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414 results on '"Auranen, K."'

1. Isospin symmetry in the $T = 1, A = 62$ triplet

Author

Wimmer, K., Ruotsalainen, P., Lenzi, S. M., Poves, A., Hüyük, T., Browne, F., Doornenbal, P., Koiwai, T., Arici, T., Auranen, K., Bentley, M. A., Cortés, M. L., Delafosse, C., Eronen, T., Ge, Z., Grahn, T., Greenlees, P. T., Illana, A., Imai, N., Joukainen, H., Julin, R., Jungclaus, A., Jutila, H., Kankainen, A., Kitamura, N., Longfellow, B., Louko, J., Lozeva, R., Luoma, M., Mauss, B., Napoli, D. R., Niikura, M., Ojala, J., Pakarinen, J., Pereira-Lopez, X., Rahkila, P., Recchia, F., Sandzelius, M., Sarén, J., Taniuchi, R., Tann, H., Uthayakumaar, S., Uusitalo, J., Vaquero, V., Wadsworth, R., Zimba, G., and Yajzey, R.

Subjects
Nuclear Experiment
Abstract

Excited states in the $T_z = 0, -1$ nuclei $^{62}$Ga and $^{62}$Ge were populated in direct reactions of relativistic radioactive ion beams at the RIBF. Coincident \grays were measured with the DALI2$^+$ array and uniquely assigned to the $A=62$ isobars. In addition, $^{62}$Ge was also studied independently at JYFL-ACCLAB using the ${}^{24}$Mg(${}^{40}$Ca,$2n$)${}^{62}$Ge fusion-evaporation reaction. The first excited $T=1, J^\pi =2^+$ states in $^{62}$Ga and $^{62}$Ge were identified at $979(1)$ and $965(1)$~keV, respectively, resolving discrepant interpretations in the literature. States beyond the first $2^+$ state in $^{62}$Ge were also identified for the first time in the present work. The results are compared with shell-model calculations in the $fp$ model space. Mirror and triplet energy differences are analyzed in terms of individual charge-symmetry and charge-independence breaking contributions. The MED results confirm the shrinkage of the $p$-orbits' radii when they are occupied by at least one nucleon on average., Comment: aceepted Phys. Lett. B

Published
2023

2. Decay spectroscopy at the two-proton drip line: Radioactivity of the new nuclides 160Os and 156W

Author

Briscoe, AD, Page, RD, Uusitalo, J, Joss, DT, AlAqeel, MAM, Alayed, B, Andel, B, Antalic, S, Auranen, K, Ayatollahzadeh, H, Badran, H, Barber, L, Beeton, G, Birova, M, Bogdanoff, V, Clark, RM, Cubiss, JG, Cullen, DM, Deary, J, Forsberg, U, Grahn, T, Greenlees, PT, Hilton, JB, Illana, A, Joukainen, H, Judson, DS, Julin, R, Jutila, H, Keatings, JM, Labiche, M, Leino, M, Lewis, MC, Louko, J, Luoma, M, Martel, I, McCarter, A, McKee, PP, Mosat, P, Nathaniel, SN, Neuvonen, O, O'Donnell, D, Ojala, J, Page, CAA, Plaza, AM, Pakarinen, J, Papadakis, P, Parr, E, Partanen, J, Rahkila, P, Ruotsalainen, P, Sandzelius, M, Sarén, J, Saygi, B, Smallcombe, J, Smith, JF, Sorri, J, Sullivan, CM, Szwec, S, Tann, H, Tolosa-Delgado, A, Uusikylä, E, Venhart, M, Waring, LJ, and Zimba, G

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Mathematical Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics, Mathematical sciences, Physical sciences
Published
2023

3. Experimental Study of the $^{\textbf{38}}$S Excited Level Scheme

Author

Hoffman, C. R., Lubna, R. S., Rubino, E., Tabor, S. L., Auranen, K., Bender, P. C., Campbell, C. M., Carpenter, M. P., Chen, J., Gott, M., Greene, J. P., Hoff, D. E. M., Huang, T., Iwasaki, H., Kondev, F. G., Lauritsen, T., Longfellow, B., Santamaria, C., Seweryniak, D., Tang, T. L., Wilson, G. L., Wu, J., and Zhu, S.

Subjects
Nuclear Experiment
Abstract

Information on the $^{38}$S level scheme was expanded through experimental work utilizing a fusion-evaporation reaction and in-beam $\gamma$-ray spectroscopy. Prompt $\gamma$-ray transitions were detected by the Gamma-Ray Energy Tracking Array (GRETINA) and recoiling $^{38}$S residues were selected by the Fragment Mass Analayzer (FMA). Tools based on machine-learning techniques were developed and deployed for the first time in order to enhance the unique selection of $^{38}$S residues and identify any associated $\gamma$-ray transitions. The new level information, including the extension of the even-spin yrast sequence through $J^{\pi} = 8^{(+)}$, was interpreted in terms of a basic single-particle picture as well shell-model calculations which incorporated the empirically derived FSU interaction. A comparison between the properties of the yrast states in the even-$Z$ $N=22$ isotones from $Z=14$ to $20$, and for $^{36}$Si-$^{38}$S in particular, was also presented with an emphasis on the role and influence of the neutron $1p_{3/2}$ orbital on the structure in the region.

Published
2023
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4. Nuclear rotation at the fission limit in Rf254

Author

Seweryniak, D, Huang, T, Auranen, K, Ayangeakaa, AD, Back, BB, Carpenter, MP, Chowdhury, P, Clark, RM, Copp, PA, Favier, Z, Hauschild, K, He, X-T, Khoo, TL, Kondev, FG, Korichi, A, Lauritsen, T, Li, J, Morse, C, Potterveld, DH, Savard, G, Stolze, S, Wu, J, Zhang, J, and Xu, Y-F

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract

A ground-state rotational band in the fissile nucleus Rf254 was observed for the first time. Levels up to spin 14 and excitation energy of 1.56 MeV were observed. The Rf254 nuclei were produced using the Pb206(Ti50,2n) fusion-evaporation reaction. It is the weakest reaction channel ever studied using in-beam γ-ray spectroscopic methods. The reaction products were separated from the beam in the Argonne gas-filled analyzer (AGFA). The Rf254 nuclei were implanted into a double-sided Si strip detector at the AGFA focal plane and tagged with subsequent ground-state spontaneous fission decays using temporal and spatial correlations. Prompt γ rays in coincidence with the Rf254 recoils were detected in the Gammasphere array of Ge detectors. In order to identify the ground-state rotational band in Rf254, a method for identifying rotational bands in low statistics γ-ray spectra was developed. The deduced Rf254 kinematic moment of inertia is smaller compared to neighboring even-even nuclei. This is most likely associated with a slightly lower quadrupole deformation and stronger pairing correlations in Rf254. The behavior of the moment of inertia as a function of rotational frequency is similar to that of the lighter N=150 isotones Fm250 and No252.

