SiPM Array Characterization for Dual Phase XeNeu Time Projection Chamber

Dark matter is an invisible, non-baryonic form of matter that interacts primarily through gravity. Although it interacts very weakly with normal matter, it makes up a significant portion of the total mass in galaxies and plays a crucial role in their structure and evolution. One leading hypothesis is that dark matter consists of weakly interacting massive particles (WIMPs). To search for WIMPs, researchers use liquid xenon time projection chambers (TPCs) to detect the rare and subtle interactions these particles may have with xenon nuclei.

The XeNeu experiment advances this search by studying nuclear recoils in a liquid/gas xenon TPC, which are produced by neutrons. Silicon photomultiplier tubes (SiPMs), like traditional photomultiplier tubes (PMTs), convert high-energy photons into detectable electrical signals. Replacing XeNeu’s PMTs with a 3×3 SiPM array will enhance event reconstruction within the TPC. Before implementation, each SiPM must be tested to ensure that every channel functions correctly. By examining how each microcell responds to both dark pulses (self-generated signals) and external light sources, researchers can verify the performance uniformity across channels. Once validated, the SiPM board will be integrated into the XeNeu TPC to improve the detection and understanding of weakly interacting nuclear recoils.