Author: "Nefkens BM" - Searchworks@Jio Institute Digital Library Search Results

1. Measurements of double-polarized compton scattering asymmetries and extraction of the proton spin polarizabilities.

Author: Martel PP, Miskimen R, Aguar-Bartolome P, Ahrens J, Akondi CS, Annand JR, Arends HJ, Barnes W, Beck R, Bernstein A, Borisov N, Braghieri A, Briscoe WJ, Cherepnya S, Collicott C, Costanza S, Denig A, Dieterle M, Downie EJ, Fil'kov LV, Garni S, Glazier DI, Gradl W, Gurevich G, Hall Barrientos P, Hamilton D, Hornidge D, Howdle D, Huber GM, Jude TC, Kaeser A, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Krusche B, Lazarev A, Lisin V, Livingston K, MacGregor IJ, Mancell J, Manley DM, Meyer W, Middleton DG, Mushkarenkov A, Nefkens BM, Neganov A, Nikolaev A, Oberle M, Ortega Spina H, Ostrick M, Ott P, Otte PB, Oussena B, Pedroni P, Polonski A, Polyansky V, Prakhov S, Rajabi A, Reicherz G, Rostomyan T, Sarty A, Schrauf S, Schumann S, Sikora MH, Starostin A, Steffen O, Strakovsky II, Strub T, Supek I, Thiel M, Tiator L, Thomas A, Unverzagt M, Usov Y, Watts DP, Witthauer L, Werthmüller D, and Wolfes M
Abstract: The spin polarizabilities of the nucleon describe how the spin of the nucleon responds to an incident polarized photon. The most model-independent way to extract the nucleon spin polarizabilities is through polarized Compton scattering. Double-polarized Compton scattering asymmetries on the proton were measured in the Δ(1232) region using circularly polarized incident photons and a transversely polarized proton target at the Mainz Microtron. Fits to asymmetry data were performed using a dispersion model calculation and a baryon chiral perturbation theory calculation, and a separation of all four proton spin polarizabilities in the multipole basis was achieved. The analysis based on a dispersion model calculation yields γ(E1E1)=-3.5±1.2, γ(M1M1)=3.16±0.85, γ(E1M2)=-0.7±1.2, and γ(M1E2)=1.99±0.29, in units of 10(-4) fm(4).
Published: 2015
Full Text: View/download PDF

2. Measurement of the transverse target and beam-target asymmetries in η meson photoproduction at MAMI.

Author: Akondi CS, Annand JR, Arends HJ, Beck R, Bernstein A, Borisov N, Braghieri A, Briscoe WJ, Cherepnya S, Collicott C, Costanza S, Downie EJ, Dieterle M, Fix A, Fil'kov LV, Garni S, Glazier DI, Gradl W, Gurevich G, Hall Barrientos P, Hamilton D, Hornidge D, Howdle D, Huber GM, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Krusche B, Lazarev A, Lisin V, Livingston K, MacGregor IJ, Mancel J, Manley DM, Martel P, McNicoll EF, Meyer W, Middleton D, Miskimen R, Mushkarenkov A, Nefkens BM, Neganov A, Nikolaev A, Oberle M, Ostrick M, Ortega H, Ott P, Otte PB, Oussena B, Pedroni P, Polonski A, Polyanski VV, Prakhov S, Reicherz G, Rostomyan T, Sarty A, Schumann S, Steffen O, Strakovsky II, Strub T, Supek I, Tiator L, Thomas A, Unverzagt M, Usov YA, Watts DP, Werthmüller D, Witthauer L, and Wolfes M
Abstract: We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the γ[over →]p[over →]→ηp reaction up to a center-of-mass energy of W=1.9 GeV. The data were obtained with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility of the Mainz Microtron MAMI. All existing model predictions fail to reproduce the new data indicating a significant impact on our understanding of the underlying dynamics of η meson photoproduction. The peculiar nodal structure observed in existing T data close to threshold is not confirmed.
Published: 2014
Full Text: View/download PDF

