Description: Lineshape of the Lambda (1405) hyperon measured through its Sigma+ pi0 decay

This title appears in the Scientific Report : 2008

Lineshape of the Lambda (1405) hyperon measured through its Sigma+ pi0 decay

The pp --> pK(+)Y(0) reaction has been studied for hyperon masses m (Y-0) <= 1540 MeV/c(2) at COSY-Julich by using a 3.65 GeV/c circulating proton beam incident on an internal hydrogen target. Final states comprising two protons, one positively charged kaon and one negatively charged pion have...

Personal Name(s):	Zychor, I.
	Büscher, M. / Hartmann, M. / Kacharava, A. / Keshelashvili, I. / Khoukaz, A. / Kleber, V. / Koptev, V. / Maeda, Y. / Mersmann, T. / Mikirtychiants, S. / Schleichert, R. / Ströher, H. / Valdau, Yu. / Wilkin, C.
Contributing Institute:	Experimentelle Hadrondynamik; IKP-2 Jülich-Aachen Research Alliance - Simulation Sciences; JARA-SIM
Published in:	Physics letters / B, 660 (2008) S. 167 - 171
Imprint:	Amsterdam North-Holland Publ. 2008
Physical Description:	167 - 171
DOI:	10.1016/j.physletb.2008.01.002
Document Type:	Journal Article
Research Program:	Physik der Hadronen und Kerne
Series Title:	Physics Letters B 660
Subject (ZB):	Lambda(1405): hadronic decay p p: interaction Juelich COSY PS hyperon resonances line shapes
Link:	Get full text OpenAccess OpenAccess
	Publikationsportal JuSER

Please use the identifier: http://hdl.handle.net/2128/10518 in citations.
Please use the identifier: http://dx.doi.org/10.1016/j.physletb.2008.01.002 in citations.

The pp --> pK(+)Y(0) reaction has been studied for hyperon masses m (Y-0) <= 1540 MeV/c(2) at COSY-Julich by using a 3.65 GeV/c circulating proton beam incident on an internal hydrogen target. Final states comprising two protons, one positively charged kaon and one negatively charged pion have been identified with the ANKE spectrometer. Such configurations are sensitive to the production of the ground state Lambda and Sigma(0) hyperons as well as the Sigma(0)(1385) and Lambda(1405) resonances. Applying invariant- and missing-mass techniques, the two overlapping excited states could be well separated, though with limited statistics. The shape and position of the Lambda(1405) distribution, reconstructed cleanly in the Sigma(0)pi(0) channel, are similar to those found from other decay modes and there is no obvious mass shift. This finding constitutes a challenging test for models that predict Lambda( 1405) to be a two-state resonance. (C) 2008 Elsevier B.V. All rights reserved.