Studies of $$\Lambda n$$ interaction through polarization observables for final-state interactions in exclusive $$\Lambda$$ photoproduction off the deuteron

Conference · Wed Jun 01 00:00:00 EDT 2016 · Proceedings of Science

OSTI ID:1263532

Ilieva, Yordanka ^[1]; Cao, Tongtong ^[1]; Zachariou, Nicholas ^[2]

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1. Univ. of South Carolina, Columbia, SC (United States)
2. Univ. of Edinburgh, Scotland (United Kingdom)

Theoretical studies suggest that experimental observables for hyperon production reactions can place stringent constraints on the free parameters of hyperon-nucleon potentials, which are critical for the understanding of hypernuclear matter and neutron stars. Here we present preliminary experimental results for the polarization observables S, Py, Ox, Oz, Cx, and Cz for final-state interactions (FSI) in exclusive L photoproduction off the deuteron. The observables were obtained from data collected during the E06-103 (g13) experiment with the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B at Jefferson Lab. The g13 experiment ran with unpolarized deuteron target and circularly- and linearly-polarized photon beams with energies between 0.5 GeV and 2.5 GeV and collected about 51010 events with multiple charged particles in the final state. To select the reaction of interest, the K+ and the L decay products, a proton and a negative pion, were detected in the CLAS. The missing-mass technique was used to identify exclusive hyperon photoproduction events. Final-state interaction events were selected by requesting that the reconstructed neutron has a momentum larger than 200 MeV/c. The large statistics of E06-103 provided statistically meaningful FSI event samples, which allow for the extraction of one- and two-fold differential single- and double-polarization observables. Here we present preliminary results for a set of six observables for photon energies between 0.9 GeV and 2.3 GeV and for several kinematic variables in the Ln center-of-mass frame. Our results are the very first estimates of polarization observables for FSI in hyperon photoproduction and will be used to constrain the free parameters of hyperon-nucleon potentials.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Contributing Organization: CLAS Collaboration
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1263532
• Report Number(s): JLAB-PHY-16-2228; DOE/OR/23177-3855
• Journal Information: Proceedings of Science, Vol. CD15; Conference: 8th International Workshop on Chiral Dynamics (CD15) , 29 Jun - 03 Jul 2015. Pisa, Italy
• Country of Publication: United States
• Language: English