Choose timezone
Your profile timezone:
Powered by Indico
v3.3.5
PXD Operation (Hua Ye, Felix B. Mueller, Bjoern Spruck, Simon Reiter):
Beam incident on June 9:
At the beam incident on June 9 all modules were shut off by the Over Voltage protection. The ramp up went smoothly after that apart for module 1081. For this module a high clear_on current prevents the ramp-up into peak mode. The module is currently excluded. It will be tried to increase the current limit for this mode and power on the module. The other modules are operational although with different current consumptions mostly in the clear_on and clear_off nodes and increased number of dead/inefficient rows.
The mechanism of the damage caused by by the beam accidents is still not completely clear. A test program with with H5 assemblies is being discussed. The idea is to irradiate such a small system including the Switcher with electrons to investigate latch-up and TID effects.
Link drop on module 1042:
The optical links have been remeasured after cleaning of the optical interface. The broken link could not be recovered. Whether the link failure is due to radiation damage of the transmitter or a bad connection at dock-box level will be investigated during summer shut-down.
DHH firmware (Igor Konorov, Stefan Huber):
Occasional loss of data (aka "occupancy drop"):
The root cause of the data loss at high occupancies and under certain combinations of trigger rates is still under investigation together with DHPT experts at Bonn. The current work-around is the deployment of more relaxed veto and trigger hold-off times after injection.
As soon as the gated mode is ready for implementation at the experiment, at least the high occupancy from the injections is suppressed. For the case of bursts during normal operation, a new feature to reset the DHP and re-synchronize DHP and DHH systems is ready and will be tested at the DESY setup.
Gated Mode operation:
After the successful tests of the gated mode at DESY, the test was repeated with two modules at KEK, first without beam. Next step is to do the tests, still with only one or two modules, during beam time to find the right delays and timing for the gates.
PXD 2020:
Sensors (Rainer Richter):
PXD9-20a: The back etching (thinning) of the process wafers is ongoing, still at step 1/13 of phase3, no progress this week.
PXD9-20b: at step 21/22 of phase2
PXD9-21: at step 12/13 of phase1 (runs at low priority as backup)
Module testing queue:
MPP: W04_OB1, W10_OB1, W02_OF1, W09_OF2 (after SWB rework)
- W02_OF1 is still under characterization, no news this week
GOE: W05_OF1
- system is being set-up and tested. After that the characterization can start
HLL: W04_OF1
- system is being set-up and tested. After that the characterization can start
Phase 2 modules:
at Bonn:
W37_OF1: ready for ladder assembly after beam test
W37_IF: currently under test
at HLL:
W46-IB and W37-OB: no news this week
Assembly of new L1 modules:
Due to the Switcher issue, the assembly is on hold. The 250 SwitcherBv2.1 arrived at KIT and will be sent after spot checks to IZM for the bumping process.
Ladder Assembly (Hans-Guenther Moser):
The report for the reviewers has been send out. Ladder assembly will be resumed June 17, after return of the technician from vacation.