Baby BCAL at JLab

This page is intended to summarize JLab work with the baby BCAL in 2023 for the EPIC (EIC) Barrel EM Calorimeter 

Note that we agreed to use the name "Baby BCAL" in June 2023. Previously one may encounter use of the name "mini BCAL" as well.

Photos & Sketches

• See photo page here

March 2023 Beam Tests

Goals and Hall D PS Setup

Main Goals

1. Demonstrate the Baby BCAL setup works
2. Measure resolution at 3-6 GeV to better constrain the constant portion of resolution function
3. Extract number of photoelectrons/GeV with well understood beam conditions

Pre-Beam

• Slides for EPIC Describing Plans
• Equipment checks in EEL Building

Logbook Entries

• First look at mini BCAL data (3/7/23)
• Repositioning of SciGlass (3/18/23)
• Repositioning of mini BCAL and raw mode run log (3/19/23)
• Quick sketch of final mini BCAL position (3/28/23)

Notable Configuration Changes

(not necessarily complete)

• Good runs start at 121050. There may be issues with data quality earlier on. Energy coverage: roughly 3.2-4.5 GeV and 5.6-5.9 GeV.
• SciGlass moved: 121197 and after. Energy coverage: roughly 3.2 - 5.2 GeV.
• BBCAL rotated runs 121210 and after
• SiPM biases:
  • From logbook entries, these probably need to be double checked
  • 75 upstream, 74 V downstream 121050-121209
  • 75 upstream, 73.5 V downstream 121210
  • 75.5 upstream, 74 V downstream 121211
  • 75 upstream, 73.5 V downstream 121212-end

Run Log

• Raw Mode:
  • Run 121209 (75 and 73.5 V SiPM bias)
  • Run 121210 (75.5 and 74 V SiPM bias)
  • Runs 121208, 121213 and 121215 are also raw mode config according to RCDB, but no notes on BBCAL config found in logbooks.

Cosmic Tests, started August 2023

Configuration

We attempted to use as close to the same configuration as in March 2023 as possible. Below is a list of cabling and configurations.

Note: North=Downstream, South=Upstream. These are now arbitrary labels. Downstream/north is located closer to the collimator cave, and upstream/south is located closer to the solenoid.

Photos (Google Drive)

See here: https://drive.google.com/drive/u/0/folders/10gY_D79DA5fxd1jLWmTN1qT_IqnvnW6d

SiPM Modules

• Used upstream & downstream modules 49 in their corresponding up/down sides (as labeled on baby BCAL)
  • Upstream module plugged into J7, downstream into J8 to match March 2023 config.
  • Standard LV=5 V setting for low voltage power to modules
  • Upstream bias voltage = 75 V, downstream bias voltage = 74 V (to match start of March 2023 conditions). See logbook entry for later voltage settings: https://logbooks.jlab.org/entry/4151946.
  • Scripts to turn bias and LV on/off can be found on gluon machines at: /gluonfs1/home/hdops/bcal_cosmic/august2023/
• Cabling: same as March 2023. Lemo cables labeled AS0-AS15 and AN0-AN15. These are plugged into crate U1-7-TOP (crate number 94 in software). Slot 7 is north, slot 8 is south (indexes 0-15 in slot match A(S/N)0-15).

Analysis - Sasha/Karthik/Zisis

• Directories for Baby BCAL Cosmics Analysis: (on hdops)
  • /gluonfs1/home/hdops/bbcal with 2 subdirectories:
  • glass_prototype: code to make ROOT files for cosmics analysis; use DEventProcessor_fcal_hists.cc (in this dir)
  • display: code to parse through events and saw raw more pulses; use DEventProcessor_fcal_hists.cc (in this dir)
• Command for environment: source setenv.csh / see setenv HALLD_MY ..display under HDDS section of setenv.csh and the very last line of that file which has source /gluex/etc/hdonline.cshrc; Sasha used those two to nail the ENV variables
• Commands for building: scons -c / scons -u install
• Command for analyzing: hd_root -PPLUGINS=glass_prototype -o bbcal.root /gluonraid5/data4/rawdata/active/RunPeriod-2023-01/rawdata/Run121303/*.evio
• ROOT tree: contains raw amp_n, pulsed pulse_int_n, pulse_amp_n, pulse_ped_n, and ch_n, t_n. n is 1-16 for North, and 17-32 for South.
• Analysis needs more checking as not all results make sense (comment as of Sept 28, 2023, by ZP).

Analysis - Jon's

• Analysis plugin on JLab farm: /home/jzarling/work/HALLD_MY/miniBCAL_EIC/ and /work/HALLD_MY/miniBCAL_EIC_RawMode/
• Analysis plugin on gluon machines: /gluonfs1/home/hdops/bcal_cosmic/babyBCAL_EIC
• Occupancy check:
  • Assuming you are logged onto a gluon machine (or anywhere behind JLab's firewall hallgw) do:
  • ssh hdops@gluon47
  • cd /gluonfs1/home/hdops/bcal_cosmic/babyBCAL_EIC
  • Use script run_on_testfile and run number (e.g. ./run_on_testfile 121302 in the same folder as the plugin. This will run the plugin and create two png files in the same directory with occupancies for each channel.
• First Look at Calibrated BCAL