sPHENIX cold QCD topical group

[Alexander Bazilevsky <shura AT bnl.gov>]

Thanks, Itaru, for compiling the info!

Besides the scaler (GL1P) data, we also need event data: as a maximal 
set - for all triggers included in GL1P, and as a minimal set - for MBD 
coincidence trigger and CLOCK (e.g. to study vertex distribution at each 
beam position to understand the hour glass effect).

Since during the vernier scan run our rates vary by a few orders of 
magnitude, we can not set up reasonable trigger scaledowns which would 
provide both good life time and good DAQ rate at each step. Therefore we 
used to release the scaledowns for triggers we collect to saturate the 
DAQ rate regardless the life time (with the goal to collect as many as 
possible of triggers we want).

So, I suggest the following scale downs:

CLOCK: 10k
MBD N&S >= 1: 0
ZDC Coincidence: 0

Not sure how useful could be the one-side trigger data, but if we can 
afford enabling them, I'd suggest the scaledowns:
ZDC-North and ZDC-South: 10
MBD S >= 1 and MBD N >= 1: 50

In this configuration, the major bandwidth will be occupied by CLOCK and 
MBD N&S, and only a few % for all other triggers (not necessary, but may 
be useful).

Regards,
Sasha.



On 7/9/24 5:01 AM, Itaru Nakagawa wrote:
> Dear Sasha and Ralf,
>
>  Here is the draft instruction for the vernier scan. Unfortunately I 
> cannot find any instruction of the data taking in PHENIX, but here is 
> what I think is the procedure. Please have a look and send me feedback.
>
> Best regards,
>
> -itaru

--
Alexander Bazilevsky
Brookhaven National Laboratory, Bldg. 510D, 2-232
Upton, NY 11973 Tel: 631-344-3712
Email: shura AT bnl.gov
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