EPS HEP 2015

Recovery Time Measurements of Silicon Photomultipliers Using a Pulsed Laser

Not scheduled

20m

poster Detector R&D and Data Handling

Speaker

Lukas Gruber (Stefan Meyer Institute, Austrian Academy of Sciences)

Description

In recent years, the Silicon Photomultiplier (SiPM) started to replace the vacuum PMT in many of the photosensing demands, ranging from high energy physics to medical imaging. One of the important parameters of photodetectors, especially with regard to the usage in modern particle physics experiments, is the performance in high rate environments. In order to characterize the rate capability and double hit resolution, we performed an experimental study to determine the cell recovery time for various SiPMs and its dependency on the operating voltage. Using a fast pulsed laser we tested three Hamamatsu MPPCs with 25 μm, 50 μm and 100 μm pixels and a sensitive area of 1 mm². These are also the most promising devices for photon detection in the AMADEUS trigger system inside the KLOE detector at LNF. The recovery time is evaluated by measuring the sensor response to two consecutive laser pulses with a varying relative time difference of a few ns up to a few 100 ns. The method represents a direct measurement of the recovery time, which is contrary to the standard method using after-pulses. The results show that the SiPM recovery time constant is in the range of a few ten ns, depending on the pixels size. With small pixel devices two adjacent light pulses separated by only 2-3 ns could be resolved. Experimental data are compared with Monte Carlo simulations to investigate the individual effects influencing the recovery process, such as after-pulsing, cross-talk and dark-noise.

Presentation materials

EPSPoster.pdf