Hard photon and neutral pion production in cold nuclear matter

0185902 - UJF-V 20033209 RIV NL eng J - Journal Article
Aphecetche, L. - Bacelar, J. - Delagrange, H. - d'Enterria, D. - Hoefman, M. - Huisman, H. - Kalantar-Nayestanaki, N. - Löhner, H. - Martínez, G. - Matulewicz, T. - Messchendorp, J. - Mora, MJ. - Ostendorf, R. W. - Schadmand, S. - Schutz, Y. - Seip, M. - Taranenko, Arkadij - Turrisi, R. - Van Goethem, MJ. - Volkerts, M. - Wagner, Vladimír - Wilschut, H. W.
Hard photon and neutral pion production in cold nuclear matter.
Physics Letters. B. Roč. 519, - (2001), s. 8-14. ISSN 0370-2693. E-ISSN 1873-2445
Institutional research plan: CEZ:AV0Z1048901
Keywords : proton-nucleus reactions * hard photons * subthreshold pions
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders
Impact factor: 4.377, year: 2001

The production of hard photons and neutral pions in 190 MeV proton induced reactions on C, Ca. Ni, and W targets has been for the first time concurrently studied. Angular distributions and energy spectra up to the kinematical limit are discussed and the production cross-sections are presented. From the target mass dependence of the cross-sections the propagation of pions through nuclear matter is analyzed and the production mechanisms of hard photons and primordial pions are derived. It is found that the production of subthreshold particles proceeds mainly through first chance nucleon-nucleon collisions. For the most energetic particles the mass scaling evidences the effect of multiple collisions.
Permanent Link: http://hdl.handle.net/11104/0082253