Determination of the beam-spin asymmetry of deuteron photodisintegration in the energy regionEγ=1.1–2.3 GeV

A novel approach that allows access to long-sought information on the Hyperon-Nucleon (YN) interaction was developed by producing a hyperon beam within a few-body nuclear system, and studying final-state interactions. The determination of polarisation observables, and specifically the beam spin asymmetry, in exclusive reactions allows a detailed study of the various final-state interactions and provides us with the tools needed to isolate kinematic regimes where the YN interaction dominates. High-statistics data collected using the CLAS detector housed in Hall-B of the Thomas Jefferson laboratory allows us to obtain a large set of polarisation observables and place stringent constraints on the underlying dynamics of the YN interaction.

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The Tensor and the Scalar Charges of the Nucleon from Hadron Phenomenology

EPJ Web of Conferences ◽

10.1051/epjconf/201817203007 ◽

2018 ◽

Vol 172 ◽

pp. 03007

Author(s):

A. Courtoy

Keyword(s):

Standard Model ◽

Spin Asymmetry ◽

Beyond The Standard Model ◽

Scalar Charge ◽

The Standard Model ◽

Asymmetry Data ◽

Fragmentation Functions ◽

The Impact ◽

Beam Spin Asymmetry

We discuss the impact of the determination of the nucleon tensor charge on searches for physics Beyond the Standard Model. We also comment on the future extraction of the subleading-twist PDF e(x) from Jefferson Lab soon-to-be-released Beam Spin Asymmetry data as well as from the expected data of CLAS12 and SoLID, as the latter is related to the scalar charge. These analyses are possible through the phenomenology of Dihadron Fragmentation Functions related processes, which we report on here as well.

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Beam spin asymmetry for DeltaVCS

10.22323/1.077.0079 ◽

2012 ◽

Author(s):

Brahim Moreno

Keyword(s):

Spin Asymmetry ◽

Beam Spin Asymmetry

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Extraction of ALUsin(ϕ) moments from the hard exclusive π+ channel in a wide range of kinematics with CLAS

Journal of Physics Conference Series ◽

10.1088/1742-6596/1643/1/012187 ◽

2020 ◽

Vol 1643 (1) ◽

pp. 012187

Author(s):

Stefan Diehl ◽

Kyungseon Joo

Keyword(s):

Spin Asymmetry ◽

Smooth Transition ◽

Parton Distributions ◽

Generalized Parton Distributions ◽

Transition Distribution ◽

Clear Sign ◽

Sign Change ◽

Wide Range ◽

Large Acceptance ◽

Beam Spin Asymmetry

Abstract The beam-spin asymmetry (BSA) has been measured for the hard exclusive e p → e n π+ reaction over a wide range of kinematics in the deep inelastic regime. The measurements were performed with the CEBAF Large Acceptance Spectrometer (CLAS) using a 5.5 GeV polarized electron beam at Jefferson Lab (JLAB). The ϕ dependence of the BSA as well as the −t, Q 2 and xB dependence of the extracted ALU sin(ϕ) moment will be presented. For ALU sin(ϕ) a clear sign change can be observed between pions emitted in forward and backward direction with a smooth transition around 90° in CM. The results will be discussed in the context of formalisms depending on generalized parton distributions (GPDs) and transition distribution amplitudes (TDAs), which can be used to describe complementary kinematic regimes.

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