Saheli Rakshit | Search arXiv

arXiv2026

Transition Radiation Detector Upgrade for the GlueX-III Charmonium Program

The GlueX-III experiment at Jefferson Lab, planned to run in 2027-2029, will enhance the laboratory's capability to explore charmonium production near threshold and related aspects of QCD in the non-perturbative regime. A central upgrade for GlueX-III is a large-scale triple-GEM Transition Radiation Detector (TRD) optimized for electron identification and pion suppression in the hadron-rich environment of fixed-target photoproduction. This document describes the motivation for and efforts related to such an upgrade, including the design, construction, and performance of a 720x528mm$^{2}$ triple-GEM-TRD prototype that was tested in the existing GlueX-II experimental acceptance during the 2025 run. Results validate the prototype's integration, timing performance, and electron identification capability. Its projected impact in the GlueX-III setting is discussed, with background reduction in a $J/ψ$ candidate sample demonstrated. The development and use of a modern TRD technology in a high-background environment at Jefferson Lab may inform detector design choices as a future upgrade path for the EIC.

physics.ins-det↗

arXiv2021

Radiative M1 transitions of heavy baryons: Effective Quark Mass Scheme

We calculate the magnetic moments of ground state $J^P=\frac{1}{2}^+$ and $J^P=\frac{3}{2}^+$ heavy flavor charm and bottom baryon states employing the concept of effective mass based on single gluon exchange interaction coupling to the spectator quarks in the non-relativistic quark model. We exploit the current experimental information in the heavy flavor sector to estimate the interaction contributions to get the effective masses of the quarks inside the baryons. We study the spin $\frac{1}{2}^{'+} \rightarrow \frac{1}{2}^+$, $\frac{3}{2}^+ \rightarrow \frac{1}{2}^+$, and $\frac{3}{2}^+ \rightarrow \frac{1}{2}^{'+}$ transition moments for these baryons. We make robust predictions of the radiative M1 decay widths of singly, doubly, and triply heavy flavored baryons.

hep-ph↗