Eur. Phys. J. A (2010) 43: 131-136
https://doi.org/10.1140/epja/i2009-10900-9

Regular Article - Experimental Physics

Invariant-mass distributions for the pp pp reaction at Q = 10 MeV

¹ Institute of Physics, Jagellonian University, PL-30-059, Cracow, Poland
² Nuclear Physics Institute, Research Center Jülich, D-52425, Jülich, Germany
³ Institute of Physics, University of Silesia, PL-40-007, Katowice, Poland
⁴ IKP, Westfälische Wilhelms-Universität, D-48149, Münster, Germany
⁵ Department of Physics and Astronomy, SE-751 05 Uppsala University, Uppsala, Sweden

^* e-mail: p.moskal@fz-juelich.de

Received: 7 July 2008
Revised: 12 October 2009
Accepted: 18 November 2009
Published online: 17 December 2009

Abstract

Proton-proton and proton- invariant-mass distributions and the total cross-section for the pp pp reaction have been determined near the threshold at an excess energy of Q = 10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q = 15.5 MeV and Q = 40 MeV.