Undergraduate Research at Jefferson Lab

Measurement of Single Spin Asymmetries in Proton Electroproduction

Student: Devin O'Neill

School: Duquesne University

Mentored By: Dr. Harut Avagyan

Jefferson Lab is equipped with the Continuous Electron Beam Accelerator Facility (CEBAF.). A 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF was aimed at a target of unpolarized protons in Hall B. The CLAS12 spectrometer allows the detection of hadrons resulting from the Semi-Inclusive Deep Inelastic Scattering (SIDIS) process and the analysis of this data allows access to the beam single spin asymmetries for different hadron species. The study of single spin asymmetry will allow us to investigate into the proton constituents, understand how quarks and antiquarks are distributed within the proton, and allow for the expansion of human understanding regarding nuclear structure. We focused on analyzing the kinematical and physical variables of the ep → e'p' channel towards the extraction of the azimuthal angular dependency of the beam single spin asymmetry for the detected protons. The data used for the variables is from Fall 2018. Results of this asymmetry are presented against key variables of this reaction using ROOT to produce histograms, 2-D plots, and 3-D plots. The initial results show that the beam spin asymmetry is non-zero for the proton channel, and such a non-zero value will give more information on the makeup of the proton.

[Watch the presentation on YouTube]