3. Neutron skin of (208)pb from coherent pion photoproduction.

Author: Tarbert CM, Watts DP, Glazier DI, Aguar P, Ahrens J, Annand JR, Arends HJ, Beck R, Bekrenev V, Boillat B, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling R, Downie EJ, Foehl K, Grabmayr P, Gregor R, Heid E, Hornidge D, Jahn O, Kashevarov VL, Knezevic A, Kondratiev R, Korolija M, Kotulla M, Krambrich D, Krusche B, Lang M, Lisin V, Livingston K, Lugert S, MacGregor IJ, Manley DM, Martinez M, McGeorge JC, Mekterovic D, Metag V, Nefkens BM, Nikolaev A, Novotny R, Owens RO, Pedroni P, Polonski A, Prakhov SN, Price JW, Rosner G, Rost M, Rostomyan T, Schadmand S, Schumann S, Sober D, Starostin A, Supek I, Thomas A, Unverzagt M, Walcher T, Zana L, and Zehr F
Abstract: Information on the size and shape of the neutron skin on (208)Pb is extracted from coherent pion photoproduction cross sections measured using the Crystal Ball detector together with the Glasgow tagger at the MAMI electron beam facility. On exploitation of an interpolated fit of a theoretical model to the measured cross sections, the half-height radius and diffuseness of the neutron distribution are found to be c(n)=6.70±0.03(stat.) fm and a(n)=0.55±0.01(stat.)(-0.03)(+0.02)(sys.) fm, respectively, corresponding to a neutron skin thickness Δr(np)=0.15±0.03(stat.)(-0.03)(+0.01)(sys.) fm. The results give the first successful extraction of a neutron skin thickness with an electromagnetic probe and indicate that the skin of (208)Pb has a halo character. The measurement provides valuable new constraints on both the structure of nuclei and the equation of state for neutron-rich matter.
Published: 2014
Full Text: View/download PDF

4. Photoproduction of π0 mesons off neutrons in the nucleon resonance region.

Author: Dieterle M, Keshelashvili I, Ahrens J, Annand JR, Arends HJ, Bantawa K, Bartolome PA, Beck R, Bekrenev V, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Demissie B, Downie EJ, Drexler P, Fil'kov LV, Fix A, Glazier DI, Hamilton D, Heid E, Hornidge D, Howdle D, Huber GM, Jaegle I, Jahn O, Jude TC, Käser A, Kashevarov VL, Kondratiev R, Korolija M, Kruglov SP, Krusche B, Kulbardis A, Lisin V, Livingston K, MacGregor IJ, Maghrbi Y, Mancell J, Manley DM, Marinides Z, Martinez M, McGeorge JC, McNicoll E, Mekterovic D, Metag V, Micanovic S, Middleton DG, Mushkarenkov A, Nefkens BM, Nikolaev A, Novotny R, Oberle M, Ostrick M, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov SN, Robinson J, Rosner G, Rostomyan T, Schumann S, Sikora MH, Sober D, Starostin A, Supek I, Thiel M, Thomas A, Unverzagt M, Watts DP, Werthmüller D, and Witthauer L
Abstract: Precise angular distributions have been measured for the first time for the photoproduction of π0 mesons off neutrons bound in the deuteron. The effects from nuclear Fermi motion have been eliminated by a complete kinematic reconstruction of the final state. The influence of final-state-interaction effects has been estimated by a comparison of the reaction cross section for quasifree protons bound in the deuteron to the results for free protons and then applied as a correction to the quasifree neutron data. The experiment was performed at the tagged photon facility of the Mainz Microtron MAMI with the Crystal Ball and TAPS detector setup for incident photon energies between 0.45 and 1.4 GeV. The results are compared to the predictions from reaction models and partial-wave analyses based on data from other isospin channels. The model predictions show large discrepancies among each other and the present data will provide much tighter constraints. This is demonstrated by the results of a new analysis in the framework of the Bonn-Gatchina coupled-channel analysis which included the present data.
Published: 2014
Full Text: View/download PDF

