas Zilges, V. Volkov, M. Heil, C. Langer, A. Kelic-Heil, R. Plag, Catherine Rigollet, J. Enders, Iris Dillmann, U. Datta Pramanik, Jorge Machado, H. Alvarez-Pol, I. Syndikus, A. O. Macchiavelli, Marina Petri, D. Yakorev, M. Holl, Enrique Casarejos, G. Ribeiro, Mikhail V. Zhukov, Stefanos Paschalis, María José García Borge, Marine Vandebrouck, Deniz Savran, V. Panin, Björn Jonson, Nasser Kalantar-Nayestanaki, Philip Woods, Ángel Perea, C. Wheldon, R. Crespo, Thomas Aumann, Hans Geissel, Z. Elekes, Andreas Martin Heinz, J. M. Boillos, B. A. Brown, D. Galaviz, T. Kröll, S. Chakraborty, K. Göbel, Enrique Nácher, H. Weick, Rituparna Kanungo, P. Díaz Fernández, K. Boretzky, M. Caamaño, Anisur Rahaman, C. Caesar, J. Benlliure, F. Wamers, D. Rossi, Haik Simon, Olof Tengblad, C. Nociforo, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), R$^3$B, Energy and Sustainability Research Institute Groni, Research unit Nuclear & Hadron Physics, Royal Society (UK), Department of Energy (US), Federal Ministry of Education and Research (Germany), State of Hesse, Technische Universität Darmstadt, Helmholtz Association, European Young Investigator Awards, Swedish Research Council, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Xunta de Galicia, German Research Foundation, National Science Foundation (US), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Nuclear and High Energy Physics, Quasi-free scattering reactions, Field (physics), Proton, Nuclear Theory, Shell (structure), FOS: Physical sciences, Shell evolution, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Atomic, Nuclear physics, Magic number (programming), Particle and Plasma Physics, 0103 physical sciences, Neutron, Nuclear, ddc:530, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Mathematical Physics, Spin-½, Physics, 010308 nuclear & particles physics, Scattering, Molecular, Spin-orbit splitting, Nuclear & Particles Physics, lcsh:QC1-999, 3. Good health, Valley of stability, Tensor force, Magic numbers, Física nuclear, lcsh:Physics, Astronomical and Space Sciences, Exotic nuclei
Abstract: 9 pags., 5 figs., 2 tabs., The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 2 state of C. The experimental findings support the notion of a moderate reduction of the proton 1p−1p spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline., This work was supported by the Royal Society award UF150476, UK STFC awards ST/M006433/1 and ST/P003885/1, U.S. Department of Energy, Office of Nuclear Physics, contract No. DE-AC02- 05CH11231 (LBNL), the German Federal Ministry of Education and Research (BMBF projects 05P15RDFN1, 05P15WOFNA and 05P19RDFN1), the GSI-TU Darmstadt cooperation agreement, the State of Hesse through the LOEWE center HIC for FAIR, the Helmholtz-Gemeinschaft through the graduate school HGS-HIRe and Young Investigators Grants, and the Swedish Research Council under contract number 621-2011-5324. This work was also supported by the Spanish research grants (Ministerio Ciencia e Innovación), FPA2015-64969-P, FPA2015-69640-C2-1-P, FPA2017- 87568-P, PGC2018-099746-B-C21, RTI2018-098868-B-I00, Undidad de Excelencia María de Maeztu under project MDM-2016.0692, and the Xunta de Galicia research grant GRC ED431C 2017/54. This work was partly supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project-ID 279384907 - SFB 1245. C.A.B. acknowledges support from the U.S. NSF Grant No. 1415656, and U.S. DOE Grant No. DE-FG02-08ER41533.
Published: 2020
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31. Isobaric charge-exchange reactions: a tool to study the excitation of baryonic resonances in exotic nuclear matter

Author: Enrique Casarejos, M. Caamaño, A. Kelic-Heil, S. Pietri, A. Prochazka, Thomas Aumann, T. Saito, A. Estrade, Isaac Vidaña, Emma Haettner, S. Beceiro-Novo, Horst Lenske, Yassid Ayyad, D. Pérez-Loureiro, J. Vargas, D. Cortina-Gil, Hans Geissel, H. Alvarez-Pol, J. S. Winfield, C. Scheidenberger, Helmut Weick, Y.K. Tanaka, J. Atkinson, M. Takechi, J. Benlliure, K. Boretzky, C. Paradela, J. L. Rodriguez-Sanchez, K. Itahashi, Yu. A. Litvinov, and P. Díaz Fernández
Subjects: Physics, History, Nuclear Theory, Resonance, Nuclear matter, Spectral line, Computer Science Applications, Education, Baryon, Nuclear physics, Excited state, Isobaric process, Neutron, ddc:530, Nuclear Experiment, Excitation
Abstract: 27th International Nuclear Physics Conference, INPC2019, Glasgow, United Kingdom, 29 Jul 2019 - 2 Aug 2019; Journal of physics / Conference Series 1643, 012104 (2020). doi:10.1088/1742-6596/1643/1/012104, Published by IOP Publ., Bristol
Published: 2020
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32. Excitation of baryonic resonances in stable medium-mass nuclei of Sn

Author: S. Pietri, E. Haettner, Y. Ayyad, P. Díaz Fernández, A. Prochazka, Yu. A. Litvinov, Yukichi Tanaka, Alfredo Estrade, C. Scheidenberger, C. Paradela, J. S. Winfield, H. Lenske, H. Alvarez-Pol, S. Beceiro-Novo, A. Kelic-Heil, K. Itahashi, D. Pérez-Loureiro, Thomas Aumann, K. Boretzky, Hans Geissel, J. L. Rodriguez-Sanchez, Helmut Weick, E. Casarejos, J. Atkinson, Isaac Vidaña, M. Takechi, M. Caamaño, J. Benlliure, J. Vargas, D. Cortina-Gil, and T. Saito
Subjects: Physics, History, Spectrometer, Resonance, Spectral line, Computer Science Applications, Education, Baryon, Excited state, Isobaric process, ddc:530, Neutron, Atomic physics, Excitation
Abstract: Journal of physics / Conference series 1667, 012036 (2020). doi:10.1088/1742-6596/1667/1/012036, Published by IOP Publ., Bristol
Published: 2020
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33. Experimental study of 4 n with 8He(p,2p) reaction

