A New Measurement of Beam Asymmetry in Pion Photoproduction from the Neutron Using Clas
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چکیده
We present a preliminary analysis of the photon beam asymmetry observable (Σ) from the photoproduction reaction channel γn → π−p. This new data was obtained using the near-4π CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 2.3 GeV. The measurement will provide new data to address the poorly established neutron excitation spectrum and will greatly expand the sparse world data-set both in energy and angle.
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تاریخ انتشار 2008