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 Mondays at 11:00 am (remote only)

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

May 13, 2024

Agenda
- Simulation Update (Lucas)
- LAD bar update
- Other updates

April 08, 2024

Agenda
- GEM update (Lucas, Holly)
- LAD bar and fiber update (Carlos, Sara, Florian)
- EPJA Referee Report
- Other updates

January 29, 2024

Agenda:
- Software update (Carlos)
- GEM update (Holly) and simulations (Lucas, Tyler)
- Laser system update (Florian)
  - Fibers arrived, variable optical attenuator arrived, still waiting on signatures on property passes (reminder email sent to people who can sign)
  - Patch panels for fibers will be made by Tel Aviv - need to sent Eli/Igor specs and how many we need.
- LAD testing and fiber installation (Florian)
  - Updated ESB setup [1], safety documents done but need to weigh one bar for lifting regulations - probably tomorrow.
- Target (Florian)
  - Request by Dave on specs on in-plane and out-of-plane opening angles to design the cut-off on the target holder at large angles.

January 22, 2024

Agenda:
- Meetings now every week!!
- 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

January 10, 2024

Agenda:
- Software update (Carlos)
  - some bars in geant, developed plan with Sangwha on the software integration into HallC reconstruction software.
  - discussion on how to best simulate data and test with new reconstruction software. Could also use pseudo-date from other HallC hodoscopes similar to what NPS did.
- GEM update (Holly) and simulations (Lucas, Tyler)
  - Simulations results for GEMs by next week.
  - GEM under HV next week. Setting up in stand soon
- Laser system - no update:
- Plans for next month (Florian)
  - Update ESB setup and get safety documents ready
  - Finish simulations of UITF testing
  - Complete simulation detectors
- New meeting time is now Mondays at 11am

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

Pre-Run Task List

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:

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