telnet 128.141.143.237 1527

* RUN after gas stop* *

From run 739346 new config: config_FE1_sdhcall1_5 (no root writing)

RUN: 739342: switched off HV in 2am.

— DAQ user 2018/03/02 06:55

I stop run 739333. The noise is reasonable

• 3 / 2.5 ms on TDC8
• 5 / 2.5 ms on TDC5

⇒ The noise seen @ higher HV is coming from the chamber

I restart with 6700 V

— DAQ user 2018/03/03 15:45

There was acrash of the event builder , most probably due to rootwriter Monday I will supress this root file writing

In the mean time in case of problem:

daqcontrol --jc-kill

daqcontrol --jc-start;daqcontrol --daq-create;daqcontrol --daq-disc;daqcontrol --daq-serv;daqcontrol --daq-init;daqcontrol --daq-conf

/home/acqilc/prepare_cosmic

daqcontrol --daq-start
daqcontrol --trig-resume

HV applied = 6800 V , Scintillator on TDC 8

P from 966 to 969 (462→465) T ~ 22,22.5 C

— DAQ user 2018/03/22 05:44

I keep the same setting but rise the HV to 7 kV and make few points

— DAQ user 2018/03/26 17:26 I patched the code to write only 0.1 % of noise event and only trigger events

— DAQ user 2018/03/28 14:58

Run were stopped to investigate current increased and noise. Moreover on 2 strips (79 & 81)of TDC8 I now see a jump of 2.5 ns to be understood.

The jump is due to the abscence of global reset of all TDC counter so from one reset to the other the TDC channel may be displaced by one clock. Following Imad idea I align all the strips to one and repeat runs in same conditions (6900 V) to check the stability

Iuri prepared large scintillators that we put in 1/4 position. It s between the High Radius and central one to guarantee the full acceptance. All 4 Febs are on. We start on 16/04.

We put in 3/4 position. It s between the Low Radius one and central one to guarantee the full acceptance. All 4 Febs are on. We start on 17/04. In fat we realized later that there was a non efficient region at the end of th scintillator. So we repeated some measurement, see below.

Now runs collected with radom trigger of few kHz for the noise:

We realized looking on GAP footprint (black line) that there might be some acceptance problems for edge of the scintillator. So we moved the scintillators backward and ~5 cm closer to the center to be sure that we have full acceptance. Restart few runs with cosmic trigger.

Change threshold to 510 to see how noise goes down.

We use CS 137 radioactive point like source with an activity of few MBq

Th chamber was refurbshed wit bars to make it eligible for the trolley. First we do a noise scan at THR = 506.

we use now KODEL scintillators in synch. positioned above the setup. Ths run is not good for efficiency only for T0 resolution. The rate is ~0.2 Hz. Position 1/4.

The run above had a fundamental hassle that 2 KODEL scintillators 30 cm above the chamber covered with muons a large part of the chamber that is bad for dT0 resolution. So after some attempts we added a large scintillator below the detector to reduce the angle of detected muons. The rate went down to 1 muon / minute.