Cryogenics detectors
Responsible of the WP: Julien Billard
j.billard@ipnl.in2p3.fr
Many applications in astroparticle physics and cosmology require detectors with an extremely low background and the possibility to control and measure feeble energy deposits. In this context, cryogenics detectors have the advantage to measure the power or the energy deposited in the absorber by means of the induced thermal effects. For these reasons they operate at very low temperatures, close to the absolute zero. Traditionally sensors are called cryogenic if their temperature is below the liquid helium (4K), some of them are working at temperatures as low as 10mK.
There are two main classes of cryogenic detectors:
- Individual, massive bolometers typically from a few g to the kg scale. Main application is the detection of rare processes such as the search of new physics beyond the standard Model, including the direct Dark Matter search, the neutrinoless double beta decay (0𝜈ββ) and the Coherent Neutrino Nucleus Scattering (CE𝜈NS). Simultaneous measurements of heat and ionization or light can help to mitigate the expected backgrounds. Ongoing R&Ds aim at enhancing the sensitivity and lowering background level.
- Bolometers arrays, produced using collective manufacturing processes, which can reach several thousand small pixels, therefore providing improved energy, spatial and time resolution. Principal sensor technologies are the Kinetic Inductance Detectors (KIDs) and superconducting Transition Edge Sensors (TES) arrays. The applications of these detectors are mainly in cosmology and in the mm/sub-mm and infrared fields but can cover, in principle, a much wider band, including X or gamma rays.
The cryogenic detectors development is currently very active and the French community has a world-leading expertise in the field.