LAD wiki

LAD Overview

The LAD experiment is set to run in Hall C in September 2024. 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.

LAD Task Force Contact

Name	e-mail
Florian Hauenstein	hauenst@jlab.org
Holly Szumila-Vance	hszumila@jlab.org
Larry Weinstein	lweinste@odu.edu
Carlos Ayerbe Gayoso	gayoso@jlab.org

Our mailing list is lad_hallc@jlab.org

Weekly Meeting Information

Weekly Meetings are Tuesdays at 09:15 am (remote only)

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

January 10, 2024

• Agenda:
  • Software update (Carlos)
    • some bars in geant —> next step is to complete all bars and combine with GEMs from SBS
  • GEM update (Holly) and simulations (Lucas, Tyler)
    • tomorrow put GEMs on stands
    • simulation results: with 200keV beam energy get about 100kHz/cm2 from their simulations at 1uA beam on radiator (that is pretty low than what we wanted to have)
    • discussion about what we can change: radiator material or width, also check with expert from accelerator
  • Laser system update:
    • fibers here soon as well as variable attenuator
    • no update from splitter until end of January
    • issue propery pass for laser system components, afterwards move laser system components to odu (maybe this week?)
  • Plans for next month (Florian)
    • Update ESB setup and get safety documents ready
    • Install fibers
    • Complete simulation detectors

November 28 , 2023

• Agenda:
  • GEM update (Holly)
    • Holly talked Matt Poelker at Jlab. We could get a beam of up to 100keV photons at UITF at Jlab to test the PRAD gems before and after the upgrades with an Aluminum foil for charge deposition. We will get some simulations about the photon distributions
    • Faraday shielding design to do
    • Test early to mid January
  • Laser system update (Florian)
    • Everything is on order, fibers to be expected mid-January, laser at Tel-Aviv airport -> rerouted to fiber splitter company. Testing at the splitter company some time in January.
  • Bar testing - Dark currents (Carlos)

October 17 , 2023

• Agenda:
  • LAD bar testing update
    • Sara presented initial checks on LAD PMTs ~35% have issues. Sara presentation
  • Laser system update
    • Or agreed to pay some stuff for the laser system (amazon and thorlabs) or signal generator.
    • Other items will be ordered soon.
  • GEM Update
    • GEM is under gas since weeks, GEM HV will be tested in the afternoon, some confusion about flow rate - some discussion with UVA, 8000cm3 volume of a chamber. at the moment about 3 volume changes per hour -> maybe should be increased.

October 3, 2023

• Agenda:
  • LAD bars update
    • Testing started. Some PMTs were already found non functioning
  • Laser system update
    • Splitter has 14-16 weeks lead time. Laser will be shipped directly to the company.
    • No update on the order of the other components
  • Draft workplan
  • General LAD Hall layout

September 19, 2023

• Laser system:
  • Axel need to talk with splitter company and Eli for details about shipping laser to them
  • Florian need to order fibers and small components (purchase order with the lab)
• Holly is back and starts working on the GEMs
• Setup of LAD bar testing in EEL in progress

September 05, 2023

• New meeting time now 9:15 Tuesdays
• Agenda and Discussions items
• Discussion about the details of the Laser system equipment and open software tasks

LAD Simulation

• More info here when work progresses

LAD Running

LAD Preparation Workplan

• Draft

LAD Commissioning and production run plan

• • Add here the preliminary plan from the ERR

Targets on ladder: Hall C Target Ladder

• Planned targets:
  • D, H, dummy, optics

LAD Trigger Set-Up

The LAD experiment will detect electrons in the SHMS and HMS with recoil protons passing through the GEMs and scintillators.

Tentative LAD Trigger Configuration:
SHMS:
HMS:
COIN:

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

LAD Trigger Checkout:

LAD Cerenkov Gas Mixture

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

• Hall C Cherenkovs ERR 2016
• SHMS PMT ET9823 B Series
• SHMS NGC Preliminary Report

LAD Bars Documents

• Testing in ESB 2023

• ODU Senior Theses:
  • James Porter, May 10, 2014: Thesis
  • Sonja Schimmers, Aug 20, 2015: Thesis
  • Juan Rodriguez, August, 2017: Thesis
• CLAS6 TOF NIM paper: File

Proposals and ERR

• LAD ERR
• LAD original proposal E12-11-10