Study of the reaction pp \to pp$Ï^{0}$ within 10 MeV above the threshold

TOF collaboration

doi:10.1140/epja/i2002-10164-y

paper

Study of the reaction pp \to pp $I ¨ ^{0}$ within 10 MeV above the threshold

arXiv:nucl-ex/0212024 · doi:10.1140/epja/i2002-10164-y

Abstract

Kinematically complete measurements of the $pp \to pp I ¨ ^{0}$ reaction were performed for beam energies in the range $292 - 298$ MeV. By detecting both protons in coincidence with the large acceptance COSY-TOF spectrometer set up at an external beam line of the proton synchrotron COSY-JÃ¼lich, total and differential cross sections and energy distributions were obtained. A strong enhancement is observed in the Dalitz plots resulting from the final state interaction between the outgoing proton pair; the data are well reproduced by Monte Carlo simulations with standard parameters for scattering length $a_{0}$ =-7.83 fm and effective range $r_{0}$ =2.8 fm. The total cross sections exceed the ones measured recently in internal target experiments at IUCF and CELSIUS by roughly 50%. Arguments are presented which link this discrepancy with the effect of the final state interaction pushing yield into the very small-angle region and the near-impossibility of an internal target experiment to cover just this range.

25 pages including 12 figures

Study of the reaction pp \to ppI¨0 within 10 MeV above the threshold

Abstract

Study of the reaction pp \to pp $I ¨ ^{0}$ within 10 MeV above the threshold