1. Plans for this meeting
Analysis of DNA setup data + improvements of setup
Look into charge readout options of gas detectors (AGET/DREAM chips)
Test new Kaputschinsky + modify it
Put laser in RF mode and repeat fiber tests with laser (since Andrea is on vacation next week)
Prepare talk about light readout of WA105 for protoDUNE DP review (24/25th of April at CERN)

2. Light Monitor System black box with light source outside of cryostat
Air X2
Cryostat
black box with light source outside of cryostat
2 fibers going to cryostat
each splitting into 20 micro fibers (~200 m thick)
either directly on top of cryostat or at bottom of cryostat
22/03/2017
Thorsten Lux

3. larger capacity => more current and longer pulses
Spice simulations:
larger capacity => more current and longer pulses
should provide by a factor 2+ larger signals
larger inductivity => longer oscillation and with smaller amplitude
first only modify C and see if oscillations are observed
100 pF, 100 nH result
470 pF, 200 nH result
470 pF, 100 nH result

4. Kaputschinsky Studies
Standard with 100 pF and 100 nH
Modified with 470 pF and 100 nH
First tests with powermeter => modified Kaputschinsky provides about 7 times more light than standard Kaputschinsky
Afterwards tests with PMT to study time behaviour
2 scenarios studied:
Low DC values (0 > DC > -10 V): PMT close to LED driver
High DC values (up to -20 V): PMT further away + more diffusor material

5. “High” Setup
“Low” setup as “high” setup but PMT closer and less diffusor material
PMT
Kaputschinsky

6. PMT Studies
Modified Kaputschinsky has larger amplitude + longer signal
confirms qualitatively Spice simulations
for low DC values pulse shape for both is Gaussian
for high DC values modified Kaputschinsky shows rectangular shaped signal
define power as product of width and amplitude
overestimates power result for standard Kaputschinsky but good first guess

7. PMT Studies Rectangular shape is not coming from PMT electronics
Signal far from electronics saturation
feature of Kaputschinsky driver
no oscillation observed at this time scale
significant more “power” for modified Kaputschinsky
50 mV
20 mV

8. Related to Light Calibration System
For laser usage at CERN strict safety regulations have to be fulfilled => a lot of administration has to be done
For LEDs the safety responsible answered:
For the LED, no there is no CERN regulation on its use. However, if you will decide to use it, it could be good if you can send us the related documentation.
Thank you! 
CIEMAT considers to use instead of 2 bundle with 20 fibers, 6 bundle with 7 fibers (through 3 feedthrough) or 4 bundle with 10 fibers => Another argument for LED since we could affort only 1 laser but 4 or more LEDs
Material ordered from Thorlabs for further tests (should arrive today)
My latest idea: 4 Kaputschinsky boards controlled by Arduino (or something similar) in a black box + one reference sensor for the 4 LEDs (which could be switched on individually)

9. Other Stuff
WA105: protoDUNE review at CERN went smoothley, especially for us from light readout
WA105: 311 cryostat was forming ice again; warming up again; GTT drilled 60 (!) holes to study/fix the problem; but only on the bottom until now since problems on the top can only be identified when cold; CERN/GTT getting nervous; trying to get it running until 10/2017
WA105: For light monitor system and more will order a power meter + photodiode => 2-3 kEuro
MWPC: wire frame still not mounted; Marc back and looking into data; Joan finished design for preamp and threshold => in production now
Lab: Linde installation still ongoing

10. AGET vs DREAM Chip

11. Plans for next weeks Analysis of DNA setup data
More tests with Kaputschinsky and coupling to fiber