5. Measurement of the 1H(γ, p)π0 reaction using a novel nucleon spin polarimeter.

Author: Sikora MH, Watts DP, Glazier DI, Aguar-Bartolomé P, Akasoy LK, Annand JR, Arends HJ, Bantawa K, Beck R, Bekrenev VS, Berghäuser H, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling RF, Demissie BT, Downie EJ, Drexler P, Fil'kov LV, Freehart B, Gregor R, Hamilton D, Heid E, Hornidge D, Howdle DA, Jaegle I, Jahn O, Jude TC, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Kotulla M, Koulbardis AA, Kruglov SP, Krusche B, Lisin V, Livingston K, MacGregor IJ, Maghrbi Y, Manley DM, Marinides Z, Martinez M, McGeorge JC, McKinnon B, McNicoll EF, Mekterovic D, Metag V, Micanovic S, Middleton DG, Mushkarenkov A, Nefkens BM, Nikolaev A, Novotny R, Ostrick M, Otte PB, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov S, Robinson J, Rosner G, Rostomyan T, Schumann S, Sober DI, Starostin A, Strakovsky II, Suarez IM, Supek I, Thiel M, Thomas A, Unverzagt M, Werthmüller D, Workman RL, Zamboni I, and Zehr F
Abstract: We report the first large-acceptance measurement of polarization transfer from a polarized photon beam to a recoiling nucleon. The measurement pioneers a novel polarimetry technique, which can be applied to many other nuclear and hadron physics experiments. The commissioning reaction of 1H(γ, p)π0 in the range 0.4
Published: 2014
Full Text: View/download PDF

6. Narrow structure in the excitation function of η photoproduction off the neutron.

Author: Werthmüller D, Witthauer L, Keshelashvili I, Aguar-Bartolomé P, Ahrens J, Annand JR, Arends HJ, Bantawa K, Beck R, Bekrenev V, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Demissie B, Dieterle M, Downie EJ, Drexler P, Fil'kov LV, Fix A, Glazier DI, Hamilton D, Heid E, Hornidge D, Howdle D, Huber GM, Jaegle I, Jahn O, Jude TC, Käser A, Kashevarov VL, Kondratiev R, Korolija M, Kruglov SP, Krusche B, Kulbardis A, Lisin V, Livingston K, MacGregor IJ, Maghrbi Y, Mancell J, Manley DM, Marinides Z, Martinez M, McGeorge JC, McNicoll EF, Metag V, Middleton DG, Mushkarenkov A, Nefkens BM, Nikolaev A, Novotny R, Oberle M, Ostrick M, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov SN, Robinson J, Rosner G, Rostomyan T, Schumann S, Sikora MH, Sober D, Starostin A, Supek I, Thiel M, Thomas A, Unverzagt M, and Watts DP
Abstract: The photoproduction of η mesons off nucleons bound in 2H and 3He has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the η→2γ and η→3π0 decays and the recoil nucleons were detected with an almost 4π electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of γn→nη. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W=(1670±5) MeV and Γ=(30±15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.
Published: 2013
Full Text: View/download PDF

7. Accurate test of chiral dynamics in the γp→π0p reaction.

Author: Hornidge D, Aguar Bartolomé P, Annand JR, Arends HJ, Beck R, Bekrenev V, Berghäuser H, Bernstein AM, Braghieri A, Briscoe WJ, Cherepnya S, Dieterle M, Downie EJ, Drexler P, Fernández-Ramírez C, Filkov LV, Glazier DI, Hall Barrientos P, Heid E, Hilt M, Jaegle I, Jahn O, Jude TC, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Koulbardis A, Krambrich D, Kruglov S, Krusche B, Laffoley AT, Lisin V, Livingston K, MacGregor IJ, Mancell J, Manley DM, McNicoll EF, Mekterovic D, Metag V, Micanovic S, Middleton DG, Moores KW, Mushkarenkov A, Nefkens BM, Oberle M, Ostrick M, Otte PB, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov S, Robinson J, Rostomyan T, Scherer S, Schumann S, Sikora MH, Starostin A, Supek I, Thiel M, Thomas A, Tiator L, Unverzagt M, Watts DP, Werthmüller D, and Witthauer L
Abstract: A precision measurement of the differential cross sections dσ/dΩ and the linearly polarized photon asymmetry Σ≡(dσ⊥-dσ∥)/(dσ⊥+dσ∥) for the γp→π0p reaction in the near-threshold region has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The Glasgow-Mainz photon tagging facility along with the Crystal Ball/TAPS multiphoton detector system and a cryogenic liquid hydrogen target were used. These data allowed for a precise determination of the energy dependence of the real parts of the S- and all three P-wave amplitudes for the first time and provide the most stringent test to date of the predictions of chiral perturbation theory and its energy region of agreement with experiment.
Published: 2013
Full Text: View/download PDF

