GEM Detectors for DarkLight Phase I

Graduate #89
Discipline: Physics
Subcategory: Physics (not Nanoscience)

Sahara Jesmin Mohammed Prem Nazeer - Hampton University

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The DarkLight experiment has been proposed to search for a heavy photon A’ in the mass range of 10-100 MeV/c^2 produced in electron scattering. Phase 1A of DarkLight has started to take place in 2016 at the Low Energy Recirculator Facility (LERF) at Jefferson Lab. LERF delivered a 100 MeV electron beam onto a windowless hydrogen gas target. The Phase-Ia detector tracks leptons inside the DarkLight solenoid with a set of Gas Electron Multiplier (GEM) detectors, combined with segmented scintillators for triggering. The GEM telescope consists of four 10×10 cm^2 triple layer GEM chambers with 2D readout strips, mounted in a slightly angled fixed frame about 12 cm tall.
For Phase 1C a setup of two magnetic spectrometers is designed for a targeted search for a dark photon in the mass region near 17 MeV/c^2 where a signal was recently reported by a Hungarian group, interpreted as a fifth force particle. The group is developing customized GEM detectors to instrument the Phase-1C setup with a tracking detector system for the electron positron pair originating from the decay of the A’.
The performance of the 10×10 GEM telescope will be discussed, with a status update of the preparation of the Phase 1C detector.

Abstract-ERN.docx

Funder Acknowledgement(s): This work is supported by NSF grants PHY-1505934 and PHY-1436680.

Faculty Advisor: Michael Kohl, kohlm@jlab.org

Role: The re-assembling of GEM detectors for the DarkLight experiment, testing, installing and data analysis for the phase 1A. Designing of the phase 1C detector will be done.