Summary Winter 2024 Run
RC Summary, March 2024 Test Run (A. Deur)
The March 2024 test run took place from March 12 to March 15. Its objective was to test a GEM-TRD detector, along with other GEM detectors, and to inspect the beam line following a year of downtime. The test proved to be highly successful, with detailed information provided on the run page: https://halldweb.jlab.org/wiki/index.php/Run_Coordination_Meetings:Winter2024
Beam arrival was scheduled for March 12 (Monday) afternoon, but usable beam (not requiring photon polarization for this test) became available on March 13 around 5:20 am. Beamline and beam quality checks were performed without any major issues. The primary challenge encountered was a poorly responsive motor driving the amorphous radiator ladder and our harp. Although not a showstopper, it was opportunistically fixed during downtime with a simple lubrication. Photon beam transmission to the hall was satisfactory, with a rate of about 5 kHz in the PSC counters compared to the expected 8.7 kHz for optimal, converging beam (100 nA, 2×10^-5 RL 750 μm TPOL converter). Testing and optimization of the GEM-TRD commenced, utilizing Ar gas in the detector.
On March 13th, accelerator maintenance took place from 7 am to 9 pm, with Hall D beam resuming only on the 14th at 1:30 am. During this downtime, the gas was changed from Ar to Kr. Testing of the GEM-TRD proceeded smoothly, with numerous rapid accesses for transition radiator configuration changes. Initially, it was anticipated that the beam would be terminated on the 15th (Friday) at 7 am. However, delays in the readiness of Hall B (from which beam we were utilizing) permitted us to run until mid-Saturday if necessary. Nevertheless, by the conclusion of Friday, our program objectives had been achieved, and we requested MCC to terminate the beam. The radiator was retracted, and the collimator was positioned to block beam. The PS and sweeping magnets were ramped down, and the Hall along with the tagger were set into "Power Permit" mode for the weekend.
In total, we had 88 hours scheduled, were operational for 53.5 hours, and received 50 hours of ABU and 9.8 hours of BANU.
