1.
Phys Rev Lett
; 86(22): 5019-22, 2001 May 28.
Artigo
em Inglês
| MEDLINE
| ID: mdl-11384410
RESUMO
We measured the invariant mass spectra of electron-positron pairs in the target rapidity region of 12-GeV p+A reactions. We have observed a significant difference in the mass spectra below the omega meson between p+C and p+Cu interactions. This difference indicates that the spectral shape of mesons is modified at normal nuclear-matter density.