Differential Cross Section Measurements for $\gamma n\to {\pi }^{-}p$ Above the First Nucleon Resonance Region

Abstract

The quasi-free $\gamma d\to {\pi }^{-}p(p)$ differential cross section has been measured with CLAS at photon beam energies $E_{\gamma }$ from 0.445 GeV to 2.510 GeV (corresponding to $W$ from 1.311 GeV to 2.366 GeV) for pion center-of-mass angles $\cos {\theta }_{\pi }^{c.m.}$ from -0.72 to 0.92. A correction for final state interactions has been applied to this data to extract the $\gamma n\to {\pi }^{-}p$ differential cross sections. These cross sections are quoted in 8428 $(E_{\gamma },\cos {\theta }_{\pi }^{c.m.})$ bins, a factor of nearly three 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 $N^{\ast }$ resonances and extract their properties. Selected photon decay amplitudes $N^{\ast }\to \gamma n$ at the resonance poles are determined for the first time and are reported here.

References in corpus (7)

• Unitary Isobar Model - MAID2007
• Extended Partial-Wave Analysis of piN Scattering Data
• Updated analysis of NN elastic scattering to 3 GeV
• Eta photoproduction in a combined analysis of pion- and photon-induced reactions
• Pole positions and residues from pion photoproduction using the Laurent+Pietarinen expansion method
• Beam asymmetry $\Sigma$ measurements on the ${\pi }^{-}$ photoproduction off neutrons
• Legendre Analysis of Differential Distributions in Hadronic Reactions

Cited by in corpus (6)

• Light Baryon Spectroscopy
• Nucleon resonance production in the $\gamma p\to p\eta \varphi$ reaction
• High Energy Behaviour of Light Meson Photoproduction
• Pseudoscalar and Scalar Meson Photoproduction Interpreted by Regge Phenomenology
• Single ${\pi }^0$ Production Off Neutrons Bound in Deuteron with Linearly Polarized Photons
• New graphical criterion for the selection of complete sets of polarization observables and its application to single-meson photoproduction as well as electroproduction