CaFe Preparation

CaFe Preparation Overview

The CaFe experiment is set to run in Hall C in August 2022. This wiki will be used to document our weekly meetings, as well as post any other useful information such as proposals, previous publications, other useful links, etc. prior to the experiment running.

*CaFe Task Force Contact*
Name	e-mail
Dien Nguyen	dien@jlab.org
Holly Szumila-Vance	hszumila@jlab.org
Larry Weinstein	lweinste@odu.edu
Carlos Yero	cyero@jlab.org

Pre-Run Task List

CaFe Pre-Run Task List (google sheets)

*Targets currently on ladder: Hall C Target Ladder

Planned targets:
- D, H, dummy, optics
- Physics: 40Ca, 48Ca, 54Fe
- Next preference: 9Be, 10B, 11B, 12C
- If time: 48Ti
Planned Target Ladder for 2022-2023

Planned Targets for Run Period: 2022-2023 (D. Meekins, google spreadsheet)

Planned Targets for Run Period: 2022-2023 (D. Meekins, google spreadsheet) version 2

Updated CaFe Target Thickness

CaFe Solid Targets Spreadsheet - C. Yero updated Ca40,48, Fe54 Thickness on 09/24/22

D. Meekins Log-Entries on Hall C Fall 2022 Target Thickness Measurements

Hall C Solid Target Measurements Ca48 Target Fabrication

Targets Assay (assessment of element composition in targets)

Ca40_Assay_ORNL

Fe54_Assay_ORNL

Weekly Meeting Information

Weekly Meetings are Tuesdays at 09:30 am (remote only)
NOTE: This was usual meeting times pre-CaFe experiment. Now that we have finished the experiment, a new meeting time will be determined, mainly for analysis meetings with Noah.

Zoom remote connection information: https://jlab-org.zoomgov.com/j/1619420740?pwd=ZEZIVWNpYVpLdVFwWWRLcDBSY1pOQT09

Please add your presentation/updates or questions before each meeting under the appropriate (month, year) below

November 2021

December 2021

Monday, December 06, 2021

January 2022

CaFe SHMS NGC Gas Mixture

SHMS will detect e- momenta up to ~10.3 GeV/c, therefore if we want to use SHMS NGC for pion rejection, it will require ~ 90:10 Ne:Ar gas mixture for said momentum. The NGC gas mixture used so far has been: 60:40 Ne:Ar: https://logbooks.jlab.org/entry/3895288 , https://logbooks.jlab.org/entry/3938535

Documents related to the specific PMT type as well as photo-electron yields of the NGC can be found in the links below:

CaFe Trigger Set-Up

The CaFe experiment will detect electrons in SHMS and protons in HMS. The SHMS will be stationed at 8.55 GeV/c and range from ~6.8 deg to 8.3 deg, therefore the electron singles rates are expected to be significant. To minimize singles rates, it was decided to turn off half of the SHMS S1X and S2X hodoscope planes. To select a clean sample of electrons in SHMS, it was decided to 1) use SHMS EL-REAL trigger and 2) set the SHMS Noble Gas Cherenkov pion threshold to ~10.3 GeV/c (pion emits Cherenkov light at >= 10.3 GeV/c). During online data-taking we'll need to check how efficient is the Cherenkov at this configuration (~90% Neon, ~10% Argon). The latest trigger configuration from the previous run-group can be found in log-entry: https://logbooks.jlab.org/entry/3892668 The 3rd bullet point from the log-entry is IMPORTANT, since it suggests the pEL_REAL x h3/4 cable was terminated and left dangling in case we need it again, which we will during CaFe.

Tentative CaFe Trigger Configuration:
SHMS: EL-REAL (electron reals)
HMS: 3/4 Hodoscope Planes
COIN: SHMS EL-REAL x HMS 3/4

For trigger definitions, See Trigger Documentation: https://hallcweb.jlab.org/DocDB/0010/001028/005/trigger_v3.pdf

CaFe Trigger Checkout:

Hardware changes that need to be made during CaFe trigger checkout:

CaFe presentations

CaFe To-Do List

CaFe Pre-Run Task List (google sheets)

CaFe Preparation

Contents