[Clas12_first_exp] no rc meeting today and plans for Monday

[Mac Mestayer]

Hello Nick;

I don't think we (DC group) can make use of B=0 
and beam=0 runs.  I'm also not quite ready for
B=0, beam on, alignment runs.  I don't
know the effect of the solenoid - it will reduce
background (good) but may destroy our
beam-vertex constraint (bad).

So, in summary, we are not ready for B=0 data.

- Mac

----- Original Message -----
From: "nick markov" <markov at jlab.org>
To: "clas12 first exp" <clas12_first_exp at jlab.org>
Cc: "Mac Mestayer" <mestayer at jlab.org>, "Yuri Gotra" <gotra at jlab.org>
Sent: Sunday, October 14, 2018 11:49:27 AM
Subject: no rc meeting today and plans for Monday

Dear All,
we have been taking data overnight. The beam was not very stable and we have a few issues with the DAQ. 
The gas supply pressure for DC is still low, but the engineer on call is notified and told he will take care of it.
On top of that, we took a run with the reduced windows for the DC:
https://logbooks.jlab.org/entry/3608918

As of now there is no definitive answer from the MCC on how long the bean studies will take. They have a feeling that it will take less then a full shift. I will let you know as soon as I have an update.
As for plans for tomorrow, I think there are two possibilities:
- if downtime will take 4 hours or more, we will rump magnets down and take zero field Forward Carriage cosmic ray runs;
- if the downtime will be shorter we will not take magnets down and just perform a regular maintenance.

The question I have to the DC and SVT experts is if they want to do a zero field runs, since if the answer is “yes” and we rump magnets down tomorrow, we can take a zero field data overnight until RF studies in the morning.
Best regards, Nick.