Author: M. Böhmer, Masaki Sasano, S. Reichert, Naohito Inabe, S. Chen, T. Shimada, M. Matsumoto, Susumu Shimoura, I. Stefan, J. Kahlbow, N. Kalantar-Nayestanaki, T. Harada, D. Symochko, István Kuti, S. W. Huang, D. Cortina, Tomohiro Uesaka, Z. Ge, N. L. Achouri, Yosuke Kondo, Hiroyuki Takeda, K. Yoneda, B. Fernández-Domínguez, U. Forsberg, Z. Elekes, Roman Gernhäuser, Y. Yasuda, H. Suzuki, Yohei Shimizu, D. Beaumel, D. Kim, C. A. Douma, Yukie Maeda, A. Hirayama, J. M. Gheller, Heiko Scheit, F. Dufter, T. Elidiano, Yasuhiro Togano, M. L. Cortés, M. Potlog, Nobuyuki Chiga, P. J. Li, Juzo Zenihiro, B. Yang, T. Isobe, M. Caamaño, Thomas Aumann, H. T. Törnqvsit, A. Gillibert, D. S. Ahn, F. Schindler, M.N. Harakeh, J. Feng, J. Tscheuschner, S. Kim, Atsumi Saito, L. Zanetti, P. Koseoglou, V. Wagner, M. Parlog, B. M. Godoy, N. Orr, Takashi Nakamura, Yu-xin Liu, J. Mayer, A. Obertelli, Yuya Kubota, Hideaki Otsu, S. Storck, S. Masuoka, K. Boretzky, Kathrin Wimmer, H. Miki, T. Tomai, F. M. Marqués, V. Panin, P. Doornenbal, Stefanos Paschalis, L. Yang, Satoshi Takeuchi, M. A. Knösel, Igor Gašparić, T. Kobayashi, C. Lehr, H. Yang, C. Lenain, M. Miwa, Z. Halász, A. Revel, H. Sato, T. Fujino, D. M. Rossi, H. Baba, S. Park, I. Murray, L. Stuhl, H. Yamada, J. Gibelin, J. Tanaka, Naoki Fukuda, RIKEN Nishina Center for Accelerator-Based Science, German Research Foundation, Federal Ministry of Education and Research (Germany), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Physics, Paper, History, 010308 nuclear & particles physics, tetraneutron, nuclear force, proton knock-out, radioactive beams, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Computer Science Applications, Education, ddc, Nuclear physics, 0103 physical sciences, Tetraneutron, Neutron, ddc:530, 010306 general physics
Abstract: 7 pags., 3 figs. -- 27th International Nuclear Physics Conference (INPC2019), The tetraneutron has attracted the attention of nuclear physicists during the past decades, but there is still no unambiguous confirmation of its existence or nonexistence. A new experiment based on 8 He(p,2p)7H{t+4n} reaction, with direct detection of the four neutrons, has been carried out at RIBF, which can hopefully help to draw a definite conclusion on the tetraneutron system., We acknowledge the support of the RIBF accelerator staff and the BigRIPS team for providing the high-quality beam. Z. H. Yang acknowledges the financial support from the Foreign Postdoctoral Researcher program of RIKEN. T. Aumann acknowledges the support by DFG via SFB 1245. P. Koseoglou acknowledges the support from BMBF (NUSTAR.DA grant No.05P 15RDFN1).
Published: 2020
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34. Fragmentation of Single-Particle Strength around the Doubly Magic Nucleus ^{132}Sn and the Position of the 0f_{5/2} Proton-Hole State in ^{131}In

Author: V, Vaquero, A, Jungclaus, T, Aumann, J, Tscheuschner, E V, Litvinova, J A, Tostevin, H, Baba, D S, Ahn, R, Avigo, K, Boretzky, A, Bracco, C, Caesar, F, Camera, S, Chen, V, Derya, P, Doornenbal, J, Endres, N, Fukuda, U, Garg, A, Giaz, M N, Harakeh, M, Heil, A, Horvat, K, Ieki, N, Imai, N, Inabe, N, Kalantar-Nayestanaki, N, Kobayashi, Y, Kondo, S, Koyama, T, Kubo, I, Martel, M, Matsushita, B, Million, T, Motobayashi, T, Nakamura, N, Nakatsuka, M, Nishimura, S, Nishimura, S, Ota, H, Otsu, T, Ozaki, M, Petri, R, Reifarth, J L, Rodríguez-Sánchez, D, Rossi, A T, Saito, H, Sakurai, D, Savran, H, Scheit, F, Schindler, P, Schrock, D, Semmler, Y, Shiga, M, Shikata, Y, Shimizu, H, Simon, D, Steppenbeck, H, Suzuki, T, Sumikama, D, Symochko, I, Syndikus, H, Takeda, S, Takeuchi, R, Taniuchi, Y, Togano, J, Tsubota, H, Wang, O, Wieland, K, Yoneda, J, Zenihiro, and A, Zilges
Abstract: Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.
Published: 2019

35. Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range

Author: P. J. Woods, Matthias Heil, K. Boretzky, W. N. Catford, A. Henriques, M. Caamaño, Thomas Nilsson, J. Benlliure, P. Velho, Yasuhiro Togano, F. Wamers, I. Syndikus, E. Cravo, H. Alvarez-Pol, Joachim Enders, N. Kurz, O. Sorlin, Rituparna Kanungo, Deniz Savran, C. Nociforo, Mikhail V. Zhukov, L. M. Fraile, Marine Vandebrouck, Björn Jonson, M. Heine, Haik Simon, Roman Gernhäuser, Olof Tengblad, M. Holl, Z. Elekes, M. A. Najafi, Heiko Scheit, Carlos A. Bertulani, Kai Zuber, J. S. Winfield, T. Le Bleis, D. Cortina-Gil, L. Atar, Enrique Casarejos, Joakim Cederkäll, T. Kröll, C. Caesar, G. L. Wilson, G. Ribeiro, A. Kelic-Heil, Christoph Langer, Nasser Kalantar-Nayestanaki, Helmut Weick, Håkan T Johansson, Pavel Golubev, C. Wheldon, Thomas Aumann, Andreas Martin Heinz, Stefanos Paschalis, P. Díaz Fernández, D. M. Rossi, Enrique Nácher, Simon Lindberg, Catherine Rigollet, S. Beceiro-Novo, J. M. Boillos, L. V. Chulkov, Tanja Heftrich, V. Panin, D. Galaviz Redondo, Jorge Machado, Marina Petri, Rene Reifarth, Iris Dillmann, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), R3B, Federal Ministry of Education and Research (Germany), Technische Universität Darmstadt, Helmholtz International Center for FAIR, European Commission, Ministerio de Ciencia e Innovación (España), Ministerio de Economía, Industria y Competitividad (España), Swedish Research Council, National Science Foundation (US), Department of Energy (US), Fundação para a Ciência e a Tecnologia (Portugal), LIBPhys-UNL, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear and High Energy Physics, Proton, 3313 Tecnología E Ingeniería Mecánicas, media_common.quotation_subject, Nuclear Theory, Aucun, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Asymmetry, Nuclear physics, Momentum, Shell model, 0103 physical sciences, Neutron, ddc:530, 010306 general physics, Nuclear Experiment, Quasi-free scattering, media_common, Physics, Range (particle radiation), 010308 nuclear & particles physics, Scattering, 2207 Física Atómica y Nuclear, lcsh:QC1-999, Inverse kinematics, Isospin, Física nuclear, Spectroscopic factors, Beam (structure), lcsh:Physics
Abstract: 7 pags., 4 figs., 2 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0, The quasi-free scattering reactions C(p,2p) and C(p,pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the RB-LAND setup. The outgoing proton-proton and proton-neutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the C(p,2p) and C(p,pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of single-particle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p,2p) are found to be 'significantly smaller than for (p,pn) reactions for all investigated nuclei., This work was supported by the German Federal Ministry of Education and Research (BMBF projects 05P2015RDFN1 and 05P15WOFNA), through the GSI-TU Darmstadt cooperation agreement, by the State of Hesse through the LOEWE center HIC for FAIR, and the Helmholtz-Gemeinschaft through the graduate school HGS-HIRe. This work was supported by the European Union by means of the European Commission within its Seventh Framework Program (FP7) via ENSAR (Contract No. 262010), and the Spanish CICYT research grants FPA2012-32443, FPA2015-64969-07387, and FPA2015-69640-C2-1-P. This work has supported by the Swedish Research Council under contract number 621-2011-5324. C.A.B. acknowledges support from the U.S. NSF grant No. 1415656 and the U.S. DOE grant No. DE-FG02-08ER41533. Supported by the Portuguese FCT under the project PTDC/FIS/ 103902/2008.
Published: 2019
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36. Exclusive measurements of quasi-free proton scattering reactions in inverse and complete kinematics

