E-rhic-ir-l mailing list

[Bill Christie <christie AT bnl.gov>]

Dear All,
    Below please find the minutes from our eRHIC IR Design meeting that 
was held on Friday, 3/2/2018. Please note that our next meeting will be 
on Friday March 16th, and as discussed, we'll start at 3 pm.
    Greetings,
        Bill

    Minutes from the eRHIC IR Design meeting held on 3/2/18
 
-------------------------------------------------------------------------------
* We started with a review, and agreement of/on the Agenda:
    - "Final pCDR" Presentation of Tables
    - Update on Simulations
    - Update from Charles on the Vacuum design
    - Update from Alexei on Impedance calculations
    - AOB

* Discussion of "Final pCDR" Tables: Elke
  - Elke indicates that it has been a productive week, working with 
Guillaume, Steve, and Alexei.
  - Has everything on the Electron IR table
  - Getting final info. on the hadron IR table
  -> Looks good
  - What's missing is the acceptance (i.e. apertures). Will get this 
info. from Holger and Brett
  - Hoping to input vacuum chamber files
  - Proposes that we stick with the present "Madex" file format.
  - Brett brings up the question of the magnet offsets and rotations.
       - Elke has been asking Guillaume and Steve for this info.
           - Guillaume indicates that for the hadron line he has 
included the magnet rotations. The Magnet positions in the files should 
be Ok.
       - In Madex file there is both a focusing and a bending strength
       - Elke asks whether there are rotated magnets in the Electron line
           - Answer is yes, on the outgoing side.
  - After discussion, Elke offers to draft a document detailing all of 
the magnet info.
     - Idea is to iterate on this document between now and the next 
meeting.

* Simulation Update: Elke
  - Preparing these magnet tables so that process can get going.
  - Working with Charles to simplify the vacuum geometry files so that 
they can be imported to simulations.
  - Question about how far out along the beam lines the simulations go?
      - Answer is out to the crab cavities. Perhaps can extend out to 
the first RHIC magnet.

* Vacuum Update: Charles
  - Met with Mike Mapes. Went through the cost estimate. Added in some 
new info.
    - Elke will a number for the Roman pot scattering chamber
      - Likely this cost is in the cost estimate twice. Charles will 
update and fix this using Elke's info.
  - Starting the text write up.

* Impedance Update: Alexei. File "IR pipe impedance mode w subtraction.pdf"
   - Shows a few slides
   - Shows the geometry for the vacuum chamber, concentrating on the 
region where the internal electrostatic shield for the electron beam 
attaches in the region about the center of the detector region.
      - This region is a problem
      - on the outgoing hadron side he has an idea how to arrive at an 
acceptable solution.
  - Discussion about what the needed acceptance is for the scattered 
hadron, and effect of the electrostatic shield opening and attachment point.
  - Alexei went briefly through the text he is writing up.

* Introduction into how to deal with the ion beams: Elke
  - In the e-p running the asymmetric divergence of the beam has an 
impact on the luminosity and the achieved acceptance.
  - Vadim indicates that he will start looking into this for the ion beams.

* Next meeting date will be Friday March 16th.
    - The start time will be shifted to 3 pm.
    - Draft Agenda:
       - pCDR Final Tables
       - Simulation update
       - Vacuum Update
       - Impedance update
       - Dealing with ion beams update
            End of meeting

Attachment: IR pipe impedance mode w subtraction.pdf
Description: Adobe PDF document