%0 Journal Article
%T Antiproton Production in $p+A$ Collisions at AGS Energies
%A I. Chemakin
%A V. Cianciolo
%A B. A. Cole
%A R. Fernow
%A A. Frawley
%A M. Gilkes
%A S. Gushue
%A E. Hartouni
%A H. Hiejima
%A M. Justice
%A J. H. Kang
%A D. Keane
%A H. Kirk
%A M. Kreisler
%A N. Maeda
%A R. L. McGrath
%A S. Mioduszewski
%A D. Morrison
%A M. Moulson
%A N. Namboodiri
%A G. Rai
%A K. Read
%A L. Remsberg
%A M. Rosati
%A Y. Shin
%A R. Soltz
%A S. Sorensen
%A J. Thomas
%A Y. Torun
%A D. Winter
%A X. Yang
%A W. A. Zajc
%A Y. Zhang
%J Physics
%D 2001
%I arXiv
%R 10.1103/PhysRevC.64.064908
%X Inclusive and semi-inclusive measurements are presented for antiproton ($\bar{p}$) production in proton-nucleus collisions at the AGS. The inclusive yields per event increase strongly with increasing beam energy and decrease slightly with increasing target mass. The $\bar{p}$ yield in 17.5 GeV/c p+Au collisions decreases with grey track multiplicity, $N_g$, for $N_g>0$, consistent with annihilation within the target nucleus. The relationship between $N_g$ and the number of scatterings of the proton in the nucleus is used to estimate the $\bar{p}$ annihilation cross section in the nuclear medium. The resulting cross section is at least a factor of five smaller than the free $\bar{p}-p$ annihilation cross section when assuming a small or negligible formation time. Only with a long formation time can the data be described with the free $\bar{p}-p$ annihilation cross section.
%U http://arxiv.org/abs/nucl-ex/0107013v1