Published
2023

5. First direct measurement of the $^{13}$N($\alpha$,$p$)$^{16}$O reaction relevant for core-collapse supernovae nucleosynthesis

Author

Jayatissa, H., Avila, M. L., Rehm, K. E., Talwar, R., Mohr, P., Auranen, K., Chen, J., Gorelov, D. A., Hoffman, C. R., Jiang, C. L., Kay, B. P., Kuvin, S. A., and Santiago-Gonzalez, D.

Subjects
Nuclear Experiment
Abstract

Understanding the explosion mechanism of a core-collapse supernova (CCSN) is important to accurately model CCSN scenarios for different progenitor stars using model-observation comparisons. The uncertainties of various nuclear reaction rates relevant for CCSN scenarios strongly affect the accuracy of these stellar models. Out of these reactions, the $^{13}$N($\alpha$,$p$)$^{16}$O reaction has been found to affect various stages of a CCSN at varying temperatures. This work presents the first direct measurement of the $^{13}$N($\alpha$,$p$)$^{16}$O reaction performed using a 34.6 MeV beam of radioactive $^{13}$N ions and the active-target detector MUSIC (MUlti-Sampling Ionization Chamber) at Argonne National Laboratory. The resulting total $^{13}$N($\alpha$,$p$)$^{16}$O reaction cross sections from this measurement in the center-of-mass energy range of 3.26 - 6.02 MeV are presented and compared with calculations using the Hauser-Feshbach formalism. Uncertainties in the reaction rate have been dramatically reduced at CCSN temperatures., Comment: References 27 and 31 has been changed

Published
2022
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6. First observation of high-$K$ isomeric states in $^{249}$Md and $^{251}$Md

Author

Goigoux, T., Theisen, Ch., Sulignano, B., Airiau, M., Auranen, K., Badran, H., Briselet, R., Calverley, T., Cox, D., Déchery, F., Bisso, F. Defranchi, Drouart, A., Favier, Z., Gall, B., Grahn, T., Greenlees, P. T., Hauschild, K., Herzáň, A., Herzberg, R. -D., Jakobsson, U., Julin, R., Juutinen, S., Konki, J., Leino, M., Lightfoot, A., Lopez-Martens, A., Mistry, A., Nieminen, P., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Rey-Herme, E., Rubert, J., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., Sorri, J., Stolze, S., Uusitalo, J., Vandebrouck, M., Ward, A., Zielińska, M., Jachimowicz, P., Kowal, M., and Skalski, J.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Decay spectroscopy of the odd-proton nuclei $^{249}$Md and $^{251}$Md has been performed. High-$K$ isomeric states were identified for the first time in these two nuclei through the measurement of their electromagnetic decay. An isomeric state with a half-life of $2.8(5)$ ms and an excitation energy $\geq 910$ keV was found in $^{249}$Md. In $^{251}$Md, an isomeric state with a half-life of $1.4(3)$ s and an excitation energy $\geq 844$ keV was found. Similarly to the neighbouring $^{255}$Lr, these two isomeric states are interpreted as 3 quasi-particle high-$K$ states and compared to new theoretical calculations. Excited nuclear configurations were calculated within two scenarios: via blocking nuclear states located in proximity to the Fermi surface or/and using the quasiparticle Bardeen-Cooper-Schrieffer method. Relevant states were selected on the basis of the microscopic-macroscopic model with a deformed Woods-Saxon potential. The most probable candidates for the configurations of $K$-isomeric states in Md nuclei are proposed.

Published
2021
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7. Shape Coexistence at Zero Spin in 64Ni Driven by the Monopole Tensor Interaction

Author

Mărginean, N., Little, D., Tsunoda, Y., Leoni, S., Janssens, R. V. F., Fornal, B., Otsuka, T., Michelagnoli, C., Stan, L., Crespi, F. C. L., Costache, C., Lica, R., Sferrazza, M., Turturica, A., Ayangeakaa, A. D., Auranen, K., Barani, M., Bender, P. C., Bottoni, S., Boromiza, M., Bracco, A., Călinescu, S., Campbell, C. M., Carpenter, M. P., Chowdhury, P., Ciemała, M., Cieplicka-Orynczak, N., Cline, D., Clisu, C., Crawford, H. L., Dinescu, I. E., Filipescu, D., Florea, N., Forney, A. M., Fracassetti, S., Gade, A., Gheorghe, I., Hayes, A. B., Harca, I., Henderson, J., Ionescu, A., Iskra, Ł. W., Jentschel, M., Kandzia, F., Kim, Y. H., Kondev, F. G., Korschinek, G., Köster, U., Krishichayan, Krzysiek, M., Lauritsen, T., Li, J., Mărginean, R., Maugeri, E. A., Mihai, C., Mihai, R. E., Mitu, A., Mutti, P., Negret, A., Niţă, C. R., Olăcel, A., Oprea, A., Pascu, S., Petrone, C., Porzio, C., Rhodes, D., Seweryniak, D., Schumann, D., Sotty, C., Stolze, S. M., Şuvăilă, R., Toma, S., Ujeniuc, S., Walters, W. B., Wu, C. Y., Wu, J., Zhu, S., and Ziliani, S.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The low-spin structure of the semimagic 64Ni nucleus has been considerably expanded: combining four experiments, several 0+ and 2+ excited states were identified below 4.5 MeV, and their properties established. The Monte Carlo shell model accounts for the results and unveils an unexpectedly complex landscape of coexisting shapes: a prolate 0+ excitation is located at a surprisingly high energy (3463 keV), with a collective 2+ state 286 keV above it, the first such observation in Ni isotopes. The evolution in excitation energy of the prolate minimum across the neutron N = 40 subshell gap highlights the impact of the monopole interaction and its variation in strength with N.

