VUVProjectsPlanning

Update January 2023

Task (measurements)	DRI	Main dependencies	Status	Finish by
Measure fluorescence efficiency of PTFE	Emily
Measure reflectance of cryostat components	Marjolein
Measure optical properties of Arapuca components	Vikas
Measure the spectrum of the D2 lamp	Jasmijn		Done	Dec 1
Gain characterization of SiPMs
Measure excitation beam intensity as function of SiPM position and slit width
Measure time stability of D2 lamp intensity
DN vs temperature characterization of SiPMs	Lucia		Done	Feb 4 or 7
Determine effect of exposure to radiation on fluorescence of plastics

Link to measurement procedure document: File:Measurement procedure.pdf

Task	DRI	Dependencies	Date
Source samples (later: clean, machine and store)	Emily
Design a sample storage system	Emily		Jan
Dark count measurements	Vikas/Lucia		Jan
PT100 calibration			Jan
Check the gains from the electronics in use
Study the time-dependence of the beam intensity		Access to the setup
Check the beam geometry on the samples in the holder		Access to the setup/photosensitive paper arrived
Nuisance light check		Access to the setup
Determine a method to align the sample holder after installation

Task (move and January DC project)	DRI	dependencies	Status	Deadline
Pack all tools and parts that belong to the VUV setup in boxes	Emily and Marjolein	Boxes arrived	Done	Dec 13
Put the DAQ for the SiPM and the temperature readout equipment together so the complete system necessary for DC rate measurement can be moved independently. Room is TBD	Emily and Marjolein		Done	Dec 13
Check if the VUV setup table fits through the corridor. If not, we have to disassemble so let's hope it fits.	Marjolein		Done	Dec 12
Identify dark box to be used for DC measurement.	Tina			Dec 16
Test Peltier element and plan how to integrate it in the dark box and with the SiPM and PT100		Power supply for Peltier element		Dec 16
Set up PT100 read-out and SiPM read-out through dark box	Vikas (Lucia, Tina)		Done	Jan 12
Develop procedure to keep SiPM at specific temperature for ~15 minutes at a time (what voltage/current is needed?) and determine if a large enough temperature range is accessible with this element (if not, ask Tina to order the next size up)	Vikas (Lucia)	Temperature range might need to be increased for future dark box measurements. Unlikely to go below 0° for full setup atm.	Done	Jan 13
Script to plot DC rates as function of temperature	Marjolein (Lucia)		Done	Jan 20
Script to fit the "DC rate versus temperature" curve	Lucia		Done	Jan 27

Task (hardware)	DRI	Main dependencies	Status	Finish by
Read out pressure sensor and debug code	Marjolein	Vikas	Done	Sept 23
Check if lamp noise is still there/what it looks like now	Emily		Done	Sept 23
Cooling system for sample/SiPM planning and component ordering (design, simulations, quotes for components)	Emily		Done	Sept 27
Get SiPM signal out of vacuum (1 channel for now, 9 channels eventually)	Emily		Done	Oct 1
Leak check vacuum system and fix leaks - clean vacuum chamber - pump down and check pressure + pump-down time - tighten bolts on monochromator and feedthroughs - pump down and check pressure + pump-down time	Marjolein (Jasmijn)	Pressure read-out working	Done	Oct 1
SiPM signal output - Adjust readout frequency cutoffs (Hans' one-channel board) - Test SiPM signal (noise) when pump and lamp are on, fix if necessary - Connect and test the Zurich board - signal-to-noise - Figure out what changes if any are needed to bias and read the fluorescence measurement SiPMs - Design and get a SiPM connector plug for inside the vacuum	Emily	Vacuum/light leak eliminated	Done	Oct 7 (Oct 20 for the new board)
Design SiPM array holder for fluorescence	Marjolein/Emily	Preliminary analysis of sensitivity needs finished	Started	Nov
Design SiPM array holder for reflectance/transmission	Marjolein	Analysis of physics goals finished		Nov
Get SiPM signal to disk such that single-pulse rates can be measured (programmable CAEN digitizer for now, V1720 with XAMS-like read-out later)	Marjolein (Jasmijn)			Nov
Get sample holder (fluorescence design) built	Emily		Done	Nov
Calibrations start	Emily Marjolein	Minimum working setup		Dec
Install cooling system (LN2 plate, thermal shorts, LN2 fill system, super insulation)	Emily	Delivery of components/LN2 approval for lab		Dec/Jan
Set up slow-control read-out and data storage, monochromator motor control	Vikas -> ?			Jan

Task (review and calculations)	DRI	Status	Finish by
Estimate sensitivity needs for observation of the PTFE fluorescence measurement in the setup (preliminary, rough calculation)	Emily (Jasmijn)	Done	Oct 28
Review past reflectivity setup design/sample holder (that had XENON in mind) in light of DUNE needs	Marjolein	Done	Oct 30

Update August 2022

PhDs:

Vikas: At CERN until end of the year. Will work a little bit with CT technician to get code and slow control in good shape.

Emily: Focus on getting the SiPM signals to the digitisers. Work with Hans from ET department.

Marjolein: Focus on getting the data from the digitisers into a good format. Work with Maricke/Joran to copy XAMS read-out software.

Undergraduates:

Ilze (start Sept 12, HBO internship): Get vacuum chamber working correctly, design improved SiPM holder. Measure beam intensity as function of distance using SiPM

Jasmijn (start Sept, AUC capstone project): Measure lamp spectrum. Based on expected PTFE fluorescence efficiency, calculate amount of light expected on SiPM, and whether that is measurable over the DC rate

Not free: Monday 11-14, Tuesday 11-13, Wednesday 9-12, Thursday 16-18, Friday 16-18

Lucia (January 2023): Measure the SiPM DC rate as a function of temperature. About 6 hours per day.

Projects for distibution

1. SiPM array and holder --> reflectivity design (modelling/ mechanical viability/ feedthrough positioning)
2. SiPM array and holder --> fluorescence design (modelling/ mechanical viability/ movement inside chamber/ solid angle coverage)
3. Cooling system for sample holder/SiPMs (CAD/COMSOL/ LN2 bath)
4. Put together a plan for data taking

Vacations

Tina:

• Vacation: December 20th to January 8th
• Collaboration meeting (DUNE): January 24-27
• Collaboration meeting (XENON): January 31 - Feb 4

Marjolein:

• Vacation: December 16-January 16th
• Collaboration meeting: January 23-27 (maybe a few days more)

Emily:

• Vacation: December 23rd to January 9th
• Collaboration meeting: January 30th - February 3rd

Vikas: