Difference between revisions of "He3 / H3 e,e'p experiment E12-14-011"

Revision as of 14:47, 30 May 2018

The SRC Tritium Experiment (E12-14-011) is an (e,e'p) experiment in Hall A, comparing the momentum distribution of protons in tritium and helium-3. These nuclei have a large proton-neutron asymmetry, but are also isospin-mirror nuclei, meaning that the proton distribution in tritium can tell us about the neutron distribution in helium-3.

During the experiment

The information that was more relevant for activities during the data-taking period will be moved from this page to the following new page:

• Data-taking period

Important Links

• Hall-A website
• Hall-A Elog
• Shift Sign-Up
• Shift Schedule (Read only)
• Run Coordinator Page
• CEBAF Status
• HRS info

Other information

• Kinematics MORE DETAILS HERE
  • Ebeam (nominal) = 4300 MeV
  • Ebeam (epics) = 4318.49 MeV

• BCM calibration
  • run number: 100172
  • target: carbon foil
  • currents and attenuator values:
    • 3uA ---> 140
    • 7uA ---> 163
    • 12uA ---> 184
    • 18uA ---> 204
    • 22.2uA ---> 214
  • These are nominal values for the beam current. Gotta get the actual values from epics info.
  • See example in the halog, entry number: 3505501

• Unser calibration
  • run number: 100451
  • target: dummy
  • current values: 0,2,0,3,0,5,0,10,0,25,0,40,0,60,0,80,0,90,0,100,0,2,0,3,0,5,0,10,0 uA
  • Ideally we would have completed two full cycles from 0 to 100 uA, but the beam came back and we decided to go back to production.
  • See example in the halog, entry number: 3499263

Shift Instructions

• Overview
• More detailed instructions
  • Shift Leader
  • Target Operator
  • Third Person

Instructions for important tasks

• Running with the carbon-Hole target
• Running with the optics target
• Running with the dummy target
• Running with the tritium target
• Running with the helium-3 target

JLab Training

• You need to have a JLab account and be an active user.
• All trainings are available HERE.
• You can check the current status of your trainings HERE.

Regular Trainings:

The trainings that we need are:

• SAF110T - Tritium Training
• SAF116kd - Physics Division Work Governance
• SAF103 - ODH Training (Short quiz at the end)
• SAF100 - EH&S Orientation
• SAF801 - Radiation Worker Training
  • If you do it for the first time you need to do a quiz at a JLab computer and a practical test. Afterwards you get your personal dosimeter
  • If you renew your Radiation Worker training you only need to do the quiz.
• SAF110 - After you did all of the above you need the Hall A walkthrough.
• Read and sign the COO/ESAD/RSAD/ERG in the counting room. Electronic copies are HERE.

Tritium Target Operator Training

• Most detailed description of what to do can be found HERE.
• cryotarget training (lets you operate the standard Hall-A/C targets)
  • Contact Greg, JP, and Silviu (see table above) to schedule time to receive a lecture. Lecture slides HERE.
  • Lecture training followed by a practical training with one of them.
  • Take half a shift with a trained Target Operator.
  • Once the steps above are completed, send an email to Meekins, Greg, JP, and Silviu letting them know
• Tritium Target Operator Training
  • Note that this is different from the SAF110T - Tritium Training mentioned above
  • Training consists of going through the slides HERE.
  • Send an email to Meekins letting him know that you completed the training

Documentation

• Run List
• For collimator cut
• Experiment seminar slides
• Run and online analysis slides
• Raster
• HRS DAQ Resources
• Simulation
  • Using MCEEP
  • Using SIMC
  • Using COSY
• Tel Aviv University SRC group
• [back to Hall A wiki]

Target Information

• Tritium Target Tech. Note
• Target Ladder Alignment Survey January 2018
• Information from Jesse

HRS Surveys and Mispointings

• Spectrometer Surveys
  • LHRS Survey, April 17 (during slow and fast2 kinematics)
  • RHRS Survey, April 17 (during slow kinematics)
  • RHRS Survey, April 30 (during fast2 and hydrogen2 kinematics)
  • LHRS Survey, May 2 (during hydrogen kinematics 2)

LVDT retults

Reference Reading

• Proposal for E12-14-011, approved by PAC-42
• Hall-A NIM paper (2004)
• Tech notes on HRS optics calibration
• Hall A Coordinate systems (Ye Zhihong PhD thesis)

Previous (e,e'p) studies

• Hall-A E89-003 16O(e,e'p) experiment
• Hall-A E07-006 4He(e,e'p) experiment

Weekly SRC Meetings (Wednesdays 9:30 ET)

• Files (SRC Meetings)

Bi-weekly SRC Analysis Meetings (Every Other Tuesdays 10:00 ET)

• SRC Analysis Meetings