Published
2020
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8. In-beam gamma-ray and electron spectroscopy of $^{249,251}$Md

Author

Briselet, R., Theisen, Ch., Sulignano, B., Airiau, M., Auranen, K., Cox, D. M., Déchery, F., Drouart, A., Favier, Z., Gall, B., Goigoux, T., Grahn, T., Greenlees, P. T., Hauschild, K., Herzan, A., Herzberg, R. -D., Jakobsson, U., Julin, R., Juutinen, S., Konki, J., Leino, M., Lopez-Martens, A., Mistry, A., Nieminen, P., Pakarinen, J., Papadakis, P., Peura, P., Rahkila, P., Rey-Herme, E., Rubert, J., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., Sorri, J., Stolze, S., Uusitalo, J., Vandebrouck, M., Ward, A., Zielińska, M., Bally, B., Bender, M., and Ryssens, W.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The odd-$Z$ $^{251}$Md nucleus was studied using combined $\gamma$-ray and conversion-electron in-beam spectroscopy. Besides the previously observed rotational band based on the $[521]1/2^-$ configuration, another rotational structure has been identified using $\gamma$-$\gamma$ coincidences. The use of electron spectroscopy allowed the rotational bands to be observed over a larger rotational frequency range. Using the transition intensities that depend on the gyromagnetic factor, a $[514]7/2^-$ single-particle configuration has been inferred for this band, i.e., the ground-state band. A physical background that dominates the electron spectrum with an intensity of $\simeq$ 60% was well reproduced by simulating a set of unresolved excited bands. Moreover, a detailed analysis of the intensity profile as a function of the angular momentum provided a method for deriving the orbital gyromagnetic factor, namely $g_K = 0.69^{+0.19}_{-0.16}$ for the ground-state band. The odd-$Z$ $^{249}$Md was studied using $\gamma$-ray in-beam spectroscopy. Evidence for octupole correlations resulting from the mixing of the $\Delta l = \Delta j = 3$ $[521]3/2^-$ and $[633]7/2^+$ Nilsson orbitals were found in both $^{249,251}$Md. A surprising similarity of the $^{251}$Md ground-state band transition energies with those of the excited band of $^{255}$Lr has been discussed in terms of identical bands. Skyrme-Hartree-Fock-Bogoliubov calculations were performed to investigate the origin of the similarities between these bands.

Published
2020
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9. Evidence for rigid triaxial deformation in $^{76}$Ge from a model-independent analysis

Author

Ayangeakaa, A. D., Janssens, R. V. F., Zhu, S., Little, D., Henderson, J., Wu, C. Y., Hartley, D. J., Albers, M., Auranen, K., Bucher, B., Carpenter, M. P., Chowdhury, P., Cline, D., Crawford, H. L., Fallon, P., Forney, A. M., Gade, A., Hayes, A. B., Kondev, F. G., Krishichayan, Lauritsen, T., Li, J., Macchiavelli, A. O., Rhodes, D., Seweryniak, D., Stolze, S. M., Walters, W. B., and Wu, J.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

An extensive, model-independent analysis of the nature of triaxial deformation in $^{76}$Ge, a candidate for neutrinoless double-beta ($0\nu\beta\beta$) decay, was carried out following multi-step Coulomb excitation. Shape parameters deduced on the basis of a rotational-invariant sum-rule analysis provided considerable insight into the underlying collectivity of the ground-state and $\gamma$ bands. Both sequences were determined to be characterized by the same $\beta$ and $\gamma$ deformation parameter values. In addition, compelling evidence for low-spin, rigid triaxial deformation in $^{76}$Ge was obtained for the first time from the analysis of the statistical fluctuations of the quadrupole asymmetry deduced from the measured $E2$ matrix elements. These newly determined shape parameters are important input and constraints for calculations aimed at providing, with suitable accuracy, the nuclear matrix elements relevant to $0\nu\beta\beta$., Comment: 6 pages, 5 figures

Published
2019
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10. In-beam γ94-ray spectroscopy of γ94Ag

Author

Pereira-López, X., Bentley, M. A., Wadsworth, R., Ruotsalainen, P., Lenzi, S. M., Forsberg, U., Auranen, K., Blazhev, A., Cederwall, B., Grahn, T., Greenlees, P., Illana, A., Jenkins, D. G., Julin, R., Jutila, H., Juutinen, S., Liu, X., Llewelyn, R., Luoma, M., Moschner, K., Müller-Gatermann, C., Singh, B. S. Nara, Nowacki, F., Ojala, J., Pakarinen, J., Papadakis, P., Rahkila, P., Romero, J., Sandzelius, M., Sarén, J., Tann, H., Uthayakumaar, S., Uusitalo, J., Vega-Romero, J. G., Vilhena, J. M., Yajzey, R., Zhang, W., and Zimba, G.

Published
2023
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11. Production cross section and decay study of $^{243}$Es and $^{249}$Md

Author

Briselet, R., Theisen, Ch., Vandebrouck, M., Marchix, A., Airiau, M., Auranen, K., Badran, H., Boilley, D., Calverley, T., Cox, D., Déchery, F., Bisso, F. Defranchi, Drouart, A., Gall, B., Goigoux, T., Grahn, T., Greenlees, P. T., Hauschild, K., Herzan, A., Herzberg, R. D., Jakobsson, U., Julin, R., Juutinen, S., Konki, J., Leino, M., Lightfoot, A., Lopez-Martens, A., Mistry, A., Nieminen, P., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Rubert, J., Ruotsalainen, P., Sandzelius, M., Saren, J., Scholey, C., Sorri, J., Stolze, S., Sulignano, B., Uusitalo, J., Ward, A., and Zielińska, M.

Subjects
Nuclear Experiment
Abstract

In the study of the odd-$Z$, even-$N$ nuclei $^{243}$Es and $^{249}$Md, performed at the University of Jyv\"askyl\"a, the fusion-evaporation reactions $^{197}$Au($^{48}$Ca,2$n$)$^{243}$Es and $^{203}$Tl($^{48}$Ca,2$n$)$^{249}$Md have been used for the first time. Fusion-evaporation residues were selected and detected using the RITU gas-filled separator coupled with the focal-plane spectrometer GREAT. For $^{243}$Es, the recoil decay correlation analysis yielded a half-life of $24 \pm 3$s, and a maximum production cross section of $37 \pm 10$ nb. In the same way, a half-life of $26 \pm 1$ s, an $\alpha$ branching ratio of 75 $\pm$ 5%, and a maximum production cross section of 300 $\pm$ 80 nb were determined for $^{249}$Md. The decay properties of $^{245}$Es, the daughter of $^{249}$Md, were also measured: an $\alpha$ branching ratio of 54 $\pm$ 7% and a half-life of 65 $\pm$ 6 s. Experimental cross sections were compared to the results of calculations performed using the KEWPIE2 statistical fusion-evaporation code.

Published
2018
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12. Probing the single-particle character of rotational states in $^{19}$F using a short-lived isomeric beam

Author

Santiago-Gonzalez, D., Auranen, K., Avila, M. L., Ayangeakaa, A. D., Back, B. B., Bottoni, S., Carpenter, M. P., Chen, J., Deibel, C. M., Hood, A. A., Hoffman, C. R., Janssens, R. V. F., Jiang, C. L., Kay, B. P., Kuvin, S. A., Lauer, A., Schiffer, J. P., Sethi, J., Talwar, R., Wiedenhoever, I., Winkelbauer, J., and Zhu, S.

Subjects
Nuclear Experiment
Abstract

A beam containing a substantial component of both the $J^{\pi}=5^+$, $T_{1/2}=162$ ns isomeric state of $^{18}$F and its $1^+$, 109.77-min ground state has been utilized to study members of the ground-state rotational band in $^{19}$F through the neutron transfer reaction $(d$,$p)$ in inverse kinematics. The resulting spectroscopic strengths confirm the single-particle nature of the 13/2$^+$ band-terminating state. The agreement between shell-model calculations, using an interaction constructed within the $sd$ shell, and our experimental results reinforces the idea of a single-particle/collective duality in the descriptions of the structure of atomic nuclei.

