Page History

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• 8am MCC meeting met incoming LCLS  primary user with ePix (500um silicon for X-rays) who are also battling with radiation damage and showed interests in what we are doing.
•  Did Did a threshold scan (Run 178) on the RTI module and found threshold still narrowed distributed around 3000e but noise got substantially worse at ~500e, 
• Turned off RTI bias from the remote control console, but the LV read back still says 6mV, Caladium ADC Vmon=15mV, Imon=5mV  which are effectively pedestals. Noise up to 1100e when unbiased.
• Reestablished RTI bias for -80V with BK setV=0.080, readback 0.085 and ADC Vmon 0.088-0.093. Threshold scan Run 179: threshold still narrowly groups around 3000e, noise still ~500e, but he right edge bad pixels cleaned up. Bizarre looking noise RMS vs channel map with systematic alternating column pattern and multiple clusters of values within even the same column from 300e – 900e depending on pixel location.      
• 11:00: Used an access to remove Koji's FE65P2 module for shipping.  Now will run YARR parasitically for the remainder of the beam time.  Next move is to do a scan over the RTI module before switching to the cold box.
• Started the beam spot systematic scan over the RTI module by moving the DUT stage. Beam was ~20 particles per crossing. DUT LVL1 peak ta at 4 - moved the original value ~8. Run list see table below.  
• 3 FE65_P2 surveyed by RP and shipped to Koji.

• The almost predictable hang of RCE DUT readout was consistently happening after every 1500-3000 events, that needed HSIO reboot to recover. Later run with old irradiated IBL LUB2 at even much higher particle rate of ~150 were running OK for 10K events. The RTI module data had corruption ? 
• We also saw sudden big burst of noise hits causing temporary peak in LVL1 time distribution which gradually averaged out.
• Call for access to switch to cold box setup. Made new cut out cable slot on cooling box (but under a screw) to allow easy cable exit without running into the MIMOSA plane. Mounted LUB2 as vertically and perpendicular to beam as DUT. Remeasured component vertical position inside box and marked the module center on box. Tried to lower the box into beam but fine Y mover maxed out at the bottom. Lowered the sliding bracket of DUT stage done by ~15mm to keep it in range.
• We dismantled the TLU trigger scope monitoring and put the original cable back to TLU.
• One remaining FE65_P2 is mounted on the back plate of the last EUDET plane down stream. DAQ computer also moved to the back end. LV=5V. Xlinx dongle plugged into the left of the two USB slots of the computer. The YARR readout card connection has a bit of snag as the last mm of the conenction could not go in one one side as it hits the mounting hole shroud so that the HDMI connection is slightly tilted and not all the way in on one side,   
• We notice at some point during the access that the horizontal position of the whole telescope was several cm towards to +x wall according the ceiling alignment laser, but we don't understand how it could have been there.  
• Calibration failed initially when LV was set to 1.5V. It was then realized the for these irradiated old FE-I4A the correct LV is 1.2V. HV is now on remote control.
• 8:25pm restarted beam. Indeed confirmed the whole telescope was way off in X and had to move a long way back to beam. DUT also needed to move up by ~1cm to center to beam.
• HV of -800V was giving LUB2 decent hit efficiency already. The last run with collimator opened to 150 particles/crossing was recorded as Run 648 with config SLAC_1dut_rad_FEI4A. L1V1 timing peak between 5-6. The beam spot shape flip between EUDET and DUT clearly says the DUT x is EUDET -x.            
• 9pm: beam stopped to switch to low E primary. DUT HV off. Our shift ends here.
• Cold box block is <-50C.