Star-fst-l mailing list

["Visser, Gerard" <gvisser AT indiana.edu>]

I think we are running with the IST setting for 4 timebins, adjusted up by 2 (RS/4) tics because we now have 9 timebins and would like it centered in same place.

It's supposed to be right, unless STAR trigger latency changed since IST operations (which I am not certain it did not).

If there is not one clean peak I agree that is odd. Sorry but I am about to head to airport and will be offline mostly all day. No time right now to look at the plots, but tomorrow I will.

      Gerard

---

From: Star-fst-l <star-fst-l-bounces AT lists.bnl.gov> on behalf of Tonko Ljubicic <tonko AT bnl.gov>
Sent: Saturday, November 20, 2021 12:08 PM
To: Star-fst L <star-fst-l AT lists.bnl.gov>
Subject: [Star-fst-l] FST timing relative to trigger

 

Hello,

what I think we should do is make _sure_ we are
seeing the correct trigger crossing. Looking at the
timebin plots (where the x-axis is the timebin, 0 to 9)
I'm not sure we do. We see 2 peaks which I don't
understand at all.

First, we should make the ZS data used in the plot
more stringent, with a higher N-sigma cut so that
we think it is an actual particle and not just noise.
For this exercise I would even exaggerate a bit,
e.g. 6 sigma.

Secondly, we should do a quick scan of the global
APV latency-from-trigger (there is such a register,
can't remember the actual name) by moving it in
e.g. 100ns steps or so. Where does the current
setting come from, BTW? Gerard?

I picked up a Cosmics run with IST from 2015
and you can find the same plot attached. Note the
peak.

           -- Tonko