8. Beam-helicity asymmetries in double-pion photoproduction off the proton.

Author: Krambrich D, Zehr F, Fix A, Roca L, Aguar P, Ahrens J, Annand JR, Arends HJ, Beck R, Bekrenev V, Boillat B, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling R, Downie EJ, Dexler P, Glazier DI, Grabmayr P, Gregor R, Heid E, Hornidge D, Jahn O, Kashevarov VL, Knezevic A, Kondratiev R, Korolija M, Kotulla M, Krusche B, Kulbardis A, Lang M, Lisin V, Livingston K, Lugert S, MacGregor IJ, Manley DM, Martinez M, McGeorge JC, Mekterovic D, Metag V, Nefkens BM, Nikolaev A, Pedroni P, Pheron F, Polonski A, Prakhov SN, Price JW, Rosner G, Rost M, Rostomyan T, Schumann S, Sober D, Starostin A, Supek I, Tarbert CM, Thomas A, Unverzagt M, Walcher T, and Watts DP
Abstract: Beam-helicity asymmetries have been measured at the MAMI accelerator in Mainz in the three isospin channels gamma[over -->]p-->pi(+)pi(0)n, gamma[over -->]p-->pi(0)pi(0)p, and gamma[over -->]p-->pi(+)pi(-)p. The circularly polarized photons, produced from bremsstrahlung of longitudinally polarized electrons, were tagged with the Glasgow magnetic spectrometer. Charged pions and the decay photons of pi(0) mesons were detected in a 4pi electromagnetic calorimeter which combined the Crystal Ball detector with the TAPS detector. The precisely measured asymmetries are very sensitive to details of the production processes and are thus key observables in the modeling of the reaction dynamics.
Published: 2009
Full Text: View/download PDF

9. Incoherent neutral pion photoproduction on 12C.

Author: Tarbert CM, Watts DP, Aguar P, Ahrens J, Annand JR, Arends HJ, Beck R, Bekrenev V, Boillat B, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling R, Downie EJ, Föhl K, Glazier DI, Grabmayr P, Gregor R, Heid E, Hornidge D, Jahn O, Kashevarov VL, Knezevic A, Kondratiev R, Korolija M, Kotulla M, Krambrich D, Krusche B, Lang M, Lisin V, Livingston K, Lugert S, Macgregor IJ, Manley DM, Martinez M, McGeorge JC, Mekterovic D, Metag V, Nefkens BM, Nikolaev A, Novotny R, Owens RO, Pedroni P, Polonski A, Prakhov SN, Price JW, Rosner G, Rost M, Rostomyan T, Schadmand S, Schumann S, Sober D, Starostin A, Supek I, Thomas A, Unverzagt M, Walcher T, and Zehr F
Abstract: We present the first detailed measurement of incoherent photoproduction of neutral pions to a discrete state of a residual nucleus. The 12C(gamma,pi(0))(12)C*(4.4 MeV) reaction has been studied with the Glasgow photon tagger at MAMI employing a new technique which uses the large solid angle Crystal Ball detector both as a pi(0) spectrometer and to detect decay photons from the excited residual nucleus. The technique has potential applications to a broad range of future nuclear measurements with the Crystal Ball and similar detector systems elsewhere. Such data are sensitive to the propagation of the Delta in the nuclear medium and will give the first information on matter transition form factors from measurements with an electromagnetic probe. The incoherent cross sections are compared to two theoretical predictions including a Delta-hole model.
Published: 2008
Full Text: View/download PDF

10. Test of charge conjugation invariance.

Author: Nefkens BM, Prakhov S, Gårdestig A, Allgower CE, Bekrenev V, Briscoe WJ, Clajus M, Comfort JR, Craig K, Grosnick D, Isenhower D, Knecht N, Koetke D, Koulbardis A, Kozlenko N, Kruglov S, Lolos G, Lopatin I, Manley DM, Manweiler R, Marusić A, McDonald S, Olmsted J, Papandreou Z, Peaslee D, Phaisangittisakul N, Price JW, Ramirez AF, Sadler M, Shafi A, Spinka H, Stanislaus TD, Starostin A, Staudenmaier HM, Supek I, and Tippens WB
Abstract: We report on the first determination of upper limits on the branching ratio (BR) of eta decay to pi0pi0gamma and to pi0pi0pi0gamma. Both decay modes are strictly forbidden by charge conjugation (C) invariance. Using the Crystal Ball multiphoton detector, we obtained BR(eta-->pi0pi0gamma)<5 x 10(-4) at the 90% confidence level, in support of C invariance of isoscalar electromagnetic interactions of the light quarks. We have also measured BR(eta-->pi0pi0pi0gamma)<6 x 10(-5) at the 90% confidence level, in support of C invariance of isovector electromagnetic interactions.
Published: 2005
Full Text: View/download PDF

