Currently at Gran Sasso : Maurizio Goretti, Hunmoo Jeon, Erik Katsavounides,
----------------------- Sophia Kyriazapoulou, Paolo Saggese, Ashutosh
Sanzgiri (shift worker), Stefano Stalio.
Stefano has completed the spare phototube inventory. He reports that there
are a total of 125 spare EMI phototubes of which 43 are labelled good,
66 are bad and 16 have unclear labels. He plans to test these 16 PMTs soon.
There are also 16 spare Hamamatsu PMTs. More details are available in
[SCINTSOFT.PMT.LOG]NEWPMTLOG.LIS on VXMACB. The memo on pmt gain setting is
almost ready and can be found in [MACROUSA.STALIO]PMT.PS on VAXGS. There are
a bunch of bad PMT bases and Stefano will fix these in the near future.
Chris Orth had reported a few weeks ago that some WFD stop masters were
not processing TOHM triggers from adjacent supermodules. Maurizio, Erik
and Ash looked into this problem and noticed that on the SM2 stop master
one of the outputs and the SM+1 input is broken and on the SM4 stop master
the SM+1 input is broken. Maurizio looked briefly into the SM2 stop master;
there are no loose wire-wrap connections, the problems are a little more
subtle. He will debug the stop masters further this Wednesday. The spare
stop master and the one on SM 1 give occasional problems while setting
the stop delays using camac commands, this too needs investigation.
Calibrations were performed last week on SMs 3&4 and this week we performed
LED TDC & laser calibrations on SMs 3&4 and laser calibrations on SMs 5&6.
A scan of last weeks calibration data on SMs 3&4 indicated that the
calibration settings were not being written correctly into the pattern
register (Borer module). The Borer was noticed to be offline and so the
calibrations on SMs 3&4 were repeated this week. There are still some
problems with timing jitter on the SM 1&2 calibrations; also, the laser
calibrations on SM4 revealed a funny behaviour with the ADC for the
attenuated ref PMT (probably caused because the gating signal is too wide) -
Maurizio will look into these problems. He also has some code from Ed Kearns
to monitor WFD channels for misbehavior which he will be running on a regular
basis.
Paolo is building a test bench for TOHM cards. The power supply is ready
and he is awaiting for some sockets & a PCB from Caltech. He is also
working on making backups of the calibration files.
Sophia, Hunmoo and Ash worked on the slow monopole calibrations performed
this Wednesday. Hunmoo has got the program that fires LEDs one tank at a
time working. He also added code to write the tank number and pulse settings
into the calibration pattern register (Borer module). Ash wrote a user
procedure that would decode the data from this module (equip 24) so that
the WFD reads out waveforms for only the tank in which the LED was fired.
The new system files created have been incorporated as the default DAQs by
Francesco Ronga. The calibrations, unfortunately, take up a lot of time
(> 4 hrs) per uVAX with the settings we used (77*2*2 tank-ends per uVAX *
10 LED pulse amplitudes * 10 pulses at each amplitude) - so we were able to
only run them on one end of uVAX 1. Hunmoo is working on trying to get the
calibrations to run faster. The pulse repetition rate is 4 Hz so that the
ERP fake box is triggered for each pulse, but the reset time between different
pulse settings/tanks fired is about 5 sec.
In addition, Sophia performed a variant of the WFD_ADC calibrations on all
uVAXes - here LEDs are fired in multiple tanks at a time and the LED pulse
amplitudes are varied, but the WFDs are not read out. Like the LED TDC
calibrations, these are quite fast (~ 20 min/uVAX). Sophia is analysing the
data to map out the TOHM efficiency.
Hunmoo plans to completely rewrite the code that fires LEDs for monopole
simulation. He has noticed some peculiar behavior with the LED switchboxes -
when the boxes are reset between pulse settings, he sees ~1.2 Volt very sharp
(< 100 ns) transient negative pulses. In addition, the pulses coming out from
ths switchbox are about 10% bigger for horizontal tanks and 10% smaller for
verticals compared to their amplitudes out of the pulser. Further
investigations are in progress.
- Ashutosh Sanzgiri