[Pwg] Collaboration status of Ae+e- proposal (PR12-21-006) and a few updates

[Xiaochao Zheng]

Dear SoLID and Positron supporters:

I am happy to share the report from the SoLID collaboration review on the new Ae+e- proposal. The proposal was reviewed during the SoLID collaboration meeting on June 10-11 and as you can see from the report, that "The SoLID Collaboration endorses this proposal for conditional approval.".  Subsequently, the Hall A Collaboration Committee informed me/us that the proposal was approved for "Hall A Collaboration Status".

I have attached the report here. There are quite a few suggestions regarding the technical side of the experiment (the last point is physics-y as well).  If anyone is interested in leading and/or contributing to the following topics, please contact me:

1) field/mechanical stability study of SoLID magnet;

2) stability in detector efficiency, acceptance, and DAQ;

3) beam current monitor after the target (previously used in "transitional PV" experiments);

4) Analysis or re-analysis of PREX-II with the goal of (a) forming helicity-asymmetries but with h+ and h- data coming a certain time apart; and (b) study long-term stability of asymmetry itself and set bounds on violation of Lorentz invariance, as described for example on page 209 of https://arxiv.org/pdf/2007.14491.pdf: "Lorentz violation in the weak vector-boson sector can be studied in ep scattering via a Fourier analysis of PVDIS asymmetry" → see 1610.08755<https://arxiv.org/pdf/1610.08755.pdf> (HERA analysis) and 1909.10627<https://arxiv.org/pdf/1909.10627.pdf> (projection for FCC+LHeC). Note that while PVDIS is mentioned, PVES in general can be used.

5) Possible analysis of upcoming MOLLER and SoLID PVDIS data with the same goal as 4 above.

Now a tough but necessary request for the positron team:
6) Can we switch between e- and e+ beams more frequently than "once during the experiment"? For example once a week or every other week (as in CERN experiment)?

The timeline for the above tasks will not be "urgent", as none of the topics listed can be done instantaneously and some of them may morph into quite interesting long-term projects.  But it will be useful to make a plan prior to the PAC meeting (week of July 19th).

I'd also like to mention that the PAC presentation for this proposal is scheduled to be at 12:30pm EDT on Tuesday July 20th. I am contacting JLab management to see whether and how collaborators can call in.

Lastly, this single sentence in the review report: "Nothing like this has ever been attempted before", sums up the challenges of the experiment. As I already mentioned in an earlier email: we expect to receive theory and technical reviews -- possibly lot of them -- in early July.  Until then, for those of you in the US, enjoy your July 4th week!

Best regards,

Xiaochao
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/pwg/attachments/20210624/4c2beb18/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: SoLID_rev_Positron_v2.docx
Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
Size: 12639 bytes
Desc: SoLID_rev_Positron_v2.docx
URL: <https://mailman.jlab.org/pipermail/pwg/attachments/20210624/4c2beb18/attachment-0001.docx>