PS acceptance and luminosity determination
Pair Spectrometer acceptances were measured using runs with the total absorption counter. The shapes were compared with the detailed Geant simulation.
The normalization of PS acceptances agrees reasonably well, on the level of 5%, for 2018, 2017, and 2016 TAC runs. Note, the acceptance shape for 2016 data
is different due to the larger PS magnetic field. A good agreement in shapes between the measurements and simulation was observed.
Presentations on TAC measurements
Comparison of the refined acceptance of 2016, new acceptance of 2017
Preliminary determination of the PS acceptances in 2016
TAC run, half of the field, Nov 7, 2018
Instructions to obtaining measured fluxes from CCDB
A Python script plot_flux_ccdb.py located in hd_utilities will create a ROOT histogram of the PS tagged flux for a given range of runs. The energy binning of the histogram can be modified with some command line parameters in the README file (below).
More detailed instructions are provided in the $README on GitHub. On the ifarm you can setup your environment using the nightly build (example below), or your favorite environment setup script to set the CCDB and RCDB context.
source /group/halld/Software/build_scripts/gluex_env_nightly.csh 2018-11-01
With your environment set you can run the command to create the flux histogram from the database with the command below
python /group/halld/Software/hd_utilities/plot_flux_ccdb.py -b beginRun -e endRun
