PREX/CREX Thursday, February 13, 2014 10:00am EDT

Link to the Meeting page PREX/CREX Teleconferences
Last meeting: PREX/CREX Thursday, February 6, 2014 10:00am EDT

The teleconference info is as follows:

       Phone #: 1-866-740-1260
       Code: 6931422

Agenda

Updates from Rakitha,

• Plastic Shielding Design Update - 1 elog-2939

Updates from Lorenzo

• Septum pipe Magnetic field elog-2937

Present:

Minutes

• It will be extremely difficult to cover around the scattering chamber with plastic therefore moving part of the shielding into the scattering chamber would be a good idea. At 100 uA, the plastic in the vacuum gets about 12 W and if we don't do anything about this, would the power enough to destroy the plastic by thermal or radiation damage? Main issue with plastic shielding inside the vacuum is heat conductance. We need to know following things,

1. What is the thermal conductance of the plastic
2. What is the radiation hardness
3. What kind of radiation incident on the plastic in the vacuum.

• Proposed tests to get more details about the power deposited in the shielding,

1. Get the spectrum of energy incident on the plastic shielding
2. Get spectrum of what deposited in the plastic shielding (according to the particle type and energy ranges, Main guess is that there are many x-rays incident)
3. Add 1/4 inch copper or lead (high Z) in-front of the plastic to absorb the heat. (We may need 5-10 RL thickness for this) This is assuming that X-rays are the main culprit. Otherwise we may have to use stainless steel or tungsten to block radiation

• What we expect from Robin in Engineering
  • water contact, flow rate, pump capacity and temperature difference are enough to take out 2 kW of power from our collimator.
  • We have to make sure all the possible engineering wise constraints are addressed before making any changes to our collimator design
• Possible time of a PREX Collaboration meeting
  • To discuss outstanding issue
  • To invite people from accelerator and beam-line to update on PREX beam requirements
  • To update the JLab management (Thia and Bob)
  • Possible time would be late March after Qweak collaboration meeting. Proffered to have the meeting before the April PAC meeting

Misc.

• From Last Meeting
  • Beam parasitic studies

TO DO Lists

• Have a optic calibration run plan (disussed in 01/16/2014 meeting)
• It would be nice to have real-time viewer for optics studies in commissioning (disussed in 01/16/2014 meeting)

TO DO Lists link: PREX, CREX