Next generation multi-ton scale noble liquid experiments have the unique opportunity to discover dark matter particles at the TeV scale, reaching the paramount sensitivity of 10^-48 cm^2 in the WIMP nucleon scattering cross section. A prerequisite will be the reduction of radiogenic background sources to negligible levels, only possible if ultrapure high efficiency photosensors are available for the scintillation light readout. Major requirements for the next generation experiments' photosensors are: high quantum efficiency, high gain, high single photon resolution, wide linear dynamic range, good time resolution, relatively large sensitive area, low radioactivity, low power consumption and low price. Ultralow radioactivity cryogenic photomultipliers have a metal body, a quartz window and a specially manufactured low temperature photocathode. Radioactivity of the metal and ceramic parts of the electron multiplication system is a key concern as a factor 100 improvement in radiopurity would be necessary. Moreover, large limitations of the PMTs performances are observed at low temperature, with emphasized fatigue, hysteresis and breakdown effects, especially at liquid argon temperature. An attractive alternative is represented by the silicon photomultiplier arrays (SiPM arrays), with much lower intrinsic radioactive background and smaller mass in addition to unrivalled performances in single photon detection, enhanced in the cryogenic environment. An overview of the planned development undergoing at INFN Napoli and LNGS in collaboration with FBK will be presented as well as preliminary results of the SiPM behaviour as a function of the temperature.
SiPM development for LAr DM experiments
Piemonte, Claudio;Gola, Alberto Giacomo
2014-01-01
Abstract
Next generation multi-ton scale noble liquid experiments have the unique opportunity to discover dark matter particles at the TeV scale, reaching the paramount sensitivity of 10^-48 cm^2 in the WIMP nucleon scattering cross section. A prerequisite will be the reduction of radiogenic background sources to negligible levels, only possible if ultrapure high efficiency photosensors are available for the scintillation light readout. Major requirements for the next generation experiments' photosensors are: high quantum efficiency, high gain, high single photon resolution, wide linear dynamic range, good time resolution, relatively large sensitive area, low radioactivity, low power consumption and low price. Ultralow radioactivity cryogenic photomultipliers have a metal body, a quartz window and a specially manufactured low temperature photocathode. Radioactivity of the metal and ceramic parts of the electron multiplication system is a key concern as a factor 100 improvement in radiopurity would be necessary. Moreover, large limitations of the PMTs performances are observed at low temperature, with emphasized fatigue, hysteresis and breakdown effects, especially at liquid argon temperature. An attractive alternative is represented by the silicon photomultiplier arrays (SiPM arrays), with much lower intrinsic radioactive background and smaller mass in addition to unrivalled performances in single photon detection, enhanced in the cryogenic environment. An overview of the planned development undergoing at INFN Napoli and LNGS in collaboration with FBK will be presented as well as preliminary results of the SiPM behaviour as a function of the temperature.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