Published
2018
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13. Isospin symmetry in the T = 1,A = 62 triplet

Author

Wimmer, K., primary, Ruotsalainen, P., additional, Lenzi, S.M., additional, Poves, A., additional, Hüyük, T., additional, Browne, F., additional, Doornenbal, P., additional, Koiwai, T., additional, Arici, T., additional, Auranen, K., additional, Bentley, M.A., additional, Cortés, M.L., additional, Delafosse, C., additional, Eronen, T., additional, Ge, Z., additional, Grahn, T., additional, Greenlees, P.T., additional, Illana, A., additional, Imai, N., additional, Joukainen, H., additional, Julin, R., additional, Jungclaus, A., additional, Jutila, H., additional, Kankainen, A., additional, Kitamura, N., additional, Longfellow, B., additional, Louko, J., additional, Lozeva, R., additional, Luoma, M., additional, Mauss, B., additional, Napoli, D.R., additional, Niikura, M., additional, Ojala, J., additional, Pakarinen, J., additional, Pereira-Lopez, X., additional, Rahkila, P., additional, Recchia, F., additional, Sandzelius, M., additional, Sarén, J., additional, Taniuchi, R., additional, Tann, H., additional, Uthayakumaar, S., additional, Uusitalo, J., additional, Vaquero, V., additional, Wadsworth, R., additional, Zimba, G., additional, and Yajzey, R., additional

Published
2023
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14. Decay spectroscopy at the two-proton drip line: Radioactivity of the new nuclides 160Os and 156W

Author

Briscoe, A.D., primary, Page, R.D., additional, Uusitalo, J., additional, Joss, D.T., additional, AlAqeel, M.A.M., additional, Alayed, B., additional, Andel, B., additional, Antalic, S., additional, Auranen, K., additional, Ayatollahzadeh, H., additional, Badran, H., additional, Barber, L., additional, Beeton, G., additional, Birova, M., additional, Bogdanoff, V., additional, Clark, R.M., additional, Cubiss, J.G., additional, Cullen, D.M., additional, Deary, J., additional, Forsberg, U., additional, Grahn, T., additional, Greenlees, P.T., additional, Hilton, J.B., additional, Illana, A., additional, Joukainen, H., additional, Judson, D.S., additional, Julin, R., additional, Jutila, H., additional, Keatings, J.M., additional, Labiche, M., additional, Leino, M., additional, Lewis, M.C., additional, Louko, J., additional, Luoma, M., additional, Martel, I., additional, McCarter, A., additional, McKee, P.P., additional, Mosat, P., additional, Nathaniel, S.N., additional, Neuvonen, O., additional, O'Donnell, D., additional, Ojala, J., additional, Page, C.A.A., additional, Plaza, A.M., additional, Pakarinen, J., additional, Papadakis, P., additional, Parr, E., additional, Partanen, J., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Saygi, B., additional, Smallcombe, J., additional, Smith, J.F., additional, Sorri, J., additional, Sullivan, C.M., additional, Szwec, S., additional, Tann, H., additional, Tolosa-Delgado, A., additional, Uusikylä, E., additional, Venhart, M., additional, Waring, L.J., additional, and Zimba, G., additional

Published
2023
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16. Spectroscopy of proton-rich 66^Se up to J^{\pi} = 6^+: isospin-breaking effect in the A = 66 isobaric triplet

Author

Ruotsalainen, P., Jenkins, D. G., Bentley, M. A., Auranen, K., Davies, P. J., Grahn, T., Greenlees, P. T., Henderson, J., Herzáň, A., Jakobsson, U., Joshi, P., Julin, R., Juutinen, S., Konki, J., Leino, M., Lotay, G., Nichols, A. J., Obertelli, A., Pakarinen, J., Partanen, J., Peura, P., Rahkila, P., Sandzelius, M., Sarén, J., Scholey, C., Sorri, J., Stolze, S., Uusitalo, J., and Wadsworth, R.

Subjects
Nuclear Experiment
Abstract

Candidates for three excited states in the 66^Se have been identified using the recoil-{\beta} tagging method together with a veto detector for charged-particle evaporation channels. These results allow a comparison of mirror and triplet energy differences between analogue states across the A = 66 triplet as a function of angular momentum. The extracted triplet energy differences follow the negative trend observed in the f_7/2 shell. Shell-model calculations indicate a continued need for an additional isospin non-conserving interaction in addition to the Coulomb isotensor part as a function of mass., Comment: Submitted to Physical Review Letters on Jul. 18, 2013. 5 pages, 3 figures

Published
2013
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17. Experimental study of the S38 excited level scheme

Author

Hoffman, C. R., primary, Lubna, R. S., additional, Rubino, E., additional, Tabor, S. L., additional, Auranen, K., additional, Bender, P. C., additional, Campbell, C. M., additional, Carpenter, M. P., additional, Chen, J., additional, Gott, M., additional, Greene, J. P., additional, Hoff, D. E. M., additional, Huang, T., additional, Iwasaki, H., additional, Kondev, F. G., additional, Lauritsen, T., additional, Longfellow, B., additional, Santamaria, C., additional, Seweryniak, D., additional, Tang, T. L., additional, Wilson, G. L., additional, Wu, J., additional, and Zhu, S., additional

Published
2023
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18. Properties of the new α -decaying isotope At190

Author

Kokkonen, H., primary, Auranen, K., additional, Uusitalo, J., additional, Eeckhaudt, S., additional, Grahn, T., additional, Greenlees, P. T., additional, Jones, P., additional, Julin, R., additional, Juutinen, S., additional, Leino, M., additional, Leppänen, A.-P., additional, Nyman, M., additional, Pakarinen, J., additional, Rahkila, P., additional, Sarén, J., additional, Scholey, C., additional, Sorri, J., additional, and Venhart, M., additional

Published
2023
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19. First observation of excited states in 120La and its impact on the shape evolution in the A ≈ 120 mass region

Author

Jodidar, P.M., Petrache, C.M., Lv, B.F., Lawrie, E.A., Astier, A., Guo, S., Zheng, K.K., Auranen, K., Briscoe, A.D., Grahn, T., Greenlees, P.T., Illana, A., Joukainen, H., Julin, R., Louko, J., Luoma, M., Jutila, H., Ojala, J., Pakarinen, J., Plaza, A.M., Rahkila, P., Ruotsalainen, P., Sarén, J., Tolosa-Delgado, A., Uusitalo, J., Zimba, G., Kuti, I., Krakó, A., Andreoiu, C., Joss, D.T., Page, R.D., Cederlöf, E.A., and Ertoprak, A.

