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, 6/22/2018. Please note that our next meeting will be 
on Friday July 6th, at 3 pm.
    I note that there may be a number of people that are looking to 
take days off next week due to the July 4th Holiday in the middle of the 
week. I know we discussed this, but I wouldn't be adverse to delaying 
our next meeting until the following week (e.g. Wednesday July 11th) if 
most of the group wishes. Friday July 13th is the RHIC annual Retreat, 
which is why if we move it I suggest something like the 11th.
    Greetings,
        Bill

  Minutes from the eRHIC IR Design meeting held on 6/22/18
 
---------------------------------------------------------------------------------
* We started with a brief discussion of the agenda for the meeting.
    - We note hat Alexei s not in town (World Cup) so we defer the 
discussion on the impedance simulations.

* Doug Holmes on effort to see how/if things fit in the existing RHIC 
Halls and tunnels:
    - Still gathering input
    - Will get additional info. from Brett and Holger
    - Try to have a "First look" figure for the next meeting in two weeks
    - Discussion that the "MADX (?)" file doesn't have the transverse 
magnet dimensions (i.e. shows cold mass dimensions, but not cryostats).
    - Elke will pass info. to Doug on the magnet locations.
    - Bill brings up the need to try and get to the point that the 
necessary movement requirements for the sPHENIX detector platform can be 
detailed, which would allow for the possible positioning of the sPHENIX 
assembly for eRHIC operation.

* Presentation by Alexander: File ayk-2018-06-22-bnl-ir-meeting.pptx
    - Slide #2, Overall status
        - p-side discription is in pretty good shape
        - e-side description needs more work(?).
    - Slide #3: Hadron going side
        - Shows a momentum resolution plot
    - Slide #4: Hadron going side (2)
        - Spectator protons acceptance and angles
        - no issues for recoil protons
    - Slide #5: Electron going side
        - Discusses how flanges/vacuum system components are input to 
the simulations.
    - Slide #6: Low Q**2 Tracker
        - Shows location, and plot of low Q**2 distribution.
            - Plot key: Black = everything, green = 
aperture/acceptance, Blue = acceptance beyond 10 sigma

* The agenda had a topic to view/discuss a new Figure from Bob
       - Nothing sent for this meeting.

* Brett walked us through his draft slides for the LHeC meeting the 
following week in Paris.

* Guillaume asks about the level of detail that Doug has in his model 
for the Crab Cavities
        - Answer is that most/all known details are in the model.
    - This led to a discussion about a recent change to the electron 
ring geometry. A figure on the chalk board showed this, apparently very 
recent, change.
    - This also led to a discussion about what coordinate system 
everyone should use for these discussion, geometry files, etc.
        - Guillaume indicated he'd send out a proposal for a coordinate 
system for us to work in.
        - Steve T. indicated he'd look for a link to the official 
"RHIC" survey coordinate system.
            - Steve did send the link. It is:
https://public.bnl.gov/docs/cad/Documents/Accelerator%20Physics%20Coordinate%20Conventions.pdf

* Next Meeting, and Draft Agenda:
    - Next meeting Friday July 6th, at 3 pm
    - Draft Agenda:
        - Alexander, an update on the simulations
        - Doug Holmes on draft figure of how things fit in the tunnel 
(if draft available by the meeting)
        - Guillaume on a Coordinate system proposal.
                        End of meeting.