11. Dynamics of the pi(-)p-->pi(0)pi(0)n reaction for p(pi(-))<750 MeV/c.

Author: Craig K, Comfort JR, Allgower CE, Bekrenev V, Berger E, Briscoe WJ, Clajus M, Draper B, Grosnick D, Isenhower D, Knecht N, Koetke D, Koulbardis A, Kozlenko N, Kruglov S, Lolos GJ, Lopatin I, Manley DM, Manweiler R, Marusić A, McDonald S, Nefkens BM, Olmsted J, Papandreou Z, Peaslee D, Phaisangittisakul N, Prakhov S, Price JW, Pulver M, Ramirez AF, Sadler ME, Shafi A, Spinka H, Stanislaus S, Starostin A, Supek I, Staudenmaier HM, and Tippens WB
Abstract: Data are presented for the reaction pi(-)p-->pi(0)pi(0)n in the range from threshold to p(pi(-))=750 MeV/c. The systematics of the data and multipole analyses are examined for sensitivity to a f(0)(600) ("sigma") meson. A one-pion-exchange mechanism is found to be very weak, or absent. The reaction appears to become dominated by sequential pi(0) decays through the Delta(1232) resonance as the beam momentum increases, along with substantial interference effects from several competing mechanisms.
Published: 2003
Full Text: View/download PDF

12. Properties of the Lambda(1670)(1-)/2 resonance.

Author: Manley DM, Abaev VV, Allgower CE, Bekrenev V, Briscoe WJ, Clajus M, Comfort JR, Craig K, Grosnick D, Isenhower D, Knecht N, Koetke DD, Kulbardis AA, Kozlenko NG, Kruglov S, Lolos G, Lopatin IV, Manweiler R, Marusić A, McDonald S, Nefkens BM, Olmsted J, Papandreou Z, Peaslee DC, Phaisangittisakul N, Prakhov S, Price JW, Ramirez AF, Sadler M, Shafi A, Spinka H, Stanislaus TD, Starostin A, Staudenmaier HM, Strakovsky II, Supek I, and Tippens WB
Abstract: Recently the Crystal Ball Collaboration measured precise new data for the near-threshold reaction K(-)p-->etaLambda, which is dominated by formation of the Lambda(1670)1 / 2(-). In this Letter, we present results of a unitary, multichannel analysis that incorporates the new Crystal Ball data. For our preferred fit, we obtain mass M = 1673+/-2 MeV, width Gamma = 23+/-6 MeV, and elasticity x = 0.37+/-0.07. This elasticity is significantly larger than previously recognized. Resonance parameters of our preferred fit are in striking agreement with the quark-model predictions of Koniuk and Isgur.
Published: 2002
Full Text: View/download PDF

13. Determination of the quadratic slope parameter in eta-->3pi(0) decay.

Author: Tippens WB, Prakhov S, Allgower CE, Bekrenev V, Berger E, Briscoe WJ, Clajus M, Comfort JR, Craig K, Efendiev A, Grosnick D, Holstein BR, Huber GM, Isenhower D, Knecht N, Koetke D, Koulbardis A, Kozlenko N, Kruglov S, Lolos GJ, Lopatin I, Manley DM, Marusić A, Manweiler R, McDonald S, Nefkens BM, Olmsted J, Papandreou Z, Phaisangittisakul N, Price JW, Pulver M, Ramirez AF, Sadler ME, Shafi A, Spinka H, Stanislaus S, Starostin A, and Staudenmaier HM
Abstract: We have determined the quadratic slope parameter alpha for eta-->3pi(0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta-->3pi(0) decays produced in the reaction pi(-)p-->n(eta) close to the eta threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations.
Published: 2001
Full Text: View/download PDF