Published
2024
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20. Octupole correlations in the N = Z + 2 = 56 110Xe nucleus

Author

Illana, A., Pérez-Vidal, R.M., Stramaccioni, D., Valiente-Dobón, J.J., Rodriguez, T.R., Robledo, L.M., Poves, A., Auranen, K., Beliuskina, O., Delafosse, C., Eronen, T., Ge, Z., Geldhof, S., Gins, W., Grahn, T., Greenlees, P.T., Joukainen, H., Julin, R., Jutila, H., Kankainen, A., Leino, M., Louko, J., Luoma, M., Nesterenko, D., Ojala, J., Pakarinen, J., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Uusitalo, J., and Zimba, G.L.

Published
2024
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24. In-beam $$\gamma $$-ray spectroscopy of $$^{94}$$Ag

Author

Pereira-López, X., primary, Bentley, M. A., additional, Wadsworth, R., additional, Ruotsalainen, P., additional, Lenzi, S. M., additional, Forsberg, U., additional, Auranen, K., additional, Blazhev, A., additional, Cederwall, B., additional, Grahn, T., additional, Greenlees, P., additional, Illana, A., additional, Jenkins, D. G., additional, Julin, R., additional, Jutila, H., additional, Juutinen, S., additional, Liu, X., additional, Llewelyn, R., additional, Luoma, M., additional, Moschner, K., additional, Müller-Gatermann, C., additional, Singh, B. S. Nara, additional, Nowacki, F., additional, Ojala, J., additional, Pakarinen, J., additional, Papadakis, P., additional, Rahkila, P., additional, Romero, J., additional, Sandzelius, M., additional, Sarén, J., additional, Tann, H., additional, Uthayakumaar, S., additional, Uusitalo, J., additional, Vega-Romero, J. G., additional, Vilhena, J. M., additional, Yajzey, R., additional, Zhang, W., additional, and Zimba, G., additional

Published
2023
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26. Study of excited states and observation of collective level structures in the odd–odd nucleus 194Bi

Author

Herzáň, A., Juutinen, S., Auranen, K., Grahn, T., Greenlees, P. T., Hauschild, K., Jakobsson, U., Julin, R., Ketelhut, S., Leino, M., Lopez-Martens, A., Lönnroth, T., Nieminen, P., Nyman, M., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., Slotte, J. M. K., Sorri, J., Stolze, S., and Uusitalo, J.

Published
2020
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28. In-beam γ -ray spectroscopy of 94 Ag

Author

Pereira-Lopez, X., Bentley, M. A., Wadsworth, R., Ruotsalainen, P., Lenzi, S. M., Forsberg, U., Auranen, K., Blazhev, A., Cederwall, B., Grahn, T., Greenlees, P., Illana, A., Jenkins, D. G., Julin, R., Jutila, H., Juutinen, S., Liu, X., Llewelyn, R., Luoma, M., Moschner, K., Müller-Gatermann, C., Singh, B. S. Nara, Nowacki, F., Ojala, J., Pakarinen, J., Papadakis, P., Rahkila, P., Romero, J., Sandzelius, M., Saren, J., Tann, H., Uthayakumaar, S., Uusitalo, J., Vega-Romero, J. G., Vilhena, J. M., Yajzey, R., Zhang, W., Zimba, G., and Helsinki Institute of Physics

Subjects
Coulomb energy differences, Excited-states, Proton, Decay, Ag, 114 Physical sciences, Isomer
Published
2023

29. Decay spectroscopy of Os171,172 and Ir171,172,174

Author

Zhang, W., primary, Cederwall, B., additional, Doncel, M., additional, Aktas, Ö., additional, Ertoprak, A., additional, Qi, C., additional, Grahn, T., additional, Nara Singh, B. S., additional, Cullen, D. M., additional, Hodge, D., additional, Giles, M., additional, Stolze, S., additional, Auranen, K., additional, Badran, H., additional, Braunroth, T., additional, Calverley, T., additional, Cox, D. M., additional, Fang, Y. D., additional, Greenlees, P. T., additional, Hilton, J., additional, Ideguchi, E., additional, Julin, R., additional, Juutinen, S., additional, Kumar Raju, M., additional, Leino, M., additional, Li, H., additional, Liu, H., additional, Matta, S., additional, Subramaniam, P., additional, Modamio, V., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Petrache, C. M., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Scholey, C., additional, Sorri, J., additional, Taylor, M. J., additional, Uusitalo, J., additional, and Valiente-Dobón, J. J., additional

Published
2023
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30. Nuclear Reaction Studies and Prospects for the New MARA-LEB Facility

Author

Romero, J., primary, Auranen, K., additional, Block, M., additional, Briscoe, A.D., additional, Eronen, T., additional, Gins, W., additional, Grahn, T., additional, Greenlees, P.T., additional, Illana, A., additional, Julin, R., additional, Joukainen, H., additional, Jutila, H., additional, Khuyagbaatar, J., additional, Krier, J., additional, Leino, M., additional, Louko, J., additional, Luoma, M., additional, Moore, I.D., additional, Mosat, P., additional, Ojala, J., additional, Ortiz-Cortés, A., additional, Pakarinen, J., additional, Papadakis, P., additional, Plaza, A.M., additional, Rahkila, P., additional, Raggio, A., additional, Ruotsalainen, P., additional, Sarén, J., additional, Sandzelius, M., additional, Tolosa-Delgado, A., additional, Uusitalo, J., additional, and Zimba, G., additional

Published
2023
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31. New collective structures in Au179 and their implications for the triaxial deformation of the Pt178 core

Author

Balogh, M., primary, Jajčišinová, E., additional, Venhart, M., additional, Herzáň, A., additional, Wood, J. L., additional, Joss, D. T., additional, Ali, F. A., additional, Auranen, K., additional, Bánovská, S., additional, Bírová, M., additional, Carroll, R. J., additional, Cox, D. M., additional, Cubiss, J. G., additional, Davis, T., additional, Drummond, M. C., additional, Greenlees, P. T., additional, Grahn, T., additional, Gredley, A., additional, Henderson, J., additional, Jakobsson, U., additional, Julin, R., additional, Juutinen, S., additional, Kantay, G., additional, Konki, J., additional, Konopka, P., additional, Leino, M., additional, Matoušek, V., additional, Mistry, A. K., additional, McPeake, C. G., additional, O'Donnell, D., additional, Page, R. D., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Peura, P., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Saygı, B., additional, Sedlák, M., additional, Seweryniak, D., additional, Scholey, C., additional, Sorri, J., additional, Špaček, A., additional, Stolze, S., additional, Taylor, M., additional, Thornthwaite, A., additional, Uusitalo, J., additional, Veselský, M., additional, Vielhauer, S., additional, and Wearing, F. P., additional

Published
2022
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32. Experimental observation of the M1 scissors mode in 254No