Author: Heiko Scheit, Matthias Heil, T. Le Bleis, D. Cortina-Gil, Roman Gernhäuser, Christoph Langer, Roy Crawford Lemmon, C. Wimmer, Ralf Plag, K. Boretzky, O. Ershova, A. Kelic-Heil, Carlos A. Bertulani, Thomas Nilsson, C. Caesar, Björn Jonson, Marielle Chartier, F. Wamers, Hans Geissel, Rene Reifarth, V. Panin, H. Alvarez-Pol, J. Taylor, Herbert A. Simon, Thomas Aumann, L. V. Chulkov, Stefanos Paschalis, D. M. Rossi, Y. Aksyutina, Helmut Weick, Håkan T Johansson, Marina Petri, Joachim Enders, and Universidade de Santiago de Compostela. Departamento de Física de Partículas
Subjects: Nuclear and High Energy Physics, Proton, Nuclear Theory, Inverse, 01 natural sciences, 0103 physical sciences, Single-particle states, ddc:530, 010306 general physics, Spectroscopy, Nuclear Experiment, Quasi-free scattering, Physics, Inverse kinematics, 010308 nuclear & particles physics, Scattering, lcsh:QC1-999, Excited state, Atomic physics, Spectroscopic factors, Nucleon, Ground state, lcsh:Physics
Abstract: Physics letters / B 753, 204 - 210(2016). doi:10.1016/j.physletb.2015.11.082, Published by North-Holland Publ., Amsterdam
Published: 2016
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37. Observation of isoscalar multipole strengths in exotic doubly-magic 56Ni in inelastic α scattering in inverse kinematics

Author: N.L. Achouri, Marine Vandebrouck, S. Damoy, Elias Khan, H. Bouzomita, M. Fujiwara, K. Mazurek, L. Caceres, J. F. Libin, J. Van de Walle, M. Caamaño, U. Garg, S. M. Lukyanov, H. Savajols, A. Krasznahorkay, J. Pancin, K. Boretzky, B. Bastin, S. Bagchi, G. F. Grinyer, G. Lhoutellier, C. Stodel, Riccardo Raabe, L. Suen, J. Gibelin, Nasser Kalantar-Nayestanaki, Catherine Rigollet, Hidetoshi Akimune, S. Sambi, J. C. Thomas, O. Kamalou, L. Perrot, M. A. Najafi, T. Roger, M. Senoville, F. Delaunay, B. Fernández-Domínguez, Y. E. Penionzhkevich, M.N. Harakeh, Universidade de Santiago de Compostela. Departamento de Física de Partículas, KVI-CART, University of Groningen, University of Groningen [Groningen], Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidade de Santiago de Compostela [Spain] (USC ), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institute for Nuclear Research [Budapest] (ATOMKI), Hungarian Academy of Sciences (MTA), Flerov Laboratory of Nuclear Reactions [Dubna] (FLNR), Joint Institute for Nuclear Research (JINR), Instituut voor Kern-en Stralingsfysica (IKS), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), GANILEXP, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Research unit Nuclear & Hadron Physics
Subjects: Nuclear and High Energy Physics, Isoscalar, ACTIVE TARGET, Nuclear Theory, Magnetic monopole, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Resonance (particle physics), NUCLEAR INCOMPRESSIBILITY, Nuclear physics, ENERGY, ddc:530, Nuclear Experiment, Physics, Inverse kinematics, Isotope, Scattering, BEAMS, lcsh:QC1-999, 3. Good health, Dipole, ISOTOPES, DIPOLE RESONANCE, Atomic physics, Multipole expansion, MATTER, lcsh:Physics
Abstract: The Isoscalar Giant Monopole Resonance (ISGMR) and the Isoscalar Giant Dipole Resonance (ISGDR) compression modes have been studied in the doubly-magic unstable nucleus 56Ni. They were measured by inelastic α-particle scattering in inverse kinematics at 50MeV/u with the MAYA active target at the GANIL facility. The centroid of the ISGMR has been obtained at Ex=19.1 ±0.5MeV. Evidence for the low-lying part of the ISGDR has been found at Ex=17.4 ±0.7MeV. The strength distribution for the dipole mode shows similarity with the prediction from the Hartree–Fock (HF) based random-phase approximation (RPA)[1]. These measurements confirm inelastic α-particle scattering as a suitable probe for exciting the ISGMR and the ISGDR modes in radioactive isotopes in inverse kinematics This work was supported by the European Commission within the Seventh Framework Programme through IA-ENSAR (contract No. RII3-CT-2010-262010) and GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany, and the United States National Science Foundation (Grants Number PHY-1068192 and PHY-1419765) SI
Published: 2015
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38. Structure of Be13 studied in proton knockout from B14

Author: Roy Crawford Lemmon, C. Wimmer, U. Datta Pramanik, K. Goebel, I. Syndikus, Nasser Kalantar-Nayestanaki, C. Wheldon, Enrique Nácher, Thomas Aumann, J. S. Winfield, Andreas Martin Heinz, N. Kurz, L. M. Fraile, Hans Geissel, Rene Reifarth, Mikhail V. Zhukov, J. Marganiec, E. Cravo, P. Velho, M. Heine, M. Caamaño, M. Roeder, O. Ershova, Alfredo Estrade, Martin Freer, Daniel Bemmerer, G. L. Wilson, P. J. Woods, S. Pietri, Z. Elekes, G. Ribeiro, Björn Jonson, J. M. Boillos, Joakim Cederkäll, J. Taylor, J. Hagdahl, Herbert A. Simon, Paloma Diaz Fernandez, T. Kroell, Andreas Wagner, Matthias Heil, R. Crespo, A. Ignatov, M. J. G. Borge, K. Riisager, Roman Gernhaeuser, K. Boretzky, A. Movsesyan, Andreas Zilges, Carlos A. Bertulani, A. Hufnagel, H. O. U. Fynbo, A. Kelic-Heil, V. Panin, T. Le Bleis, Christoph Langer, D. Cortina-Gil, L. Atar, E. Casarejos, R. Thies, Jorge Machado, Joachim Enders, Olof Tengblad, Marina Petri, Ralf Plag, J. Benlliure, Deniz Savran, D. M. Rossi, Marielle Chartier, C. Caesar, Y. Aksyutina, Simon Lindberg, Catherine Rigollet, L. V. Chulkov, Daniel Galaviz, M. Holl, O. Sorlin, C. Nociforo, Helmut Weick, Håkan T Johansson, H. Scheit, W. N. Catford, Ángel Perea, Vladimir Avdeichikov, I. Dillmann, Pavel Golubev, F. Farinon, Stefanos Paschalis, H. Alvarez-Pol, R. Kanungo, Marine Vandebrouck, Kai Zuber, M. Labiche, A. Henriques, S. Beceiro-Novo, Thomas Nilsson, F. Wamers, and Tanja Heftrich
Subjects: Physics, Nuclear reaction, Proton, 010308 nuclear & particles physics, Nuclear Theory, Gamma ray, Halo nucleus, 01 natural sciences, Resonance (particle physics), Nuclear physics, Excited state, 0103 physical sciences, Neutron, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The neutron-unbound isotope Be-13 has been studied in several experiments using different reactions, different projectile energies, and different experimental setups. There is, however, no real consensus in the interpretation of the data, in particular concerning the structure of the low-lying excited states. Gathering new experimental information, which may reveal the Be-13 structure, is a challenge, particularly in light of its bridging role between Be-12, where the N = 8 neutron shell breaks down, and the Borromean halo nucleus Be-14. The purpose of the present study is to investigate the role of bound excited states in the reaction product Be-12 after proton knockout from B-14, by measuring coincidences between Be-12, neutrons, and gamma rays originating from de-excitation of states fed by neutron decay of Be-13. The Be-13 isotopes were produced in proton knockout from a 400 MeV/nucleon B-14 beam impinging on a CH2 target. The Be-12-n relative-energy spectrum d sigma/dE(fn) was obtained from coincidences between Be-12(g.s.) and a neutron, and also as threefold coincidences by adding gamma rays, from the de-excitation of excited states in Be-12. Neutron decay from the first 5/2(+) state in Be-13 to the 2(+) state in Be-12 at 2.11 MeV is confirmed. An energy independence of the proton-knockout mechanism is found from a comparison with data taken with a 35 MeV/nucleon B-14 beam. A low-lying p-wave resonance in Be-13(1/2(-)) is confirmed by comparing proton- and neutron-knockout data from B-14 and Be-14.
Published: 2018
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39. Study of multi-neutron systems with SAMURAI spectrometer

