Detailed setup description and to do
We would like to measure the reflectivity and transmittivity of UV light on samples of detector materials. Here we describe in detail how we would like our setup to work, and what needs to be done for that. [PLEASE ADD ANYTHING YOU CAN THINK OF]
Samples of detector materials
The samples that we would like to study the optical properties of, are materials used in (large scale) liquid xenon dark matter experiments. We would like to investigate how the UV scintillation light generated by events in the liquid xenon interacts with the walls of the detector. We need to be able to place the samples into our experiment without touching the face of the sample, and we need to be able to measure for different angles of incoming light. A sample holder has been designed by Casimir van der Post for this purpose [MAKE A DEDICATED PAGE FOR SAMPLE HOLDER DESIGN].
TO DO
- test placing the sample holder inside the vacuum chamber
- test rotation of the sample holder inside the vacuum chamber
- test placing samples in the sample holder
- test the thermal connection between the samples and the sample holder
- ...
UV light
The bloody wiki threw this away.
Measure
The reflected or transmitted light of the sample will be measured using (an array of) silicon photomultipliers (SiPM). These will be mounted on a sensor holder that can be rotated around the sample holder so we can measure the distribution of light. The intensity of light is expected to be low, so we would like to be able to see single photons. The angle of the SiPM with respect to the sample needs to be registered, as well as the signal from the SiPM. We need to get the signal from the vacuum chamber to the outside without introducing too much noise. Then, outside the vacuum chamber, we need to filter and amplify the SiPM signal and count single photoelectron peaks. Since the SiPM dark count rate is very sensitive to temperature, we also need to measure the temperature inside the vacuum chamber.
TO DO
- design, create and test a sensor holder for the SiPM(s)
- create and test a connection from the SiPM to the bias voltage and to the filter/amplifier outside the vacuum chamber that is vacuum proof and low noise
- design, create and test a counter for single photoelectron peaks
- design, create and test a data acquisition system from the counter output
- test the temperature sensors in the vacuum chamber
- ...