Author

Bello Garrote, F.L., primary, Lopez-Martens, A., additional, Larsen, A.C., additional, Deloncle, I., additional, Péru, S., additional, Zeiser, F., additional, Greenlees, P.T., additional, Kheswa, B.V., additional, Auranen, K., additional, Bleuel, D.L., additional, Cox, D.M., additional, Crespo Campo, L., additional, Giacoppo, F., additional, Görgen, A., additional, Grahn, T., additional, Guttormsen, M., additional, Hagen, T.W., additional, Harkness-Brennan, L., additional, Hauschild, K., additional, Henning, G., additional, Herzberg, R.-D., additional, Julin, R., additional, Juutinen, S., additional, Laplace, T.A., additional, Leino, M., additional, Midtbø, J.E., additional, Modamio, V., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Renstrøm, T., additional, Rezynkina, K., additional, Sandzelius, M., additional, Sarén, J., additional, Scholey, C., additional, Siem, S., additional, Sorri, J., additional, Stolze, S., additional, and Uusitalo, J., additional

Published
2022
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34. In-beam γ-ray spectroscopy of 94Ag

Author

Pereira-López, X., Bentley, M. A., Wadsworth, R., Ruotsalainen, P., Lenzi, S. M., Forsberg, U., Auranen, K., Blazhev, A., Cederwall, B., Grahn, T., Greenlees, P., Illana, A., Jenkins, D. G., Julin, R., Jutila, H., Juutinen, S., Liu, X., Llewelyn, R., Luoma, M., Moschner, K., Müller-Gatermann, C., Nara Singh, B. S., Nowacki, F., Ojala, J., Pakarinen, J., Papadakis, P., Rahkila, P., Romero, J., Sandzelius, M., Sarén, J., Tann, H., Uthayakumaar, S., Uusitalo, J., Vega-Romero, J. G., Vilhena, J. M., Yajzey, R., Zhang, W., and Zimba, G.

Subjects
spektroskopia, hopea, ydinfysiikka
Abstract

A recoil-beta-tagging experiment has been per formed to study the excited T = 0 and T = 1 states in the odd–odd N = Z nucleus 94Ag, populated via the 40Ca(58Ni,1p3n)94Ag reaction. The experiment was con ducted using the MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä. Through correlating fast, high-energy beta decays at the MARA focal plane with prompt γ rays emitted at the reaction target, a number of transitions between excited states in 94Ag have been identified. The timing characteris tics of these transitions confirm that they fall within decay sequences that feed the short-lived T = 1 ground state of 94Ag. The transitions are proposed to proceed within and between the sets of states with T = 0 and T = 1. Possi ble correspondence between some of these transitions from analog states in 94Pd has been discussed, and shell-model cal culations including multipole and monopole electromagnetic effects have been presented, in order to enable predictions of the decay patterns between the T = 0 and T = 1 states and to allow a theoretical set of Coulomb energy differences to be calculated for the A = 94 T = 1 analog states. peerReviewed

Published
2023

35. Decay spectroscopy of 171,172Os and 171,172,174Ir

Author

Zhang, W., Cederwall, B., Doncel, M., Aktas, Ö., Ertoprak, A., Qi, C., Grahn, T., Nara Singh, B. S., Cullen, D. M., Hodge, D., Giles, M., Stolze, S., Auranen, K., Badran, H., Braunroth, T., Calverley, T., Cox, D. M., Fang, Y. D., Greenlees, P. T., Hilton, J., Ideguchi, E., Julin, R., Juutinen, S., Kumar Raju, M., Leino, M., Li, H., Liu, H., Matta, S., Subramaniam, P., Modamio, V., Pakarinen, J., Papadakis, P., Partanen, J., Petrache, C. M., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., Sorri, J., Taylor, M. J., Uusitalo, J., and Valiente-Dobón, J. J.

Subjects
spektroskopia, ydinfysiikka
Abstract

We report on a study of the α-decay fine structure and the associated Eα−Eγ correlations in the decays of 171,172Os and 171,172,174Ir. In total, 13 new α-decay energy lines have been resolved, and three new γ-ray transitions have been observed following the new decay branches to 168Re and 167W. The weak α-decay branch from the bandhead of the νi13/2 band in 171Os observed in this work highlights an unusual competition between α, β, and electromagnetic decays from this isomeric state. The nucleus 171Os is therefore one of few nuclei observed to exhibit three different decay modes from the same excited state. The nuclei of interest were produced in 92Mo(83Kr,xpyn) fusion-evaporation reactions at the Accelerator Laboratory of the University of Jyväskylä, Finland. The fusion products were selected using the gas-filled ion separator RITU and their decays were characterized using an array of detectors for charged particles and electromagnetic radiation known as GREAT. Prompt γ-ray transitions were detected and correlated with the decays using the JUROGAM II germanium detector array surrounding the target position. Results obtained from total Routhian surface (TRS) calculations suggest that α-decay fine structure and the associated hindrance factors may be a sensitive probe of even relatively small shape changes between the final states in the daughter nucleus. peerReviewed

Published
2023

36. Nuclear rotation at the fission limit in <math><mmultiscripts><mi>Rf</mi><mprescripts/><none/><mn>254</mn></mmultiscripts></math>

Author

Seweryniak, D, Huang, T, Auranen, K, Ayangeakaa, A.D, Back, B.B, Carpenter, M.P, Chowdhury, P, Clark, R.M, Copp, P.A, Favier, Z, Hauschild, K, He, X.-T, Khoo, T.L, Kondev, F.G, Korichi, A, Lauritsen, T, Li, J, Morse, C, Potterveld, D.H, Savard, G, Stolze, S, Wu, J, Zhang, J, Xu, Y.-F, Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]
Abstract

International audience; A ground-state rotational band in the fissile nucleus Rf254 was observed for the first time. Levels up to spin 14ℏ and excitation energy of 1.56 MeV were observed. The Rf254 nuclei were produced using the Pb206(Ti50,2n) fusion-evaporation reaction. It is the weakest reaction channel ever studied using in-beam γ-ray spectroscopic methods. The reaction products were separated from the beam in the Argonne gas-filled analyzer (AGFA). The Rf254 nuclei were implanted into a double-sided Si strip detector at the AGFA focal plane and tagged with subsequent ground-state spontaneous fission decays using temporal and spatial correlations. Prompt γ rays in coincidence with the Rf254 recoils were detected in the Gammasphere array of Ge detectors. In order to identify the ground-state rotational band in Rf254, a method for identifying rotational bands in low statistics γ-ray spectra was developed. The deduced Rf254 kinematic moment of inertia is smaller compared to neighboring even-even nuclei. This is most likely associated with a slightly lower quadrupole deformation and stronger pairing correlations in Rf254. The behavior of the moment of inertia as a function of rotational frequency is similar to that of the lighter N=150 isotones Fm250 and No252.

