Cairo University

MTPR Journal

 

SEARCH ON e+ - e- PAIR AND OBSERVATION OF A NEW LIGHT NEUTRAL BOSON

& doi: https://doi.org/10.1142/9789814317511_0031
M. S. EL-NAGDY, A. ABDELSALAM and B. M. BADAWY
Physics Department, Faculty of Science, Helwan University, Helwan, Egypt
Physics Department, Faculty of Science, Helwan University, Helwan, Egypt
Reactor Physics Department, Nuclear Research Center, Atomic Energy Authority, Egypt


Vol./Issue: 11 , id: 334

We present a unified description of e+ e- dilepton production in heavy ion collisions at relativistic (3.7A GeV) and ultrarelativistic (200A GeV) energies. From the interactions of [12C and 22Ne] at 3.7A GeV and 32S at 200A GeV with nuclear emulsion, 134 e+ e- pairs are observed. The differential distribution of the energy asymmetry of pairs is compared to a background observation at Bristol. The events are consistent in a way that, they scale well in a single curve of exponential decay. This ensures correct asymptotics and provides a unified description of mesonic decay. The existence of light neutral boson of mass (1.55±0.14 MeV/c2) is questionable, because the candidate peak is seen in the invariant mass spectrum of its decay into e+ e- pairs. The data seem to suggest the production and subsequent decay of short lived neutral boson with lifetime of the order of 10-16 S.