Fragmentation of 7 Li relativistic nuclei on a proton into the 3 H + 4 He channel

In a track nuclear photoemulsion exposed to a beam of 7 Li nuclei accelerated to a momentum of 3 GeV/ c per nucleon at the synchrophasotron of the Joint Institute for Nuclear Research (JINR, Dubna), 13 events in which 7 Li nuclei interacting with protons break up into 3 H and 4 He fragments were detected among 3730 inelastic-interaction events. For this fragmentation channel, the cross section was found to be 8 ± 2 mb. The average value of the fragment total transverse momentum was 214 ± 5 MeV/ c . This value exceeds markedly the average value of the transverse-momentum transfer in the coherent dissociation of 7 Li nuclei on track-emulsion nuclei (166±5MeV/ c ). The recoil-proton transverse momentum was on average 98% of the total proton momentum. The longitudinal-momentum distribution of protons was characterized by a variance of 16 MeV/ c and a mean value of 37 ± 2MeV/ c .