Published
2023

37. In-beam study of 253No using the SAGE spectrometer

Author

Mistry, A. K., Herzberg, R. -D., Greenlees, P. T., Papadakis, P., Auranen, K., Butler, P. A., Cox, D. M., Garnsworthy, A. B., Grahn, T., Hauschild, K., Jakobsson, U., Joss, D. T., Julin, R., Ketelhut, S., Konki, J., Leino, M., Lopez-Martens, A., Page, R. D., Pakarinen, J., Peura, P., Rahkila, P., Sandzelius, M., Scholey, C., Simpson, J., Seddon, D., Sorri, J., Stolze, S., Thornhill, J., Uusitalo, J., and Wells, D.

Published
2017
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38. Experimental observation of the 1 Scissors Mode in No

Author

Bello Garrote, F.L., Lopez-Martens, A., Larsen, A.C., Deloncle, I., Péru, S., Zeiser, F., Greenlees, P.T., Kheswa, B.V., Auranen, K., Bleuel, D.L., Cox, D.M., Crespo Campo, L., Giacoppo, F., Görgen, A., Grahn, T., Guttormsen, M., Hagen, T.W., Harkness-Brennan, L., Hauschild, K., Henning, G., Herzberg, R.D., Julin, R., Juutinen, S., Laplace, T.A., Leino, M., Midtbø, J.E., Modamio, V., Pakarinen, J., Papadakis, P., Partanen, J., Renstrøm, T., Rezynkina, K., Sandzelius, M., Sarén, J., Scholey, C., Siem, S., Sorri, J., Stolze, S., and Uusitalo, J.

Abstract

We present the first experimental evidence of the scissors mode in the superheavy nucleus $^{254}$No produced in the $^{208}$Pb($^{48}$Ca, 2nγ))$^{254}$No reaction. The spectrum of γ rays emitted by the excited $^{254}$No nuclei shows an enhanced γ-ray yield for transition energies of ≈2.5 MeV. By measuring the linear polarization properties of the emitted γ rays, we confirm that the transitions in the enhancement region are predominantly of magnetic-dipole character, characteristic for the scissors mode. To further characterize the enhanced γ-ray yield, simulations of the electromagnetic decay of $^{254}$No were performed. The observed enhancement is reproduced by including an M1 component in the γ strength function with total strength B(M1↑)=11.8(19)μN2. This is in good agreement with the integrated M1 strength from sum-rule estimates and new calculations within the quasi-particle random-phase approximation presented here. Our results provide a stringent test of phenomenological formulae for the scissors mode currently used in stellar nucleosynthesis calculations. We find that those formulae are not satisfactory, and we recommend using sum-rule estimates assuming a rigid-body moment of inertia instead for describing the scissors mode in superheavy nuclei.

Published
2022

39. Collective 2+ 1 excitations in 206Po and 208,210Rn

Author

Grahn, T., Pakarinen, J., Jokiniemi, L., Albers, M., Auranen, K., Bauer, C., Bernards, C., Blazhev, A., Butler, P. A., Bönig, S., Damyanova, A., De Coster, T., De Witte, H., Elseviers, J., Gaffney, L. P., Huyse, M., Herzáň, A., Jakobsson, U., Julin, R., Kesteloot, N., Konki, J., Kröll, Th., Lewandowski, L., Moschner, K., Peura, P., Pfeiffer, M., Radeck, D., Rahkila, P., Rapisarda, E., Reiter, P., Reynders, K., Rudiger, M., Salsac, M. -D., Sambi, S., Scheck, M., Seidlitz, M., Siebeck, B., Steinbach, T., Stolze, S., Suhonen, J., Thoele, P., Thürauf, M., Warr, N., Van Duppen, P., Venhart, M., Vermeulen, M. J., Werner, V., Veselsky, M., Vogt, A., Wrzosek-Lipska, K., and Zielińska, M.

Published
2016
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41. Nanosecond-Scale Proton Emission from Strongly Oblate-Deformed Lu-149

Author

Auranen, K, Briscoe, AD, Ferreira, LS, Grahn, T, Greenlees, PT, Herzan, A, Illana, A, Joss, DT, Joukainen, H, Julin, R, Jutila, H, Leino, M, Louko, J, Luoma, M, Maglione, E, Ojala, J, Page, RD, Pakarinen, J, Rahkila, P, Romero, J, Ruotsalainen, P, Sandzelius, M, Saren, J, Tolosa-Delgado, A, Uusitalo, J, and Zimba, G

Published
2022

42. Single-particle states and parity doublets in odd-Z Ac-221 and Pa-225 from alpha-decay spectroscopy

Author

Parr, E, Smith, JF, Greenlees, PT, Butler, PA, Auranen, K, Chapman, R, Cox, DM, Cullen, DM, Gaffney, LP, Grahn, T, Gregor, ET, Grocutt, L, Herzan, A, Herzberg, R-D, Hodge, D, Jakobsson, U, Julin, R, Juutinen, S, Keatings, JM, Konki, J, Leino, M, McKee, PP, McPeake, C, Mengoni, D, Mistry, AK, Singh, BS Nara, O'Neill, GG, Pakarinen, J, Papadakis, P, Partanen, J, Peura, P, Rahkila, P, Ruotsalainen, P, Sandzelius, M, Saren, J, Scheck, M, Scholey, C, Siciliano, M, Smolen, M, Sorri, J, Spagnoletti, P, Spohr, KM, Stolze, S, Taylor, MJ, and Uusitalo, J

Published
2022

43. Masses and Beta-decay Studies of Neutron-rich Nuclei using the X-array and Gammasphere

Author

Kondev F.G., Hartley D.J., Orford R., Clark J.A, Savard G., Auranen K., Ayangeakaa A.D., Bottoni S., Carpenter M.P., Copp P., Hicks K., Hoffman C.R., Janssens R.V.F., Kay B.P., Lauritsen T., Li T., Marley S.T., Morgan G.E., Mukherjee G., Nandi S., Reviol W., Sethi J., Seweryniak D., Stolze S., Wu J., Yadav R., and Zhu S.

Subjects
Physics, QC1-999
Abstract

Properties of neutron-rich nuclei in the A˜160 region are important for achieving a better understanding of the nuclear structure in this region where little is known owing to diffculties in the production of these nuclei at the present nuclear physics facilities. These properties are essential ingredients in the interpretation of the rareearth peak at A˜160 in the r process abundance distribution, since theoretical models are sensitive to nuclear structure input. Predicated on these ideas, we have initiated a new experimental program at Argonne National Laboratory. During the first experiment, beams from the Californium Rare Isotope Breeder Upgrade radioactive beam facility were used in conjunction with the SATURN decay station and the X-array. We focused initially on several odd-odd nuclei, where β decays of both the ground state and an excited isomer were investigated. Because of the spin difference, a variety of structures in the daughter nuclei were selectively populated and characterized based on their decay properties. Mass measurements using the Canadian Penning Trap aimed at establishing the excitation energy of the β-decaying isomers were also carried out. Evidence was found for a change in the single-particle structure, which in turn results in the formation of a sizable N=98 sub-shell gap at large deformation. Results from the first experimental campaign using the newly-commissioned β-decay station at Gammasphere are also presented.

