Advisors: Dan Carman, Jefferson Lab Paul Padley , Rice University

Advisors: Dan Carman, Jefferson Lab Paul Padley, Rice University

February 15, 2010APS 2010 April Meeting

Paul Mattione, Rice University

for the CLAS Collaboration

K(892)*0Λ and K+Σ(1385) - Photoproduction on the

Deuteron

Overview Missing N* resonances

Predicted by quark models High mass N* states: wide, overlapping Most current information comes from πN analyses Coupling to Y and Y* decay channels (e.g. N(2190)G17****) ł

γD -> K(892)*0Λ(p) and γD -> K+Σ(1385)-(p) Same final state (p, K+, π-, π-) Intend to measure cross sections for both

Jefferson Lab CLAS g13a data (October 2006 – June 2007) Ee 2.0, 2.65 GeV, circularly polarized photons Event selection K(892)*0Λ, K+Σ(1385)- interference and yields Acceptance correction in progress



ł Capstick, Roberts; Phys Rev D, 58 074011 (1998)

K(892)*0Λ Predictions Model based on effective Lagrangians Cross-sections predominantly t-channel process (red lines) However, in the s-channel calculations only the Born term is included

No resonant s-channel terms included because not enough information yet on couplings

* Oh, Kim; arxiv:0602112v4 (2006)Paul Mattione, Rice University


K+Σ(1385)- Predictions, LEPS Data Model based on effective Lagrangians Theory model by Oh, Ko, and Nakayama (Phys Rev C, 77 045204 (2008)) Data by Hicks, et al. (LEPS); arxiv:0812.0771v1 (2008) Haiyun Lu (eg3) – high energy, g13 – near-threshold energy



Jefferson Lab CEBAF & CLAS



Event Selection Same final state particles (p, K+, π-, π-) Λ, (p) Gaussians cut at 3σ



Interference in Eγ Bins 200 MeV Eγ Bins, 1.5 – 2.5 GeV

Negligible interference at Eγ < 1.9 GeV (K(892)*0Λ threshold ~1.65 GeV, minimum momentum cuts)



Interference Cut For Eγ > 1.9 GeV: Fit K(892)*0 and Σ(1385)- to Breit-Wigners,

interference cut at 80%



Signals Σ(1385)-

45707 Signal Events 16.3 Signal/Back Ratio PDG (MeV) 1387, 39.4

K(892)*0

Eγ > 1.9 GeV 6985 Signal Events 2.15 Signal/Back Ratio PDG (MeV) 896, 50.3



K(892)*0Λ Yield 200 MeV bins, background not subtracted Statistical errors only



K+Σ(1385)- Yield 200 MeV bins, background not subtracted Statistical errors only



Major Ongoing/Future Work

Measuring γD -> pπ-(p) cross section, compare to SAID Test of g13a data Understand detector inefficiencies

γD -> K(892)*0Λ(p) and γD -> K+Σ(1385)-(p) cross sections Finalize acceptance correction Sideband subtraction underneath signal peaks Systematic error studies



Advisors: Dan Carman, Jefferson Lab Paul Padley , Rice University

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