Author: K. Yoneda, Z. Elekes, Masaki Sasano, Heiko Scheit, Atsumi Saito, N. Inabe, I. Stefan, J. Tscheuschner, Mohsen Harakeh, Julien Gibelin, M. A. Knösel, K. Boretzky, Z. Ge, Takashi Nakamura, D. Kim, H. Sato, J. Kahlbow, Igor Gašparić, Y. Yasuda, Susumu Shimoura, T. Isobe, Juzo Zenihiro, M. Caamaño, Yosuke Kondo, S. Masuoka, H. Suzuki, A. Hirayama, S. W. Huang, C. A. Douma, B. M. Godoy, Z. Halász, H. Yamada, C. Lehr, M. Böhmer, Nobuyuki Chiga, A. Revel, N. L. Achouri, P. Koseoglou, Kathrin Wimmer, V. Wagner, N. A. Orr, M. Potlog, M. Miwa, B. Yang, A. Obertelli, T. Harada, H. T. Törnqvsit, S. Reichert, H. Miki, D. S. Ahn, T. Tomai, István Kuti, J. Mayer, J. Tanaka, S. Park, Yasuhiro Togano, M. Parlog, Naoki Fukuda, Yu-xin Liu, S. Chen, V. Panin, L. Zanetti, F. Schindler, S. Storck, T. Shimada, Tomohiro Uesaka, J. Feng, M. Matsumoto, Zaihong Yang, U. Forsberg, Roman Gernhäuser, I. Murray, F. Dufter, D. Symochko, L. Stuhl, J. M. Gheller, Hideaki Otsu, D. Beaumel, T. Kobayashi, H. Takeda, A. Gillibert, D. Cortina, P. Doornenbal, L. Yang, Nasser Kalantar-Nayestanaki, Satoshi Takeuchi, Thomas Aumann, Stefanos Paschalis, T. Fujino, D. M. Rossi, H. Baba, Yohei Shimizu, M. L. Cortés, F. M. Marqués, B. Fernández-Domínguez, Yuya Kubota, Yukie Maeda, S. K. Kim, P. J. Li, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Physics, Firm conclusion, Spectrometer, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 010305 fluids & plasmas, Nuclear physics, 0103 physical sciences, Tetraneutron, Neutron, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment
Abstract: The tetraneutron has been drawing the attention of the nuclear physics community for decades, but a firm conclusion on its existence and properties is still far from being reached despite many experimental and theoretical efforts. New measurements have recently been performed at RIBF with the SAMURAI spectrometer by applying complementary reaction probes, which will help to pin down the properties of this four-neutron system., Comment: 5 pages, 2 figures, conference proceedings of XXII International Conference on Few-Body Problems in Physics (FB22), Caen, France, July 2018
Published: 2018
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40. Strong neutron pairing in core+4n nuclei

Author: S. Beceiro-Novo, R. Thies, Jorge Machado, Andreas Martin Heinz, Tanja Heftrich, L. M. Fraile, A. Estrade, Marina Petri, T. Le Bleis, D. Cortina-Gil, L. Atar, T. Kröll, A. Knyazev, M. A. Najafi, G. L. Wilson, D. Rossi, Kai Zuber, A. Movsesyan, Z. Elekes, Simon Lindberg, I. Syndikus, P. Díaz Fernández, K. Göbel, Catherine Rigollet, Ángel Perea, R. Crespo, F. Farinon, J. Kahlbow, V. Volkov, M. Caamaño, W. N. Catford, A. Ignatov, S. Pietri, Carlos A. Bertulani, V. Panin, C. Langer, A. Kelic-Heil, O. Sorlin, Stefanos Paschalis, J. M. Boillos, Enrique Casarejos, J. Hagdahl, Iris Dillmann, M Vandebrouck, O. Ershova, K. Boretzky, A. Henriques, Roy Crawford Lemmon, J. S. Winfield, J. Benlliure, M. Labiche, Vladimir Avdeichikov, Enrique Nácher, H. Weick, Thomas Nilsson, F. Wamers, Rituparna Kanungo, M. Holl, C. Caesar, P. Velho, Håkan T Johansson, G. Ribeiro, Pavel Golubev, F. M. Marqués, M. Heine, Andreas Zilges, Hans Geissel, J. Enders, D. Galaviz, Daniel Bemmerer, Deniz Savran, Marielle Chartier, María José García Borge, Haik Simon, M. Freer, J. Taylor, Nasser Kalantar-Nayestanaki, Olof Tengblad, C. Wheldon, C. Nociforo, A. Revel, H. Alvarez-Pol, Joakim Cederkäll, Thomas Aumann, Rene Reifarth, L. Chulkov, J. Marganiec, Mikhail V. Zhukov, D. Yakorev, Björn Jonson, M. Röder, Philip Woods, R. Plag, U. Datta Pramanik, Andreas Wagner, R. Gernhäuser, E. Cravo, Y. Togano, H. Scheit, N. Kurz, M. Heil, Grand Accélérateur National d'Ions Lourds ( GANIL ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de physique corpusculaire de Caen ( LPCC ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Ecole Nationale Supérieure d'Ingénieurs de Caen ( ENSICAEN ), Normandie Université ( NU ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Institut Pluridisciplinaire Hubert Curien ( IPHC ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ), R3B, Technische Universität Darmstadt, Federal Ministry of Education and Research (Germany), National Science Foundation (US), Department of Energy (US), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Valence (chemistry), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Aucun, General Physics and Astronomy, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Molecular physics, Pairing, 0103 physical sciences, Neutron, Física nuclear, Nuclear Experiment (nucl-ex), [ PHYS.NEXP ] Physics [physics]/Nuclear Experiment [nucl-ex], 010306 general physics, Nucleon, Nuclear Experiment, R3B radioactive beams nuclear structure neutron-rich Coulomb dissociation
Abstract: 6 pags., 4 figs., The emission of neutron pairs from the neutron-rich N = 12 isotones C-18 and O-20 has been studied by high-energy nucleon knockout from N-19 and O-21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N-19(-1p)18C*-> C-16 + n + n is clearly dominated by direct pair emission. The two- neutron correlation strength, the largest ever observed, suggests the predominance of a C-14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O-21(-1n)O-20*-> O-18 + n + n, attributed to its formation through the knockout of a deeply bound neutron that breaks the O-16 core and reduces the number of pairs., This work was supported by the German Federal Ministry for Education and Research (BMBF Project No. 05P15RDFN1), and through the GSI-TU Darmstadt cooperation agreement. C. A. Bertulani acknowledges support by U.S. Department of Energy Grant No. DE-FG02-08ER41533 and U.S. National Science Foundation Grant No. 1415656.
Published: 2018
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41. Comparison of electromagnetic and nuclear dissociation of Ne-17