14. Measurement of pi(0)pi(0) production in the nuclear medium by pi(-) interactions at 0.408 GeV/c.

Author: Starostin A, Staudenmaier HM, Allgower CE, Bekrenev V, Berger E, Briscoe WJ, Clajus M, Comfort JR, Craig K, Grosnick D, Isenhower D, Knecht N, Koetke D, Koulbardis A, Kozlenko N, Kruglov S, Kycia T, Lolos G, Lopatin I, Manley DM, Manweiler B, Marusić A, McDonald S, Nefkens BM, Olmsted J, Papandreou Z, Peaslee D, Peterson RJ, Phaisangittisakul N, Prakhov S, Pulver M, Ramirez AF, Sadler M, Shafi A, Slaus I, Spinka H, Stanislaus S, Supek I, and Tippens WB
Abstract: We report on an investigation of the (pi(-),pi(0)pi(0)) reaction by means of measurements of the pi(0)pi(0) invariant mass distributions from pi(-) interactions on H, D, C, Al, and Cu targets at p(pi(-)) = 0.408 GeV/c. The sharp, strong peak in the pi(+)pi(-) invariant mass near 2m(pi) reported by the CHAOS Collaboration is not seen in our pi(0)pi(0) data. However, we do observe a change in the shape of the pi(0)pi(0) invariant mass spectrum for the different targets, indicating that the pi(0)pi(0) interaction diminishes in the nuclear medium as represented by nuclei D, C, Al, and Cu, compared to hydrogen.
Published: 2000
Full Text: View/download PDF

15. Search for the CP forbidden decay eta-->4pi(0)

Author: Prakhov S, Tippens WB, Allgower C, Bekrenev V V, Berger E, Briscoe WJ, Clajus M, Comfort JR, Craig K, Grosnick D, Huber GM, Isenhower D, Knecht N, Koetke D, Koulbardis A, Kozlenko N, Kruglov S, Kycia T, Lolos GJ, Lopatin I I, Manley DM, Marusic A, Manweiler R, McDonald S, Nefkens BM, and Olmsted J
Abstract: We report the first determination of the upper limit for the branching ratio of the CP forbidden decay eta-->4pi(0). No events were observed in a sample of 3.0x10(7) eta decays. The experiment was performed with the Crystal Ball multiphoton spectrometer installed in a separated pi(-) beam at the AGS (Alternating Gradient Synchrotron). At the 90% confidence limit, B(eta-->4pi(0))
Published: 2000
Full Text: View/download PDF

16. Investigation of nuclear charge symmetry by pion elastic scattering from 3H and 3He.

Author: Dhuga KS, Berman BL, Briscoe WJ, Caress RW, Matthews SK, Barlow DB, Nefkens BM, Pillai C, Price JW, Greene SJ, Slaus I I, and Supek I I
Published: 1996
Full Text: View/download PDF

17. The d

Author: Nikulin VN, Boudard A, Clajus M, Fabbro B, Garçon M, Kessler RS, Lytkin LK, Mayer B, Nefkens BM, Plouin F, Poitou J, Tomasi-Gustafsson E, van Oers WT, White D, and Wilkin C
Published: 1996
Full Text: View/download PDF

18. Search for the decays eta --> microe and eta -->e+e-

Author: White DB, Tippens WB, Abegg R, Baldisseri A, Boudard A, Briscoe W, Fabbro B, Garçon M, Hermes EA, Jacobs WW, Kessler RS, Lytkin L, Mayer B, Nefkens BM, Niebuhr C, Petrov AM, Poitou J, Saudinos J, Tomasi-Gustafsson E, van der Schaaf A, van Oers WT, Vigdor SE, and Wang M
Published: 1996
Full Text: View/download PDF

19. Reactions pd-->3He eta and pd-->3He pi + pi - near the eta threshold.

Author: Mayer B, Boudard A, Fabbro B, Garçon M, Kerboul C, Poitou J, Wellers F, Jacobs WW, Saudinos J, Tomasi-Gustafsson E, Mouly JP, Kessler RS, Nefkens BM, Tippens B, van der Schaaf A, Abegg R, van Oers WT, Briscoe W, Petrov A, and Moalem A
Published: 1996
Full Text: View/download PDF

20. Direct measurement of the branching ratio for the decay of the eta meson into two photons.

Author: Abegg R, Abela R, Boudard A, Briscoe W, Clajus M, Durand J, Efendiev A, Fabbro B, Fuchs P, Garçon M, Lytkin L, Mayer B, Morrison T, Nefkens BM, Nikulin V V, Pillot J, Tomasi-Gustafsson E, White D, and van Oers WT
Published: 1996
Full Text: View/download PDF

21. S-wave resonance coupled-channel approach to the reactions pi -+p--> eta +n and K-+p--> eta + Lambda, and a determination of the eta n and eta Lambda scattering lengths.

