Description: Systematic study of the pp to pp omega reaction

This title appears in the Scientific Report : 2010

Systematic study of the pp to pp omega reaction

A systematic study of the production of omega-mesons in proton-proton collisions was carried out in a kinematically complete experiment at three excess energies (epsilon = 92, 128, 173MeV). Both protons were detected using the large-acceptance COSY-TOF spectrometer at an external beam line at the Co...

Personal Name(s):	Abdel-Bary, M.
	AbdEl-Samad, S. / Brinkmann, K. / Clement, H. / Dietrich, J. / Dorochkevitch, E. / Dshemuchadse, S. / Ehrhardt, K. / Erhardt, A. / Eyrich, W. / Fanara, C. / Filges, D. / Filippi, A. / Freiesleben, H. / Fritsch, M. / Gast, W. / Georgi, J. / Gillitzer, A. / Gottwald, J. / Hesselbarth, D. / Jaeger, H. / Jakob, B. / Jaekel, R. / Karsch, L. / Kilian, K. / Koch, H. / Krapp, M. / Kress, J. / Kuhlmann, E. / Lehmann, A. / Marcello, S. / Marwinski, S. / Mauro, S. / Meyer, W. / Michel, P. / Moeller, K. / Moertel, H. / Morsch, H.P. / Naumann, L. / Paul, N. / Pinna, L. / Pizzolotto, C. / Plettner, C. / Reimann, S. / Richter, M. / Ritman, J. / Roderburg, E. / Schamlott, A. / Schoenmeier, P / Schulte-Wissermann, M. / Schroeder, W. / Sefzick, T. / Steinke, M. / Stinzing, F. / Sun, G. / Teufel, A. / Ullrich, W. / Waechter, J. / Wagner, G. J. / Wagner, M. / Wenzel, R. / Wilms, A. / Wintz, P. / Wirth, S. / Wuestner, P. / Zupranski, P.
Contributing Institute:	Experimentelle Hadronstruktur; IKP-1
Published in:	The @European physical journal / A, 44 (2010) S. 7 - 22
Imprint:	Berlin Springer 2010
Physical Description:	7 - 22
DOI:	10.1140/epja/i2010-10924-0
Document Type:	Journal Article
Research Program:	Physik der Hadronen und Kerne
Series Title:	European Physical Journal A 44
Subject (ZB):	p p: interaction omega(783): hadroproduction total cross section: energy dependence p: angular distribution meson: production meson: spin meson: model COSY-TOF Juelich COSY PS p p > > p p omega(783)
Link:	Get full text OpenAccess OpenAccess
	Publikationsportal JuSER

Please use the identifier: http://dx.doi.org/10.1140/epja/i2010-10924-0 in citations.
Please use the identifier: http://hdl.handle.net/2128/10325 in citations.

A systematic study of the production of omega-mesons in proton-proton collisions was carried out in a kinematically complete experiment at three excess energies (epsilon = 92, 128, 173MeV). Both protons were detected using the large-acceptance COSY-TOF spectrometer at an external beam line at the Cooler Synchrotron COSY at Forschungszentrum Julich. The total cross-section, angular distributions of both omega-mesons and protons were measured and presented in various reference frames such as the overall CMS, helicity and Jackson frame. In addition, the orientation of the omega-spin and invariant-mass spectra were determined. We observe omega-production to take place dominantly in Ss and Sp final states at epsilon = 92, 128MeV and, additionally, in Sd at epsilon = 173MeV. No obvious indication of resonant omega-production via N*-resonances was found, as proton angular distributions are almost isotropic and invariant-mass spectra are compatible with phase space distributions. A dominant role of P-3(1) and S-1(0) initial partial waves for omega-production was concluded from the orientation of the decay plane of the omega-meson. Although the Jackson angle distributions in the omega p-Jackson frame are anisotropic we argue that this is not an indication of a resonance but rather a kinematical effect reflecting the anisotropy of the omega angular distribution. The helicity angle distribution in the omega p-helicity frame shows an anisotropy which probably reflects effects of the omega angular momenta in the final state; this observable may be, in addition to the orientation of the omega decay plane, the most sensitive one to judge the validity of theoretical descriptions of the production process.