Author: H. O. U. Fynbo, Deniz Savran, F. Aksouh, Christoph Langer, D. Cortina-Gil, J. Hoffman, Mattias Lantz, Michael Heil, O. Kiselev, W. Ott, Achim Richter, Thomas Aumann, K. Riisager, R. Kulessa, Björn Jonson, C. Lehr, L. M. Fraile, Dieter H. H. Hoffmann, Ángel Perea, J. Marganiec, Carlos A. Bertulani, C. Nociforo, Marielle Chartier, C. Karagiannis, Thomas Nilsson, Stefan Typel, V. Panin, F. Wamers, Y. Aksyutina, Hans Geissel, K. Sümmerer, Ralf Plag, H. Emling, Stefanos Paschalis, S. Beceiro-Novo, N. Kurz, O. Ershova, K. Mahata, Roy Crawford Lemmon, C. Wimmer, J. V. Kratz, D. Galaviz, A. Chatillon, Herbert A. Simon, T. Le Bleis, Olof Tengblad, Helmut Weick, Håkan T Johansson, H. Alvarez-Pol, C. Muntz, Michael Wiescher, Yu. A. Litvinov, D. M. Rossi, C. Rodriguez-Tajes, Joachim Stroth, M. J. G. Borge, G. Schrieder, K. Boretzky, Rene Reifarth, L. Chulkov, Department of Energy (US), National Science Foundation (US), German Research Foundation, Federal Ministry of Education and Research (Germany), European Money Markets Institute, Helmholtz International Center for FAIR, Technische Universität Darmstadt, and Ministerio de Economía y Competitividad (España)
Subjects: Physics, COLLISIONS, Internal energy, 010308 nuclear & particles physics, 01 natural sciences, 7. Clean energy, STATE, Dissociation (chemistry), Coincidence, CAPTURE, Reaction rate, medicine.anatomical_structure, Fragmentation (mass spectrometry), 0103 physical sciences, medicine, Halo, Atomic physics, 010306 general physics, Ground state, DECAY, Nucleus
Abstract: 8 pags., 10 figs., 3 tabs., The Borromean drip-line nucleus Ne-17 has been suggested to possess a two-proton halo structure in its ground state. In the astrophysical rp-process, where the two-proton capture reaction O-15(2p,gamma) Ne-17 plays an important role, the calculated reaction rate differs by several orders of magnitude between different theoretical approaches. To add to the understanding of the Ne-17 structure we have studied nuclear and electromagnetic dissociation. A 500 MeV/u Ne-17 beam was directed toward lead, carbon, and polyethylene targets. Oxygen isotopes in the final state were measured in coincidence with one or two protons. Different reaction branches in the dissociation of Ne-17 were disentangled. The relative populations of s and d states in F-16 were determined for light and heavy targets. The differential cross section for electromagnetic dissociation (EMD) shows a continuous internal energy spectrum in the three-body system O-15 + 2p. The Ne-17 EMD data were compared to current theoretical models. None of them, however, yields satisfactory agreement with the experimental data presented here. These new data may facilitate future development of adequate models for description of the fragmentation process., This project is supported by NAVI, GSI-TU Darmstadt cooperation, HIC for FAIR, EMMI, and BMBF and from DFG through Grant No. SFB1245 and from BMBF via Project No. 05P15RDFN1, and from the Spanish Ministry by research grant FPA2015-64969-P. C.A.B. acknowledges support by the US DOE Grant No. DE-FG02-08ER41533 and the US NSF Grant No. 1415656.
Published: 2018
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42. Quasifree ( p,pN ) scattering of light neutron-rich nuclei near N=14

Author: Roy Crawford Lemmon, M. Röder, Rituparna Kanungo, P. Cabanelas, M. Heil, S. Pietri, Hans Geissel, E. Y. Nikolskii, A. Movsesyan, J. Marganiec, O. Ershova, J. Enders, N. Kurz, V. Volkov, K. Boretzky, Iris Dillmann, Stefanos Paschalis, H. Scheit, F. Farinon, A. Estrade, Vladimir Avdeichikov, R. Plag, G. L. Wilson, A. Najafi, L. M. Fraile, V. Panin, A. M. Moro, D. Jurčiukonis, Simon Lindberg, Catherine Rigollet, Kai Zuber, U. Datta Pramanik, A. Henriques, J. Benlliure, F. Wamers, D. Yakorev, Carlos A. Bertulani, María José García Borge, J. S. Winfield, C. Langer, Andreas Zilges, I. Syndikus, A. Kelic-Heil, A. Deltuva, Thomas Nilsson, T. Le Bleis, M. Heine, G. Ribeiro, E. Cravo, D. Cortina-Gil, L. Atar, Nasser Kalantar-Nayestanaki, Mikhail V. Zhukov, Daniel Bemmerer, C. Wheldon, Marine Vandebrouck, D. Galaviz, Thomas Aumann, Y. Togano, Andreas Martin Heinz, O. Sorlin, Björn Jonson, M. Holl, T. Kröll, Andreas Wagner, Joakim Cederkäll, S. Beceiro-Novo, Ángel Perea, Enrique Nácher, Z. Elekes, H. Weick, B. Fernández-Domínguez, Philip Woods, Håkan T Johansson, K. Göbel, R. Gernhäuser, B. Pietras, Deniz Savran, Pavel Golubev, Haik Simon, M. Freer, Olof Tengblad, Rene Reifarth, Tanja Heftrich, C. Nociforo, W. N. Catford, D. Rossi, H. Alvarez-Pol, A. Ignatov, L. Chulkov, C. Caesar, J. Taylor, P. Velho, R. Crespo, A. Knyazev, R. Thies, Jorge Machado, Marina Petri, J. M. Boillos, J. Hagdahl, A. Hufnagel, M. Labiche, P. Díaz Fernández, Marielle Chartier, M. Caamaño, and Enrique Casarejos
Subjects: Physics, Proton, Inverse kinematics, 010308 nuclear & particles physics, Scattering, Nuclear Theory, Inverse, 01 natural sciences, Light scattering, Nuclear physics, Momentum, 0103 physical sciences, Neutron, Nuclear Experiment, 010306 general physics, Beam (structure)
Abstract: Background: For many years, quasifree scattering reactions in direct kinematics have been extensively used to study the structure of stable nuclei, demonstrating the potential of this approach. The (RB)-B-3 collaboration has performed a pilot experiment to study quasifree scattering reactions in inverse kinematics for a stable C-12 beam. The results from that experiment constitute the first quasifree scattering results in inverse and complete kinematics. This technique has lately been extended to exotic beams to investigate the evolution of shell structure, which has attracted much interest due to changes in shell structure if the number of protons or neutrons is varied. Purpose: In this work we investigate for the first time the quasifree scattering reactions (p, pn) and (p, 2p) simultaneously for the same projectile in inverse and complete kinematics for radioactive beams with the aim to study the evolution of single-particle properties from N = 14 to N = 15. Method: The structure of the projectiles O-23, O-22, and N-21 has been studied simultaneously via (p, pn) and (p, 2p) quasifree knockout reactions in complete inverse kinematics, allowing the investigation of proton and neutron structure at the same time. The experimental data were collected at the (RB)-B-3-LAND setup at GSI at beam energies of around 400 MeV/u. Two key observables have been studied to shed light on the structure of those nuclei: the inclusive cross sections and the corresponding momentum distributions. Conclusions: The knockout reactions (p, pn) and (p, 2p) with radioactive beams in inverse kinematics have provided important and complementary information for the study of shell evolution and structure. For the (p, pn) channels, indications of a change in the structure of these nuclei moving from N = 14 to N = 15 have been observed, i.e., from the 0d(5/2) shell to the 1s(1/2). This supports previous observations of a subshell closure at N = 14 for neutron-rich oxygen isotopes and its weakening for the nitrogen isotopes.
Published: 2018
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43. Quasifree ( p , 2p ) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength

Author: Rene Reifarth, J. Kahlbow, E. Y. Nikolskii, R. Thies, Jorge Machado, M. Heine, A. Estrade, Marina Petri, G. Ribeiro, J. Taylor, Daniel Bemmerer, M. A. Najafi, Haik Simon, M. Freer, Olof Tengblad, Enrique Casarejos, H. Alvarez-Pol, Kai Zuber, F. Farinon, C. Nociforo, D. Rossi, Nasser Kalantar-Nayestanaki, C. Wheldon, Thomas Aumann, K. Boretzky, L. Chulkov, Andreas Martin Heinz, C. Caesar, Vladimir Avdeichikov, Tanja Heftrich, J. M. Boillos, J. Hagdahl, V. Panin, D. Galaviz Redondo, Ángel Perea, T. Kröll, Joakim Cederkäll, A. Ignatov, Carlos A. Bertulani, N. Kurz, A. Hufnagel, M. Labiche, S. Pietri, V. Volkov, P. Díaz Fernández, Mikhail V. Zhukov, G. L. Wilson, Simon Lindberg, Carlo Barbieri, I. Syndikus, J. Benlliure, F. Wamers, M. Heil, Marine Vandebrouck, Catherine Rigollet, M. Caamaño, Enrique Nácher, H. Weick, S. Beceiro-Novo, C. Langer, O. Ershova, A. Kelic-Heil, P. Velho, A. Henriques, J. S. Winfield, Thomas Nilsson, A. Knyazev, E. Cravo, Håkan T Johansson, R. Crespo, María José García Borge, Pavel Golubev, O. Sorlin, H. Scheit, Marielle Chartier, M. Holl, Deniz Savran, I. Dillmann, Stefanos Paschalis, D. Yakorev, Y. Togano, J. Marganiec-Gałązka, T. Le Bleis, D. Cortina-Gil, Rituparna Kanungo, Hans Geissel, L. Atar, A. Movsesyan, L. M. Fraile, Björn Jonson, Philip Woods, Andreas Wagner, R. Gernhäuser, Andreas Zilges, J. Enders, R. Lemmon, M. Röder, Z. Elekes, K. Göbel, R. Plag, and W. N. Catford
Subjects: Physics, Range (particle radiation), 010308 nuclear & particles physics, Eikonal equation, media_common.quotation_subject, Nuclear Theory, Ab initio, General Physics and Astronomy, chemistry.chemical_element, 7. Clean energy, 01 natural sciences, Asymmetry, Oxygen, Isotopes of oxygen, Nuclear physics, chemistry, Isospin, 0103 physical sciences, Particle, Nuclear Experiment, 010306 general physics, media_common
Abstract: Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R3B/LAND setup with incident beam energies in the range of 300-450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type OA(p,2p)NA-1 have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.
Published: 2018
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44. Design studies for the NeuLAND VETO detector

Author: D. Kresan, Catherine Rigollet, C. A. Douma, Igor Gašparić, J. Mayer, Nasser Kalantar-Nayestanaki, K. Boretzky, and Research unit Nuclear & Hadron Physics
Subjects: Physics, History, Scintillation, 010308 nuclear & particles physics, Scattering, Physics::Instrumentation and Detectors, Detector, Scintillator, 01 natural sciences, Signal, Charged particle, Computer Science Applications, Education, Nuclear physics, 0103 physical sciences, Neutron detection, Neutron, High Energy Physics::Experiment, 010306 general physics, Nuclear Experiment, R3B, NeuLAND, Background elimination, VETO
Abstract: NeuLAND (New Large-Area Neutron Detector) is the neutron detector for the R3B-experiment (Reactions with Relativistic Radioactive Beams) at FAIR (Facility for Anti-proton and Ion Research). NeuLAND is a fully active detector composed of plastic scintillator bars. Neutrons are detected by the production of charged particles in the scintillators through hadronic scattering. These charged particles are then detected by their scintillation light. Due to the highly granular design of NeuLAND, the primary neutron interaction points can be accurately reconstructed. These reconstructed points contribute to a kinematically complete reconstruction of reactions with relativistic heavy-ion beams in the target, the goal of the R3B-experiment. However, charged particles produced by scattering on other parts of the R3B-setup may providea significant background. To distinguish the target neutrons from the background, a VETO detector could be placed in front of NeuLAND. This VETO detector is a single plane of thin plastic scintillator bars. It, therefore, provides a high detection efficiency for background particles, but a low detection efficiency for neutrons. For every signal in the VETO, NeuLAND signals can be analyzed with respect to their correlation to the VETO signal and can be eliminated from the further neutron analysis. In this paper, the design of this VETO detector is discussed.
Published: 2018

