The quasifree gamma d -> pi(-)p(p) differential cross section has been measured with CLAS at photon beam energies E-gamma from 0.445 to 2.510 GeV (corresponding to W from 1.311 to 2.366 GeV) for pion center-of-mass angles cos theta(c.m.)(pi) from -0.72 to 0.92. A correction for final state interactions has been applied to these data to extract the gamma n -> pi(-)p differential cross sections. These cross sections are quoted in 8428 (E-gamma, cos theta(c.m)(pi)) bins, a factor of nearly 3 increase in the world statistics for this channel in this kinematic range. These new data help to constrain coupled-channel analysis fits used to disentangle the spectrum of N* resonances and extract their properties. Selected photon decay amplitudes N* -> gamma n at the resonance poles are determined for the first time and are reported here.
Mattione, P.t., Carman, D.s., Strakovsky, I.i., Workman, R.l., Kudryavtsev, A.e., Svarc, A., et al. (2017). Differential cross section measurements for γn→π-p above the first nucleon resonance region. PHYSICAL REVIEW C, 96(3), 035204-1-035204-20 [10.1103/PhysRevC.96.035204].
Differential cross section measurements for γn→π-p above the first nucleon resonance region
D'Angelo A.Membro del Collaboration Group
;Lanza L.;Pisano S.;Rizzo A.;
2017-09-18
Abstract
The quasifree gamma d -> pi(-)p(p) differential cross section has been measured with CLAS at photon beam energies E-gamma from 0.445 to 2.510 GeV (corresponding to W from 1.311 to 2.366 GeV) for pion center-of-mass angles cos theta(c.m.)(pi) from -0.72 to 0.92. A correction for final state interactions has been applied to these data to extract the gamma n -> pi(-)p differential cross sections. These cross sections are quoted in 8428 (E-gamma, cos theta(c.m)(pi)) bins, a factor of nearly 3 increase in the world statistics for this channel in this kinematic range. These new data help to constrain coupled-channel analysis fits used to disentangle the spectrum of N* resonances and extract their properties. Selected photon decay amplitudes N* -> gamma n at the resonance poles are determined for the first time and are reported here.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
