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

Abstract

Kinematically complete measurements of the $pp\to pp{\pi }^0$ 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-Jülich, 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.

arXiv comment25 pages including 12 figures

References in corpus (8)

• Nucleon-nucleon elastic scattering to 3 GeV
• The $pp\to pp{\pi }^0$ Reaction near Threshold: A Chiral Power Counting Approach
• Chiral Perturbation Approach to the pp -> pp pi0 Reaction Near Threshold
• Role of the $\Delta$ isobar in the reaction $NN\to NN\pi$ near threshold
• Meson Exchange and Pion Rescattering Contributions to the Cross Section for $pp\to pp{\pi }^0$
• Polarization phenomena in the reaction NN to NNpi near threshold
• Nucleon Resonance Effects in $pp\to pp{\pi }^0$ near Threshold
• Spin correlations in $\vec{p}\vec{p}\to pn{\pi }^{+}$ pion production near threshold

Cited by in corpus (8)

• Parametrization of gamma-ray production cross-sections for pp interactions in a broad proton energy range from the kinematic threshold to PeV energies
• Experimental study of pp eta dynamics in the pp --> ppeta reaction
• p-Wave pion production from nucleon-nucleon collisions
• Single-Pion Production in pp Collisions at =.95 GeV/c (I)
• Exclusive $pp\to pp{\pi }^0$ reaction at high energies
• Anisotropy in the pion angular distribution of the reaction pp -> pp pi0 at 400 MeV
• Single π^- production in np collisions for excess energies up to 90 MeV
• Differential cross section and analyzing power of the $\vec{p}p\to pp{\pi }^0$ reaction at a beam energy of 390 MeV