Photocathodes fabricated with a distributed Bragg reflector have been known to provide higher quantum efficiency, because the light entering the photocathode can reflect many times between the DBR and the front surface of the photocathode, providing more absorption of the incident laser light. Our team previously demonstrated enhanced quantum efficiency from a DBR photocathode using the...
Introduction
Nuclear spin hyperpolarization (HP) enhances the NMR signal by several orders of magnitude by bringing the spins out of thermal equilibrium, populating one of the spin states in favor of the other. Enhanced spin polarization is especially advantageous at ultra-low magnetic field strengths, where thermal polarization may often result in NMR signal intensities that are...
Using a simple smooth step like function of emittance developed from direct spin-orbit tracking simulations, we characterize the polarization performance from previous RHIC runs.
Normalizing Flows have been implemented across several fields, notably in image generation and recently high energy and nuclear physics. The present study investigates the ability of flow based neural networks to improve signal extraction of Λ Hyperons at CLAS12. Normalizing Flows enable density estimation by learning how to transform a simple distribution with a known PDF to a complex...
The 1+1D model of quantum chromodynamics (QCD) in the infinite number of colors, or ‘t Hooft model, is interpolated between the instant form dynamics (IFD) and the light-front dynamics (LFD) using an interpolation parameter δ in the interpolating Coulomb gauge which links the Coulomb gauge (A⁰ = 0) in IFD and the light-front gauge (A+ = 0). While calculations such as these were performed [1]...
The use of an intense ultrashort laser pulse to induce electron polarization has been proposed in existing literature[1]. Utilizing the Python programming language, a code has been developed to recreate the local constant crossed-field approximation (LCFA) with the aim of determining values for transverse polarization given a nonzero initial polarization. It has been shown that over multiple...
This contribution will show projections of transverse single spin asymmetries sensitive to transversity that can be measured with the ePIC detector at the future EIC
The upcoming K-Long experiment [1] ain Hall D at Jefferson Lab presents unique beam requirements, featuring a significantly low bunch repetition rate and an unusually high bunch charge. This experiment, which utilizes the CEBAF accelerator in conjunction with the GlueX experimental setup, aims to study strange hadron spectroscopy by measuring the differential cross section and polarizations of...
The sPHENIX experiment, currently in commissioning at the Relativistic Heavy Ion Collider at BNL, is a new detector built for jet, direct photon, and hadron measurements. Next year, sPHENIX will take data from transversely polarized p+p and p+Au collisions. Transverse single spin asymmetry (TSSA) measurements at sPHENIX from the 2024 run will explore the parton dynamics within transversely...
The propagation properties of spin degrees of freedom are analyzed in the framework of relativistic hydrodynamics with spin based on the de Groot van Leeuwen–van Weert definitions of the energy-momentum and spin tensors. We derive the analytical expression for the spin wave velocity for arbitrary statistics and show that it goes to half the speed of light in the ultrarelativistic limit. We...
We extend the classical phase-space distribution function to include the spin and electromagnetic fields coupling and derive the modified constitutive relations for charge current, energy-momentum tensor, and spin tensor. Because of the coupling, the new tensors receive corrections to their perfect fluid counterparts and make the background and spin fluid equations of motion communicate with...
The COMPASS experiment took data between 2000 and 2022 using the SPS muon and hadron beams in the CERN North Area and fixed unpolarized and polarized nuclear targets. It remains one of the most impactful experiments in the field due to its contributions in exploring the spin structure of the nucleon. One of the key objectives of COMPASS is to investigate transverse momentum dependent PDFs by...
Novel improvements to small-$x$ helicity evolution equations have been incorporated into a global analysis of both DIS and SIDIS cross sections. This global analysis uncovered a bimodality of solutions for the asymptotic ($x \to 0 $) sign of the $g_1$ structure function of the proton, and a novel correlation it has with the quark and gluon helicity parton distribution functions (hPDFs),...
The sPHENIX experiment is a new detector at BNL's Relativistic Heavy Ion Collider. Designed for studies of the quark-gluon plasma produced in heavy ion collisions with high-pT jet and heavy flavor probes, sPHENIX will also enable an array of cold QCD measurements in polarized p+p and p+Au collisions. The measurements of transverse spin asymmetries in the production of photons, mesons, and jets...
The polarization of the $\Lambda$ hyperon is a key observable in the study of the Quark-Gluon Plasma produced in heavy ion collisions. Recent studies have highlighted the importance of considering the thermal shear tensor, the symmetric derivative of the four-temperature vector, in the calculations of polarization as it can accommodate the discrepancy between theoretical predictions and...
During collisions between leptons and transversely polarized nucleons at high energy, the left-right asymmetric formation of hadrons can be probed. These so-called transverse single-spin asymmetries AN are the subject of our work. One issue for lower-energy fixed-target experiments is the possible need for next-to-leading order (NLO) corrections. Therefore, to create plausible predictions of...
