TRD Weekly Meeting

Monday 8 Jan 2018, 10:30 → 12:15 Europe/Zurich

TRD weekly meeting 08.01.2018

attendees: Ole, Sebastian, Oliver, ALexander, Yvonne, Dennis, Chilo, Tom, Raphaelle, Markus, Klaus, Pascal

start: 10.30 am
end: 11.15 am

minute taker: Ole

====================
status at P2
====================

gas leak (Chilo)
- approx. 800 l Xe lost over christmas break! ~200 l of this due to software bug (gas group tackling this issue), ~600 l due to unknown leak
- alarm in DCS system came (mixer was running for 3 days straight), but was not observed since no shift crew
- Chilo luckily saw this, because the TPC gas system failed and therefore the piquet was notified who notified Chilo who then also checked the TRD gas system
- first the TRD mixer was turned off to see what is going on
- after debugging chilo turned the mixer back on injecting CO2 -> pressure restored, system afterwards behaved correctly
- since last week injecting Xe again
- leak rate now back to normal
- Xe from ~82 to ~81 % because of this incident
- more Xe would need to be injected to restore conditions
  -> Yvonne proposes to go for the old conditions which we had in August at last injection (for trigger operation in pp whilch will start with data taking in 2018)

conclusions: see Chilo's slides
- origin of leak unknown
- maybe a high pressure safety valve? cannot find it right now, since the leak is not visible anymore
- DCS alarm system detected the leak, but since nobody was watching it was unnoticed
- with current bottle (6m^3 Xe) we should have enough Xe for 2018, but we do not have much room for more leaks
-> DCS alarm panel should be watched more closely from TRD experts, SRC, operators etc. 
-> Oliver: install E-mail alarm (alarm is currently still be visible in WinCC), in order for these very important alarms to not be left unnoticed

DCS update (Oliver)
- TRD PAR in development to adjust HV during the run in case of ambient pressure changes above given threshold
- ambient pressure alarm will be replaced by automatic adjustment
- HV adjustment settings should be put in the OCDB (voltages are currently stored, but without a flag for the adjustment -> Oliver will check how this can be integrated in the OCDB)
- needs to be tested

repair workshop in Muenster (Tom)
- everyone who is still around mid 2019 for the repair and/or has experience with the SMs is welcome to join

====================
offline
====================

TRD software issue (Raphaelle)
- MC productions anchored to LHC17i are on hold because of us!
- different number of time bins for few chambers are producing AliFatals crashing the productions
- Raphaelle will ask Jochen for help and put Tom in cc!
- either mask chamber in data AND MC and check that the production do not crash anymore, or change configuration of the misconfigured chamber(s) to the majority and ignore wrongly configured chamber
- to be followed up offline!
-> how to detect this in the future?

10:30 → 10:50 status gas system Christmas

Speaker: Chilo Garabatos Cuadrado (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))

leak_Xmas_2017.pdf

10:50 → 11:00 AOB