45. Low-lying dipole response in the unstable Ni70 nucleus

Author: A. Giaz, P. Doornenbal, F. C. L. Crespi, Takashi Nakamura, Ryo Taniuchi, C. Caesar, Hua-Lei Wang, Noritsugu Nakatsuka, S. Ceruti, R. Avigo, F. Camera, Naoki Fukuda, Shoko Koyama, H. Baba, Hideaki Otsu, O. Wieland, David Steppenbeck, Atsumi Saito, H. Scheit, J. Tsubota, Satoshi Takeuchi, K. Yoneda, S. R. Banerjee, Masafumi Matsushita, Yoshiaki Shiga, T. Ozaki, B. Million, Toshiyuki Sumikama, Thomas Aumann, Susumu Shimoura, Yosuke Kondo, A. Bracco, G. Benzoni, Hiroyoshi Sakurai, T. Motobayashi, Kazuo Ieki, M. Shikata, V. Derya, J. Tscheuschner, T. Kubo, Masanori Nishimura, Yasuhiro Togano, K. Boretzky, F. Schindler, Kathrin Wimmer, Nagao Kobayashi, P. Schrock, and Si-Ge Chen
Subjects: Physics, Dipole, medicine.anatomical_structure, 010308 nuclear & particles physics, 0103 physical sciences, medicine, Atomic physics, 010306 general physics, 01 natural sciences, Nucleus, Lying
Published: 2018

46. Effective proton-neutron interaction near the drip line from unbound states in F25,26

Author: R. Crespo, Hans Geissel, Ralf Plag, J. Benlliure, Jason D. Holt, H. Hergert, Marine Vandebrouck, Christoph Langer, J. M. Boillos, Z. Elekes, J. Hagdahl, T. Kröll, J. Taylor, J. S. Winfield, A. Kelic-Heil, C. Caesar, Björn Jonson, Rene Reifarth, Roman Gernhäuser, A. Ignatov, D. M. Rossi, D. Galaviz, Joachim Enders, L. Chulkov, Deniz Savran, Ángel Perea, A. Lepailleur, F. Farinon, M. Heine, M. A. Najafi, Mikhail V. Zhukov, Nasser Kalantar-Nayestanaki, Andreas Wagner, T. Le Bleis, J. Kahlbow, Daniel Bemmerer, R. Kanungo, P. Velho, E. Y. Nikolskii, O. Sorlin, C. Wheldon, Thomas Aumann, M. Caamaño, D. Cortina-Gil, Stefanos Paschalis, Andreas Martin Heinz, L. Atar, Iris Dillmann, C. Nociforo, A. Henriques, R. Thies, Jorge Machado, O. Ershova, V. Panin, Marina Petri, Joakim Cederkäll, M. Holl, E. Cravo, Thomas Nilsson, A. Estrade, V. Volkov, W. N. Catford, Olof Tengblad, Vladimir Avdeichikov, Martin Freer, Marielle Chartier, F. Wamers, Simon Lindberg, M. J. G. Borge, Kai Zuber, Kathrin Göbel, Enrique Nácher, M. Röder, U. Datta Pramanik, Catherine Rigollet, H. Alvarez-Pol, Julien Gibelin, K. Boretzky, Yasuhiro Togano, M. Heil, I. Syndikus, L. M. Fraile, P. Díaz Fernández, A. Knyazev, S. R. Stroberg, S. Beceiro-Novo, Achim Schwenk, Tanja Heftrich, A. Movsesyan, D. Yakorev, A. Hufnagel, J. Marganiec, Helmut Weick, Håkan T Johansson, H. Scheit, Pavel Golubev, F. M. Marqués, Andreas Zilges, M. Labiche, G. L. Wilson, F. de Oliveira Santos, Carlos A. Bertulani, G. Ribeiro, P. J. Woods, S. Pietri, Enrique Casarejos, N. Kurz, Scott Bogner, Herbert A. Simon, and Roy Crawford Lemmon
Subjects: Physics, 010308 nuclear & particles physics, Binding energy, Ab initio, Resonance, 7. Clean energy, 01 natural sciences, Atomic mass, 0103 physical sciences, Bound state, Nuclear force, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Multiplet
Abstract: Background: Odd-odd nuclei, around doubly closed shells, have been extensively used to study proton-neutron interactions. However, the evolution of these interactions as a function of the binding energy, ultimately when nuclei become unbound, is poorly known. The F-26 nucleus, composed of a deeply bound pi 0d(5/2) proton and an unbound v0d(3/2) neutron on top of an O-24 core, is particularly adapted for this purpose. The coupling of this proton and neutron results in a J(pi) = 1(1)(+) - 4(1)(+) multiplet, whose energies must be determined to study the influence of the proximity of the continuum on the corresponding proton-neutron interaction. The J(pi) = 1(1)(+), 2(1)(+), 4(1)(+) bound states have been determined, and only a clear identification of the J(pi) = 3(1)(+) is missing. Purpose: We wish to complete the study of the J(pi) = 1(1)(+) - 4(1)(+) multiplet in F-26, by studying the energy and width of the J(pi) = 3(1)(+) unbound state. The method was first validated by the study of unbound states in F-25, for which resonances were already observed in a previous experiment. Method: Radioactive beams of Ne-26 and Ne-27, produced at about 440AMeV by the fragment separator at the GSI facility were used to populate unbound states in F-25 and F-26 via one-proton knockout reactions on a CH2 target, located at the object focal point of the (RB)-B-3/LAND setup. The detection of emitted. rays and neutrons, added to the reconstruction of the momentum vector of the A - 1 nuclei, allowed the determination of the energy of three unbound states in F-25 and two in F-26. Results: Based on its width and decay properties, the first unbound state in F-25, at the relative energy of 49(9) keV, is proposed to be a J(pi) = 1/ 2(-) arising from a p1/2 proton- hole state. In F-26, the first resonance at 323(33) keV is proposed to be the J(pi) = 3(1)(+) member of the J(pi) = 1(1)(+) - 4(1)(+) multiplet. Energies of observed states in F-25,F-26 have been compared to calculations using the independent-particle shell model, a phenomenological shell model, and the ab initio valence-space in-medium similarity renormalization group method. Conclusions: The deduced effective proton- neutron interaction is weakened by about 30-40% in comparison to the models, pointing to the need for implementing the role of the continuum in theoretical descriptions or to a wrong determination of the atomic mass of F-26.
Published: 2017
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47. Measurements of the Dipole Polarizability of Neutron-Rich Unstable Nuclei

Author: P. Schrock, D. Rossi, K. Boretzky, Thomas Aumann, Andrea Horvat, and Fabia Schindler
Subjects: Physics, Dipole, Polarizability, Neutron, Atomic physics
Published: 2017
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48. Knockout and fragmentation reactions using a broad range of tin isotopes

Author: M. Caamaño, Hans Geissel, D. Pérez-Loureiro, A. Kelic-Heil, S. Pietri, Helmut Weick, J. S. Winfield, M. Takechi, Yu. A. Litvinov, Enrique Casarejos, J. Benlliure, J. Vargas, C. Paradela, A. Prochazka, D. Cortina-Gil, K. Boretzky, J. L. Rodriguez-Sanchez, J. Díaz-Cortes, Carlos A. Bertulani, M. Mostazo, H. Alvarez-Pol, Yassid Ayyad, S. Beceiro-Novo, J. Atkinson, A. Estrade, Thomas Aumann, and P. Díaz Fernández
Subjects: Physics, 010308 nuclear & particles physics, Nuclear Theory, Bench marking, 01 natural sciences, Nuclear physics, Fragmentation (mass spectrometry), 0103 physical sciences, Isotopes of tin, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Excitation
Abstract: Production cross sections of residual nuclei obtained by knockout and fragmentation reactions of different tin isotopes accelerated at 1A GeV have been measured with the fragment separator (FRS) at GSI, Darmstadt. The new measurements are used to investigate the neutron-excess dependence of the neutron- and proton-knockout cross sections. These cross sections are compared toGlauber model calculations coupled to a nuclear de-excitation code in order to investigate the role of the remnant excitations. This bench marking shows an overestimation of the cross sections for the removal of deeply bound nucleons. A phenomenological increase in the excitation energy induced in the remnants produced in these cases allows us to reproduce the measured cross sections.
Published: 2017
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49. Ground-state configuration of neutron-rich Al-35 via Coulomb breakup

