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J. G. Messchendorp 《Few-Body Systems》2011,50(1-4):97-103
Understanding the few-nucleon system remains one of the challenges in modern nuclear and hadron physics. Observables in few-nucleon scattering processes are sensitive probes to study the two and many-body interactions between nucleons in nuclei. In the past decades, several facilities provided a large data base to study in detail the three-nucleon interactions below the pion-production threshold by exploiting polarized proton and deuteron beams and large-acceptance detectors. Only since recently, the four-nucleon scattering process at intermediate energies has been explored. In addition, there is a focus to collect data in the hyperon-nucleon sector, thereby providing access to understand the more general baryon-baryon interaction. In this contribution, some recent results in the few-nucleon sector are discussed together with some of the preliminary results from a pioneering and exclusive study of the four-nucleon scattering process. Furthermore, this paper discusses the experimental activities in the hyperon sector, in particular, the perspectives of the hyperon program of PANDA. 相似文献
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Bartholomy O Credé V van Pee H Anisovich AV Anton G Bantes R Beloglazov Y Bogendörfer R Castelijns R Ehmanns A Ernst J Fabry I Flemming H Fösel A Freiesleben H Fuchs M Funke Ch Gothe R Gridnev A Gutz E Höffgen SK Horn I Hössl J Joosten R Junkersfeld J Kalinowsky H Klein F Klempt E Koch H Konrad M Kopf B Krusche B Langheinrich J Löhner H Lopatin I Lotz J Matthäy H Menze D Messchendorp J Morales C Novinski D Ostrick M Radkov A Reinnarth J Sarantsev AV Schadmand S Schmidt Ch Schmieden H Schoch B 《Physical review letters》2005,94(1):012003
Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15. 相似文献
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B. Krusche J. Lehr J. Ahrens J. R. M. Annand R. Beck F. Bloch L. S. Fog D. Hornidge S. Janssen M. Kotulla J. C. McGeorge I. J. D. MacGregor J. Messchendorp V. Metag U. Mosel R. Novotny R. O. Owens M. Pfeiffer R. Sanderson S. Schadmand D. P. Watts 《The European Physical Journal A - Hadrons and Nuclei》2004,22(2):277-291
Photoproduction of neutral pions from nuclei (carbon, calcium, niobium, lead) has been studied for incident-photon energies from 200 MeV to 800 MeV with the TAPS detector using the Glasgow photon tagging spectrometer at the Mainz MAMI accelerator. Data were obtained for the inclusive photoproduction of neutral pions and the partial channels of quasifree single-
, double-
, and
photoproduction. They have been analyzed in terms of the in-medium behavior of nucleon resonances and the pion-nucleus interaction. They are compared to earlier measurements from the deuteron and to the predictions of a Boltzmann-Uehling-Uhlenbeck (BUU) transport model for photon-induced pion production from nuclei.PACS:
13.60.Le Meson production - 25.20.Lj Photoproduction reactions 相似文献
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J. G. Messchendorp 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):417-419
Preliminary differential cross-sections of the reactions
and
with A = 1
H, 12
C, and
nat
Pb are presented. A significant nuclear-mass dependence of the
invariant-mass distribution is found in the
channel. The dependence is not observed in the
channel. The in-medium observation in the
channel is consistent with an in-medium modification of the
interaction in the I = J = 0 channel, changing width and pole position of a
resonant state.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.60.Le Meson production - 21.65. + f Nuclear matterJ.G. Messchendorp: For the TAPS and A2 Collaborations 相似文献
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Hoefman M Aphecetche L Bacelar JC Delagrange H Descouvemont P Diaz J d'Enterria D van Goethem M Holzmann R Huisman H Kalantar-Nayestanaki N Kugler A Lohner H Marques FM Martinez G Messchendorp JG Ostendorf RW Schadmand S Siemssen RH Simon RS Schutz Y Timmermans R Turrisi R Volkerts M Wagner V Weller H 《Physical review letters》2000,85(7):1404-1407
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H. Mardanpour H. R. Amir-Ahmadi A. Deltuva K. Itoh N. Kalantar-Nayestanaki T. Kawabata H. Kuboki Y. Maeda J. G. Messchendorp S. Sakaguchi H. Sakai N. Sakamoto Y. Sasamoto M. Sasano K. Sekiguchi K. Suda Y. Takahashi T. Uesaka H. Witała K. Yako 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):383-391
High-precision vector and tensor analyzing powers of elastic deuteron-proton ( d + p) scattering have been measured at intermediate energies to investigate effects of three-nucleon forces. Angular distributions
in the range of 70°-120° in the center-of mass frame for incident-deuteron energies E
d
lab = 130 and 180 MeV were obtained using the RIKEN facility. The beam polarization was unambiguously determined by measuring
the ^12C (d, α)^10B(2+) reaction at 0°. Results of the measurements are compared with state-of-the-art three-nucleon calculations. The present modeling of nucleon-nucleon
forces and its extension to the three-nucleon system is not sufficient to describe the high-precision data consistently and
requires, therefore, further investigation. 相似文献
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H. Mardanpour H. R. Amir-Ahmadi R. Benard A. Biegun M. Eslami-Kalantari N. Kalantar-Nayestanaki M. Kiš St. Kistryn A. Kozela H. Kuboki Y. Maeda M. Mahjour-Shafiei J. G. Messchendorp K. Miki S. Noji A. Ramazani-Moghaddam-Arani H. Sakai M. Sasano K. Sekiguchi E. Stephan R. Sworst Y. Takahashi K. Yako 《Few-Body Systems》2008,44(1-4):49-52
A systematic study of three-nucleon force (3NF) effects in break-up reactions has been carried out at KVI at several energies. In this article, the p + d → p + p + n reaction with a polarized-proton beam of 190?MeV will be discussed. The experiment was performed by exploiting a new detector called BINA. Some results for high-precision vector analyzing powers and differential cross sections are presented and compared with state-of-the-art Faddeev calculations with or without 3NF. 相似文献
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