We report on measurements of low-mass electron pairs in 450 GeV p-Be, p-Au, and 200 GeV/nucleon S-Au collisions at central rapidities. For the proton induced interactions, the low-mass spectra are, within the systematic errors, satisfactorily explained by electron pairs from hadron decays, whereas in the S-Au system an enhancement over the hadronic contributions by a factor of 5.0+/-0.7\(stat\)+/-2.0\(syst\) in the invariant mass range 0.2<m<1.5 GeV/c2 is observed. The properties of the excess suggest that it arises from two-pion annihilation ππ-->e+e-.
Enhanced Production of Low-Mass Electron Pairs in 200 GeV/Nucleon S-Au Collisions at the CERN-Super Proton Synchrotron
GATTI, EMILIO;SAMPIETRO, MARCO;
1995-01-01
Abstract
We report on measurements of low-mass electron pairs in 450 GeV p-Be, p-Au, and 200 GeV/nucleon S-Au collisions at central rapidities. For the proton induced interactions, the low-mass spectra are, within the systematic errors, satisfactorily explained by electron pairs from hadron decays, whereas in the S-Au system an enhancement over the hadronic contributions by a factor of 5.0+/-0.7\(stat\)+/-2.0\(syst\) in the invariant mass range 0.2File in questo prodotto:
Non ci sono file associati a questo prodotto.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
