Title: Hard exclusive $$\pi^{+}n$$ electro production beam spin asymmetries off the proton in the GPD and TDA regimes

Abstract

Hard exclusive \pi^{+} ${\pi }^{+}$ n electro-production can be used to gain access to the 3D nucleon structure. The QCD factorisation mechanism in the “nearly forward region” ( t/Q^{2} $t/Q^2$ small) allows a description by Generalized Parton Distributions (GPDs), while for the “nearly backward” kinematic region ( u/Q^{2} $u/Q^2$ small) a description based on nucleon to pion transitions (TDAs) is available. The paper presents a measurement of single beam spin asymmetries to extract the A^{\sin\phi}_{LU} $A_{LU}^{sin\varphi }$ moments and the related cross section ratio \sigma_{LT^\prime}/\sigma_{0} ${\sigma }_{L{T}^{\prime }}/{\sigma }_0$ from the hard exclusive \pi^{+} ${\pi }^{+}$ channel off the unpolarized hydrogen target in a wide range of kinematics based on data taken with the CLAS spectrometer at Jefferson Lab. In addition, under forward angles a detailed multidimensional study will be presented based on CLAS12 data and compared to theoretical predictions.

Authors:

Diehl, Stefan ^[1]

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+ Show Author Affiliations

1. University of Giessen, University of Connecticut

Publication Date:

Tue Jul 12 00:00:00 EDT 2022

Sponsoring Org.:

USDOE

OSTI Identifier:

1875722

Grant/Contract Number:  

AC05-06OR23177

Resource Type:

Published Article

Journal Name:

SciPost Physics Proceedings

Additional Journal Information:

Journal Name: SciPost Physics Proceedings Journal Issue: 8; Journal ID: ISSN 2666-4003

Publisher:

Stichting SciPost

Country of Publication:

Netherlands

Language:

English