New measurements of the pp total annihilation cross-section at very low momenta (around 50 MeV/c) confirm the previous results obtained by the OBELIX collaboration. The measured values are in general agreement with a scattering length approximation of the annihilation cross-section where the <(p)over bar p> scattering lengths are obtained from measurement of the protonium shifts and widths and which accounts for the Coulomb interaction. Partial annihilation cross-sections and annihilation frequencies for some channels have been measured too. The values of the total and partial cross sections at the lowest (p) over bar momentum show an unexpected behaviour. RI Galli, Domenico/A-1606-2012; Iazzi, Felice/F-4490-2012; Botta, Elena/G-9742-2012; Villa, Mauro/C-9883-2009; Fontana, Andrea/I-4375-2012; Filippi, Alessandra/I-9530-2012
P(P)over-bar partial cross sections at low energy
Cicalo C;PUDDU, GIOVANNA;USAI, GIANLUCA;
1997-01-01
Abstract
New measurements of the pp total annihilation cross-section at very low momenta (around 50 MeV/c) confirm the previous results obtained by the OBELIX collaboration. The measured values are in general agreement with a scattering length approximation of the annihilation cross-section where the <(p)over bar p> scattering lengths are obtained from measurement of the protonium shifts and widths and which accounts for the Coulomb interaction. Partial annihilation cross-sections and annihilation frequencies for some channels have been measured too. The values of the total and partial cross sections at the lowest (p) over bar momentum show an unexpected behaviour. RI Galli, Domenico/A-1606-2012; Iazzi, Felice/F-4490-2012; Botta, Elena/G-9742-2012; Villa, Mauro/C-9883-2009; Fontana, Andrea/I-4375-2012; Filippi, Alessandra/I-9530-2012I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.