[Hallc] Pion-LT update and call for shifts

[Garth Huber]

Dear Collaborator:

We are writing to give you a short update on the Pion-LT experiment
(E12-19-006) "Study of the L-T separated cross section at 11 GeV and
measurement of the charged pion form factor to high Q^2", and request your
continued support in helping to fill shifts to run the experiment.  This is an
important experiment that has motivated the 5.50 degree capability of the SHMS,
and has been identified as an "early high impact experiment" by the JLab PAC.

After a slow start, we began taking beam in earnest on Sept 9, and things have
been going fairly well ever since.  A webpage of our data taking progress,
including preliminary physics plots you can look at, is available on the Hall C
wiki at:
https://hallcweb.jlab.org/wiki/index.php/PionLT_2021_Physics_Status

We have nearly completed the data taking at 9.2 GeV, and an important linac
gradient change is scheduled for this weekend.  This will allow us to take data
at 6.0, 9.9 and 8.0 GeV beam energies, which are needed for the L/T-separations
of quite a few of our physics settings.  The draft run plans for these beam
energies are available from the Pion-LT Redmine site at:
https://redmine.jlab.org/projects/hall-c/wiki/2021_Run_Plans_and_Run_Sheets

Due to the 3 week late start up, the experiment run will now continue after the
Christmas break, from Jan 10-Feb 1, 2022.  As the USA is slowly starting to
open up to international travel, we hope this will give an opportunity for some
collaborators further afield who have expressed a desire to contribute to do
so.

The experiment still has a lot of shifts to fill, particularly in Jan 2022.
The shift requirement for co-authorship is 15.  While our preference is for
co-authors to take 10 shifts in this 2021-22 run, followed by another 5 shifts
in the fall 2022 run, we understand this is not always possible.  If you prefer
to take all of your shifts in either 2021-22 or fall 2022, just please let us
know, so we can include this in our experiment planning.

The shift schedule can be found here:
https://misportal.jlab.org/mis/apps/physics/shiftSchedule/index.cfm?experimentRunId=HALLC-PIONLT

Thanks and Regards,
Garth, Tanja and Dave

-- 
Dr. Garth Huber, Dept. of Physics, Univ. of Regina, Regina, SK S4S0A2, Canada.
tel: 1-306-585-4240. fax: 1-306-585-5659.