Author: Abaev VV and Nefkens BM
Published: 1996
Full Text: View/download PDF

22. eta meson photoproduction on hydrogen near threshold.

Author: Price JW, Anton G, Arends J, Beulertz W, Bock A, Breuer M, Büchler K, Clajus M, Detemple P, Hey J, Krämer D, Meyer W, Nefkens BM, Nöldeke G, Schneider W, and Zucht B
Published: 1995
Full Text: View/download PDF

23. pi N--> eta N and eta N--> eta N partial-wave T matrices in a coupled, three-channel model.

Author: Batinic M, Slaus I I, Svarc A, and Nefkens BM
Published: 1995
Full Text: View/download PDF

24. Elastic scattering of pions from 3H and 3He into the backward hemisphere.

Author: Matthews SK, Briscoe WJ, Bennhold C, Berman BL, Caress RW, Dhuga KS, Dragic SN, Kamalov SS, Nicholas NJ, Taragin MF, Tiator L, Greene SJ, Barlow DB, Nefkens BM, Pillai C, Price JW, Isenhower LD, Sadler ME, Slaus I I, and Supek I I
Published: 1995
Full Text: View/download PDF

25. Inelastic pion scattering from 3H and 3He.

Author: Berman BL, Anderson GC, Briscoe WJ, Mokhtari A, Petrov AM, Sadler ME, Barlow DB, Nefkens BM, and Pillai C
Published: 1995
Full Text: View/download PDF

26. Measurement of the branching ratio for the decay eta --> micro+ micro-

Author: Abegg R, Baldisseri A, Boudard A, Briscoe W, Fabbro B, Garçon M, Hermes EA, Jacobs WW, Kessler RS, Lytkin L, Mayer B, Nefkens BM, Niebuhr C, Petrov AM, Poitou J, Saudinos J, Tippens B, Tomasi-Gustafsson E, van der Schaaf A, van Oers WT, Vigdor SE, Wang M, and White D
Published: 1994
Full Text: View/download PDF

27. Total cross section of the pp-->pp eta reaction near threshold.

Author: Bergdolt AM, Bergdolt G, Bing O, Bouchakour A, Brochard F, Hibou F, Moalem A, Taleb A, Combes-Comets MP, Courtat P, Gacougnolle R, Le Bornec Y, Loireleux E, Reide F, Tatischeff B, Willis N, Boivin M, Nefkens BM, and Plouin F
Published: 1993
Full Text: View/download PDF

28. Spin-rotation parameters A and R for pi +p and pi -p elastic scattering from 427 to 657 MeV/c.

Author: Supek I I, Barlow DB, Briscoe WJ, Davis JF, Kim GJ, Lane DW, Mokhtari A, Nefkens BM, Pillai C, Sadler ME, Seftor CJ, Taragin MF, and Wightman JA
Published: 1993
Full Text: View/download PDF

29. Measurement of the branching ratio for the decay eta --> micro+ micro-

Author: Kessler RS, Abegg R, Baldisseri A, Boudard A, Briscoe W, Fabbro B, Garçon M, Hermes EA, Jacobs WW, Lytkin L, Mayer B, Nefkens BM, Niebuhr C, Petrov AM, Poitou J, Saudinos J, Tippens B, Tomasi-Gustafsson E, van der Schaaf A, van Oers WT, Vigdor SE, Wang M, and White D
Published: 1993
Full Text: View/download PDF

30. 3He and 4He production by 800 MeV protons from 12C, Ti, and Pb at forward angles.

Author: Barlow DB, Nefkens BM, Pillai C, Price JW, Slaus I I, Wang MJ, Wightman JA, Jones KW, Leitch MJ, Mishra CS, Morris CL, Peng JC, Teng PK, and Tinsley JM
Published: 1992
Full Text: View/download PDF

31. Angle and energy dependence of the superratio for pi + and pi - elastic scattering from H3 and He3: Evidence for charge-symmetry violation.

Author: Pillai C, Barlow DB, Berman BL, Briscoe WJ, Mokhtari A, Nefkens BM, and Sadler ME
Published: 1991
Full Text: View/download PDF

32. Measurement of the left-right asymmetry in pi -p--> gamma n from 301 to 625 MeV/c at backward angles.

Author: Kim GJ, Engelage J, Nefkens BM, Ziock HJ, Arends J, Briscoe WJ, and Sadler ME
Published: 1991
Full Text: View/download PDF

33. Superratio and the simple ratios of pi + and pi - elastic scattering on 3H and 3He at 180 MeV to investigate charge symmetry.

