[Rgc] Volunteers needed

[kuhn]

Dear CLAS collaborators planning experiments with a longitudinal polarized target,

after yesterday’s meeting of our run group (RG C), I would like to bring some items to the attention of those of you who couldn’t attend:

1) The Experiment Readiness Review (ERR) for our run group is scheduled for the last week in March, 2019 - that’s only 6 1/2 months from now. Much of the preparation for the ERR will involve the polarized target, but we also need to define the running conditions, run plan, proposed experiments, analysis plans etc. At this point, we hope to use the long shutdown over the summer of 2020 to install the polarized target and run for at least several months in the Fall/Winter 2020-21. So it is not too early to begin in earnest with realistic GEMC simulations of your favorite physics channels. In particular, if you plan to use the FT, you will have to demonstrate that even with rastering the beam the backgrounds (in all detectors, including the FT) won’t be too high to prevent a reliable analysis. Plus ideally we need a strong physics case what is lost without the FT (if there is no strong reason to use it, we will be MUCH better off without it).
We have implemented a semi-realistic version of the polarized target in GEMC - please look at the RGC wiki or ask for pointers.

2) Hall B has set aside some money for beam line elements needed for RG C. This pertains in particular to a possible new Moller shield, if that appears to be required. Again, simulations over the next 2-3 months are absolutely crucial to make this decision, as well as other potential modifications to the beam line.
Also, we URGENTLY need a volunteer to look into all aspects of the raster system:
-> driver, power supplies (are the existing ones strong enough), magnets (strength, cooling, positioning), raster size, raster pattern (pitch vs. beam size) etc. 
This could be a nice job for somebody new joining in. 

As most of you know, we meet every 4 weeks on Thursdays at 9:30 a.m. - the next meeting will be October 4. In the meantime, you can find important information at
https://clasweb.jlab.org/wiki/index.php/Run_Group_C
In particular, take a close look at the Tasklist https://clasweb.jlab.org/wiki/index.php/Tasklist
Finally, if you know anyone interested in polarized physics who hasn’t signed up yet, please encourage them to join the RGC list.

Thanks - Sebastian