Published
2019
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44. First direct measurement of the N13(α,p)O16 reaction relevant for core-collapse supernovae nucleosynthesis

Author

Jayatissa, H., primary, Avila, M. L., additional, Rehm, K. E., additional, Talwar, R., additional, Mohr, P., additional, Auranen, K., additional, Chen, J., additional, Gorelov, D. A., additional, Hoffman, C. R., additional, Jiang, C. L., additional, Kay, B. P., additional, Kuvin, S. A., additional, and Santiago-Gonzalez, D., additional

Published
2022
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45. Nanosecond-Scale Proton Emission from Strongly Oblate-Deformed Lu149

Author

Auranen, K., primary, Briscoe, A. D., additional, Ferreira, L. S., additional, Grahn, T., additional, Greenlees, P. T., additional, Herzáň, A., additional, Illana, A., additional, Joss, D. T., additional, Joukainen, H., additional, Julin, R., additional, Jutila, H., additional, Leino, M., additional, Louko, J., additional, Luoma, M., additional, Maglione, E., additional, Ojala, J., additional, Page, R. D., additional, Pakarinen, J., additional, Rahkila, P., additional, Romero, J., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Tolosa-Delgado, A., additional, Uusitalo, J., additional, and Zimba, G., additional

Published
2022
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46. Single-particle states and parity doublets in odd- Z Ac221 and Pa225 from α -decay spectroscopy

Author

Parr, E., primary, Smith, J. F., additional, Greenlees, P. T., additional, Butler, P. A., additional, Auranen, K., additional, Chapman, R., additional, Cox, D. M., additional, Cullen, D. M., additional, Gaffney, L. P., additional, Grahn, T., additional, Gregor, E. T., additional, Grocutt, L., additional, Herzáň, A., additional, Herzberg, R.-D., additional, Hodge, D., additional, Jakobsson, U., additional, Julin, R., additional, Juutinen, S., additional, Keatings, J. M., additional, Konki, J., additional, Leino, M., additional, McKee, P. P., additional, McPeake, C., additional, Mengoni, D., additional, Mistry, A. K., additional, Singh, B. S. Nara, additional, O'Neill, G. G., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Peura, P., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Scheck, M., additional, Scholey, C., additional, Siciliano, M., additional, Smolen, M., additional, Sorri, J., additional, Spagnoletti, P., additional, Spohr, K. M., additional, Stolze, S., additional, Taylor, M. J., additional, and Uusitalo, J., additional

Published
2022
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48. νi13/2 structures in 155Sm and 159Gd: Supporting evidence of a Z=60 deformed subshell gap

Author

Hartley, D.J., Kondev, F.G., Janssens, R.V.F., Carpenter, M.P., Little, D., Lauritsen, T., Hoffman, C.R., Heery, J., Savard, G., Simpson, J., Auranen, K., Clark, J.A., Boston, A.J., Wilson, G.L., Stolze, S., Villafana, K., Riley, M.A., Li, J., Greene, J.P., Seweryniak, D., Paul, E.S., Zhu, S., Ayangeakaa, A.D., Baron, J.S., and Wu, J.

Abstract

Maximal ground-state deformation should occur when both proton and neutron Fermi surfaces are located at midshell. However, subshell gaps that stabilize large deformation can exist at proton or neutron values other than midshell. One such gap may occur at Z=60 in the rare-earth region, as the energy of the first 2+ states in even-even nuclei are often lowest in an isotonic chain for neodymium (Z=60) rather than the midshell isotopes of dysprosium (Z=66). Further evidence of this deformed gap has now been observed by investigating the signature splitting systematics of the νi13/2 bands found in the odd-N, rare-earth nuclei. These were aided by the present observation of the νi13/2 band in Gd159 and the confirmation of the same structure in Sm155 via the transfer of a neutron from a Gd160 beam to a Sm154 target.

Published
2022
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49. Single-particle states and parity doublets in odd- Z Ac 221 and Pa 225 from α -decay spectroscopy

Author

Parr, E., Smith, J. F., Greenlees, P. T., Butler, P. A., Auranen, K., Chapman, R., Cox, D. M., Cullen, D. M., Gaffney, L. P., Grahn, T., Gregor, E. T., Grocutt, L., Herzan, A., Herzberg, R. -D., Hodge, D., Jakobsson, U., Julin, R., Juutinen, S., Keatings, J. M., Konki, J., Leino, M., Mckee, P. P., Mcpeake, C., Mengoni, D., Mistry, A. K., Singh, B. S. N., O'Neill, G. G., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Saren, J., Scheck, M., Scholey, C., Siciliano, M., Smolen, M., Sorri, J., Spagnoletti, P., Spohr, K. M., Stolze, S., Taylor, M. J., and Uusitalo, J.

Published
2022

50. Single-particle states and parity doublets in odd-Z 221Ac and 225Pa from α-decay spectroscopy

Author

Parr, E., Smith, J. F., Greenlees, P. T., Butler, P. A., Auranen, K., Chapman, R., Cox, D. M., Cullen, D. M., Gaffney, L. P., Grahn, T., Gregor, E. T., Grocutt, L., Herzáň, A., Herzberg, R.-D., Hodge, D., Jakobsson, U., Julin, R., Juutinen, S., Keatings, J. M., Konki, J., Leino, M., McKee, P. P., McPeake, C., Mengoni, D., Mistry, A. K., Nara Singh, B. S., O'Neill, G. G., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scheck, M., Scholey, C., Siciliano, M., Smolen, M., Sorri, J., Spagnoletti, P., Spohr, K. M., Stolze, S., Taylor, M. J., and Uusitalo, J.

Subjects
ydinfysiikka
Abstract

Low-lying states in the odd-Z isotopes 22189Ac132 and 22591Pa134 have been studied using α-particle and αγ-coincidence spectroscopy in the 225Pa→221Ac→217Fr decay chain. Ground-state spin and parity assignments of Iπ = 5/2− are proposed for both 221Ac and 225Pa, with the odd proton occupying the Ω = 5/2 orbital of the quadrupole-octupole deformed shell model in both nuclei. In 221Ac, excited states in the bands based on the Ω = 5/2 and Ω = 3/2 orbitals have been identified, including proposed parity-doublet states. The results suggest that reflection-asymmetric deformation of the ground state persists in the odd-A members of the isotope chains down to N = 132 for Ac and N = 134 for Pa, before reaching the transitional region at N = 130. peerReviewed

Published
2022

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