Author: Nefkens BM, Briscoe WJ, Eichon AD, Fitzgerald DH, Mokhtari A, Wightman JA, and Sadler ME
Published: 1990
Full Text: View/download PDF

34. Analyzing power for pi -p charge exchange in the backward hemisphere from 301 to 625 MeV/c and a test of pi N partial-wave analyses.

Author: Kim GJ, Arends J, Briscoe WJ, Engelage J, Nefkens BM, Sadler ME, Taragin M, and Ziock HJ
Published: 1990
Full Text: View/download PDF

35. Left-right asymmetry in inverse pi - photoproduction from a transversely polarized proton target.

Author: Kim GJ, Adrian SD, Arends J, Briscoe WJ, Eichon AD, Engelage J, Graessle S, Nefkens BM, Ohashi Y, Sadler ME, Seftor CJ, Sober DI, Taragin M, and Ziock HJ
Published: 1986
Full Text: View/download PDF

36. Recoil-proton polarization in pi p elastic scattering at 547 and 625 MeV/c.

Author: Seftor CJ, Adrian SD, Briscoe WJ, Mokhtari A, Taragin MF, Sadler ME, Barlow DB, Nefkens BM, and Pillai C
Published: 1989
Full Text: View/download PDF

37. Analyzing power for pi -p charge exchange and a test of isospin invariance up to eta threshold.

Author: Wightman JA, Eichon AD, Kim GJ, Mokhtari A, Nefkens BM, Fitzgerald DH, and Sadler ME
Published: 1987
Full Text: View/download PDF

38. Differential cross sections for p+d--> gamma +3He at intermediate energies.

Author: Briscoe WJ, Silverman BH, Fitzgerald DH, Nefkens BM, Boudard A, Bruge G, Farvacque L, and Glashausser C
Published: 1985
Full Text: View/download PDF

39. pi -p charge-exchange analyzing power from 547 to 687 MeV/c.

Author: Wightman JA, Eichon AD, Kim GJ, Mokhtari A, Nefkens BM, Briscoe WJ, Fitzgerald DH, and Sadler ME
Published: 1988
Full Text: View/download PDF

40. Measurement of the spin-rotation parameters A and R for pi +p--> pi +p and pi -p--> pi -p scattering from 471 to 625 MeV/c.

Author: Barlow DB, Kessler RS, Kim GJ, Nefkens BM, Pillai C, Price JW, Wightman JA, Hall S, Lane DW, Loe SR, Morton LK, Sadler ME, Adrian SD, Briscoe WJ, Kramer LH, Mokhtari A, Petrov AM, Seftor CJ, Taragin MF, Davis JF, and Supek I I
Published: 1989
Full Text: View/download PDF

41. Analyzing power and transversity cross sections for pi +p and pi -p elastic scattering from 471 to 687 MeV/c.

Author: Mokhtari A, Eichon AD, Kim GJ, Nefkens BM, Wightman JA, Fitzgerald DH, Briscoe WJ, and Sadler ME
Published: 1987
Full Text: View/download PDF

42. Analyzing power for pi -p elastic scattering in the energy region of the Roper resonance.

Author: Mokhtari A, Briscoe WJ, Eichon AD, Fitzgerald DH, Kim GJ, Nefkens BM, Wightman JA, and Sadler ME
Published: 1986
Full Text: View/download PDF

43. Differential cross section for pi -p--> gamma n from 427 to 625 MeV/c.

Author: Kim GJ, Arends J, Briscoe WJ, Engelage J, Nefkens BM, Sadler ME, and Ziock HJ
Published: 1989
Full Text: View/download PDF

44. Analyzing powers in pi +p elastic scattering at intermediate energies.

Author: Mokhtari A, Briscoe WJ, Eichon AD, Fitzgerald DH, Kim GJ, Nefkens BM, Wightman JA, Adrian SD, Sadler ME, and Walker T
Published: 1985
Full Text: View/download PDF

45. Differential cross sections for pi +p and pi -p elastic scattering from 378 to 687 MeV/c.

Author: Sadler ME, Briscoe WJ, Fitzgerald DH, Nefkens BM, and Seftor CJ
Published: 1987
Full Text: View/download PDF

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

45 results on '"Nefkens BM"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources