Undergraduate Research at Jefferson Lab

Modeling and Instrumentation of a Beam Dump Compton Transmission Polarimeter

Student: Dalia Lucero Ramírez Guadarrama

School: Autonomous National University of Mexico

Mentored By: Joseph Grames

At the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory, polarized electrons are generated and accelerated to 12 GeV to probe nuclear interactions. There are many ways to measure electron polarization, but an alternative novel idea is to use the beam dump of a Mott polarimeter which is installed along the beam line, making electrons interact with the beam dump and studying the radiation produced with a magnetized iron target. The transmission rate asymmetries are measured as a function of the beam helicity and the target magnetization. Simulations of the apparatus were also made with GEANT4, and the energy distribution of the electrons reaching the detector were simulated with and without the magnetized iron target. These simulations gives a more realistic idea of the interactions taking place in the beam dump and in the target. We can now make a quick measurement of electron beam polarization without using the Mott, and without complicated Wien filter setups, which takes time to implement.