Data Analysis Techniques, Differential Cross Sections, and Spin Density Matrix Elements for the Reaction Gamma p -> phi p
High-statistics measurements of differential cross sections and spin density matrix elements for the reaction γp → ϕp have been made using the CLAS detector at Jefferson Lab. We cover center-of-mass energies (√s) from 1.97 to 2.84 GeV, with an extensive coverage in the ϕ production angle. The high statistics of the data sample made it necessary to carefully account for the interplay between the ϕ natural lineshape and effects of the detector resolution, that are found to be comparable in magnitude. We study both the charged- (ϕ → K+K-) and neutral- (ϕ → K[0 over S]K[0 over L]) K[⎯⎯⎯ over K] decay modes of the ϕ. Further, for the charged mode, we differentiate between the cases where the final K- track is directly detected or its momentum reconstructed as the total missing momentum in the event. The two charged-mode topologies and the neutral-mode have different resolutions and are calibrated against each other. Extensive usage is made of kinematic fitting to improve the reconstructed ϕ mass resolution. Our final results are reported in 10- and mostly 30-MeV-wide √s bins for the charged- and the neutral-modes, respectively. Possible effects from K+Λ* channels with pK[⎯⎯⎯ over K] final states are discussed. These present results constitute the most precise and extensive ϕ photoproduction measurements to date and in conjunction with the ω photoproduction results recently published by CLAS, will greatly improve our understanding of low energy vector meson photoproduction.
- Author (aut): Dey, B.
- Author (aut): Meyer, C. A.
- Author (aut): Bellis, M.
- Author (aut): Williams, M.
- Author (aut): Adhikari, K. P.
- Author (aut): Adikaram, D.
- Author (aut): Aghasyan, M.
- Author (aut): Amaryan, M. J.
- Author (aut): Anderson, M. D.
- Author (aut): Pereira, S. Anefalos
- Author (aut): Ball, J.
- Author (aut): Baltzell, N. A.
- Author (aut): Battaglieri, M.
- Author (aut): Bedlinskiy, I.
- Author (aut): Biselli, A. S.
- Author (aut): Bono, J.
- Author (aut): Boiarinov, S.
- Author (aut): Briscoe, W. J.
- Author (aut): Brooks, W. K.
- Author (aut): Burkert, V. D.
- Author (aut): Carman, D. S.
- Author (aut): Celentano, A.
- Author (aut): Chandavar, S.
- Author (aut): Colaneri, L.
- Author (aut): Cole, P. L.
- Author (aut): Contalbrigo, M.
- Author (aut): Cortes, O.
- Author (aut): Crede, V.
- Author (aut): D'Angelo, A.
- Author (aut): Dashyan, N.
- Author (aut): De Vita, R.
- Author (aut): De Sanctis, E.
- Author (aut): Deur, A.
- Author (aut): Djalali, C.
- Author (aut): Doughty, D.
- Author (aut): Dugger, Michael
- Author (aut): Pasyuk, Eugene
- Author (aut): Ritchie, Barry
- Author (aut): Senderovich, Igor
- Contributor (ctb): College of Liberal Arts and Sciences