Author: Reiner Kruecken, Heiko Scheit, T. Le Bleis, V. Panin, M. V. Ricciardi, Andreas Wagner, Helmut Weick, D. Cortina-Gil, Håkan T Johansson, Nasser Kalantar-Nayestanaki, J. Taylor, Thomas Nilsson, Yasuhiro Togano, W. N. Catford, Hans Geissel, Thomas Aumann, C. Scheidenberger, T. Kroell, F. Wamers, P. Díaz Fernández, D. M. Rossi, O. Ershova, G. Münzenberg, S. Chakraborty, Björn Jonson, M. A. Najafi, Ralf Plag, L. M. Fraile, Marielle Chartier, Stefan Typel, S. Beceiro-Novo, J. Marganiec, C. Nociforo, Rene Reifarth, Ushasi Datta, K. Boretzky, Yutaka Utsuno, G. de Angelis, Yvonne Leifels, B. V. Carlson, C. Langer, Anisur Rahaman, Herbert A. Simon, H. Emling, Catherine Rigollet, D. González-Díaz, C. Caesar, J. S. Winfield, and Research unit Nuclear & Hadron Physics
Subjects: Physics, ISLAND, IONS, COLLISIONS, Valence (chemistry), NUCLEI, Ion, N=20 SHELL CLOSURE, Atomic orbital, Excited state, EXCITATION, Coulomb, ISOTOPES, Neutron, INVERSION, Atomic physics, Nucleon, Ground state, EMISSION, MASS MEASUREMENTS
Abstract: The ground-state configuration of Al-35 has been studied via Coulomb dissociation (CD) using the LAND-FRS setup (GSI, Darmstadt) at a relativistic energy of similar to 403 MeV/nucleon. The measured inclusive differential CD cross section for Al-35, integrated up to 5.0 MeV relative energy between the Al-34 core and the neutron using a Pb target, is 78(13) mb. The exclusive measured CD cross section that populates various excited states of 34Al is 29(7) mb. The differential CD cross section of Al-35 -> Al-34 + n has been interpreted in the light of a direct breakup model, and it suggests that the possible ground-state spin and parity of Al-35 could be, tentatively, 1/2+ or 3/2(+) or 5/2(+). The valence neutrons, in the ground state of Al-35, may occupy a combination of either l = 3,0 or l = 1,2 orbitals coupled with the Al-34 core in the ground and isomeric state(s), respectively. This hints of a particle-hole configuration of the neutron across the magic shell gaps at N = 20,28 which suggests narrowing the magic shell gap. If the 5/2+ is the ground-state spin-parity of Al-35 as suggested in the literature, then the major ground-state configuration of Al-35 is a combination of Al-34(g. s.; 4(-)) circle times upsilon(p3/2) and Al-34(isomer; 1(+)) circle times upsilon(d3/2) states. The result from this experiment has been compared with that from a previous knockout measurement and a calculation using the SDPF-M interaction.
Published: 2017

50. Determination of the neutron-capture rate of C17 for r -process nucleosynthesis

Author: Håkan T Johansson, Pavel Golubev, Enrique Casarejos, T. Adachi, J. Van de Walle, Ethan Uberseder, G. L. Wilson, Y. Aksyutina, S. Beceiro-Novo, J. Enders, Ángel Perea, F. Farinon, C. Langer, R. Knöbel, J. Benlliure, O. Lepyoshkina, Marielle Chartier, A. Kelic-Heil, F. Wamers, N. I. Ashwood, A. Najafi, M. Barr, Kai Zuber, J. Alcantara, Tanja Heftrich, T. Le Bleis, A. Henriques, G. Ickert, J. S. Winfield, D. Cortina-Gil, Thomas Nilsson, G. Ribeiro, Hans Geissel, S. Pietri, Haik Simon, M. Freer, Anisur Rahaman, C. Caesar, Olof Tengblad, C. Nociforo, Stefanos Paschalis, O. Ershova, D. Rossi, Y. Togano, Stefan Typel, S. Chakraborty, A. Movsesyan, O. Sorlin, K. Boretzky, K. Riisager, P. Díaz Fernández, Andreas Zilges, A. Ignatov, Meng-Ru Wu, P. Velho, Vladimir Avdeichikov, Simon Lindberg, A. Prochazka, Catherine Rigollet, Mario Weigand, M. Caamaño, B. Streicher, J. Taylor, Z. Elekes, W. N. Catford, S. Terashima, K. Göbel, V. Panin, Bo Jakobsson, M. Heil, J. Hagdahl, Carlos A. Bertulani, M. V. Ricciardi, Björn Jonson, Philip Woods, M. Labiche, M. Freudenberger, L. M. Fraile, R. Plag, U. Datta Pramanik, S. Altstadt, Gabriel Martínez-Pinedo, R. Thies, Jorge Machado, T. Neff, Marina Petri, R. Crespo, H. Weick, M. Holl, J. Kurcewicz, Andreas Wagner, H. Scheit, H. Alvarez-Pol, R. Gernhäuser, H. O. U. Fynbo, Nasser Kalantar-Nayestanaki, G. Rastrepina, J. Sanchez del Rio, D. Galaviz, C. Wheldon, Thomas Aumann, Deniz Savran, N. Kurz, Andreas Martin Heinz, M. Röder, T. Kröll, V. Stoica, M. Mostazo, V. Volkov, M. Heine, Daniel Bemmerer, I. Dillmann, Joakim Cederkäll, D. Yakorev, Mikhail V. Zhukov, V. Maroussov, A. Estrade, J. Marganiec, Rene Reifarth, G. Burgunder, Roy Crawford Lemmon, C. Wimmer, Rituparna Kanungo, L. Chulkov, R. Krücken, D. Gonzalez Diaz, and María José García Borge
Subjects: Physics, education.field_of_study, 010308 nuclear & particles physics, Population, 7. Clean energy, 01 natural sciences, Spectral line, Nuclear physics, Neutron capture, Nucleosynthesis, Excited state, 0103 physical sciences, Coulomb, r-process, Atomic physics, Nuclear Experiment, 010306 general physics, education, Ground state
Abstract: With the R$^{3}$B-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of $^{18}$C at a projectile energy around 425~AMeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of $^{17}$C into the ground state of $^{18}$C. Those data have been used to constrain theoretical calculations for transitions populating excited states in $^{18}$C. This allowed to derive the astrophysical cross section $\sigma^{*}_{\mathrm{n}\gamma}$ accounting for the thermal population of $^{17}$C target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures $T_{9}\leq{}1$~GK. Network simulations with updated neutron-capture rates and hydrodynamics according to the neutrino-driven wind model as well as the neutron-star merger scenario reveal no pronounced influence of neutron capture of $^{17}$C on the production of second- and third-peak elements in contrast to earlier sensitivity studies.
Published: 2017
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