[Hallc_running] [Revised Logentry] Status update

sanghwa at jlab.org sanghwa at jlab.org
Sat Feb 17 11:25:03 EST 2018

Logentry Text:
The max current to HallC started decreasing around 4am. The higher current couldn't be delivered due to 3P04 BLM trips (right after the 4th Compton dipole). MCC tried different steering configurations around Compton chicane area, but no luck despite the effort. 

Dave Gaskell went down into Hall for visual inspection of Compton area. Compton detector and support are all in position and secure, and they are well out of way from the beam line: https://logbooks.jlab.org/entry/3533327

The survey result does not show hot spot around the region either except for around downstream quads (3C20, 3C21) from few days ago: https://logbooks.jlab.org/entry/3533318

3H07A and 3H07B spot sizes were reasonably reproduced from Harp scan this morning compared to the last harp scan, and does not show any indication that would have caused 3P04 BLM trips. 3C20 Harp swipes show some horizontal shoulder that was not there on Feb. 14, but the spot size on 3C20 is still considerably small. See https://logbooks.jlab.org/entry/3533259 for details.

As far as Dave's concern, the Compton won't be negatively impacted by masking off the BLM, and after talking to Thia the decision has been made to mask off the BLM.

We have collected ~970 good coincidence events with LH2 at Q^2 = 14.3 so far, and once we recover SHMS Dipole (temperature interlock), we will try to go higher current.

There will be a remote RC meeting at 1:30PM today to give a status update and weekend running, however anyone onsite is welcome to come the conference room in CH.

Link: https://bluejeans.com/543903672
Connecting directly from a room system?
1) Dial: or bjn.vc
2) Enter Meeting ID: 543 903 672
Just want to dial in on your phone?
1) Direct-dial with my iPhone or
+1.408.740.7256 (United States)
+1.888.240.2560 (US Toll Free)
+1.408.317.9253 (Alternate number)
(Global Numbers)
2) Enter Meeting ID: 543 903 672
3) Press #


This is a plain text email for clients that cannot display HTML.  The full logentry can be found online at https://logbooks.jlab.org/entry/3533404
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/hallc_running/attachments/20180217/e520639f/attachment.html>

More information about the Hallc_running mailing list