Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab

M.E. Mccracken , M. Bellis , C.A. Meyer , M. Williams , K.P. Adhikari , M. Anghinolfi , J. Ball (1) , M. Battaglieri , B.L. Berman , A.S. Biselli , D. Branford , W.J. Briscoe , W.K. Brooks , V.D. Burkert , S.L. Careccia , D.S. Carman , P.L. Cole , P. Collins , V. Crede , A. d'Angelo , A. Daniel , N. Dashyan , R. de Vita , E. de Sanctis , A. Deur , B. Dey , S. Dhamija , R. Dickson , C. Djalali , D. Doughty , M. Dugger , R. Dupre , A. El Alaoui , P. Eugenio , S. Fegan , A. Fradi (2) , M.Y. Gabrielyan , K.L. Giovanetti , F.X. Girod (1) , J.T. Goetz , W. Gohn , R.W. Gothe , K.A. Griffioen , M. Guidal (2) , K. Hafidi , H. Hakobyan , C. Hanretty , N. Hassall , K. Hicks , M. Holtrop , Y. Ilieva , D.G. Ireland , H.S. Jo (2) , D. Keller , M. Khandaker , P. Khetarpal , W. Kim , A. Klein , F.J. Klein , V. Kubarovsky , S.V. Kuleshov , V. Kuznetsov , K. Livingston , M. Mayer , J. Mcandrew , B. Mckinnon , M.D. Mestayer , T. Mineeva , M. Mirazita , V. Mokeev , B. Moreno (1) , K. Moriya , B. Morrison , H. Moutarde (1) , E. Munevar , P. Nadel-Turonski , S. Niccolai (2) , G. Niculescu , I. Niculescu , M. Osipenko , A.I. Ostrovidov , K. Park , S. Park , E. Pasyuk , S. Anefalos Pereira , Y. Perrin (3) , S. Pisano (2) , O. Pogorelko , S. Pozdniakov , J.W. Price , S. Procureur (1) , Y. Prok , D. Protopopescu , B. Quinn , B.A. Raue , G. Ricco , M. Ripani , B.G. Ritchie , G. Rosner , P. Rossi , F. Sabatié (1) , M.S. Saini , J. Salamanca , D. Schott , R.A. Schumacher , E. Seder , H. Seraydaryan , Y.G. Sharabian , D.I. Sober , D. Sokhan , S.S. Stepanyan , P. Stoler , S. Strauch , M. Taiuti , D.J. Tedeschi , S. Tkachenko , M. Ungaro , B. Vernarsky , M.F. Vineyard , D. Watts , E. Voutier (3) , L.B. Weinstein , D.P. Weygand , M.H. Wood , L. Zana

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
2 IPNO - Institut de Physique Nucléaire d'Orsay
3 LPSC - Laboratoire de Physique Subatomique et de Cosmologie

We present measurements of the differential cross section and Lambda recoil polarization for the gamma p to K+ Lambda reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ p pi- and K+ p (missing pi -) final-state topologies; results from these analyses were found to exhibit good agreement. These differential cross section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300 MeV increase in energy coverage. The recoil polarization data agree well with previous results and offer a large increase in precision and a 500 MeV extension in energy range. The increased center-of-mass energy range that these data represent will allow for independent study of non-resonant K+ Lambda photoproduction mechanisms at all production angles.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

M.E. Mccracken, M. Bellis, C.A. Meyer, M. Williams, K.P. Adhikari, et al.. Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab. Physical Review C, 2010, 81, pp.025201. ⟨10.1103/PhysRevC.81.025201⟩. ⟨in2p3-00470352⟩