Detectors cryogenic detector

About the present challenges with cryogenics detectors we can mention ... 

In the following sections, we will describe cryogenic sensors and cryogenic detectors, while we will describe the cryogenic experiments in Chapter 16. 

A cryogenic detector is a more complex device able to detect some event as the release of energy by a particle or by radiation. In some cases, a formal separation between sensor and detector is difficult. 

In most cases, a cryogenic detector is developed in view of a definite experiment. 

Because of their high heat capacity, only few of the thermometers described in Chapter 9 can be used as sensors for detectors. Resistance (carbon) sensors were used for the first time in a cryogenic detector by Boyle and Rogers [12] in 1959. The carbon bolometer had a lot of advantages over the existing infrared detectors [13]. It was easy to build, inexpensive and of moderate heat capacity due to the low operating temperature. 

A sensor is only one component of a cryogenic detector. In the simplest case, a detector consists of an absorber (for example absorber of energy) and a sensor (for example a thermometer like a TES). Nevertheless, other physical parameters than energy and temperature may be involved in a cryogenic detector. For example, in a cryogenic gravitational antenna (see Section 16.2) the absorber is the cooled bar, whereas the sensors is SQUID-capacitor system. 

Hereafter, we will describe in detail two examples of cryogenic detectors ... 

Cryogenic detectors (calorimeters) were proposed in the 1980s by Fiorini and Niinikoski for searching rare events like neutrinoless double-beta decay ( 3 3-Ov) [52],... 

The astronomical calorimeters for the detection of the infrared radiation (usually called bolometers) do not conceptually differ from the cryogenic detectors used in nuclear physics as those just described for CUORICINO. 

For a review of early cryogenic detectors see, for instance B. Sadoulet IEEE Trans. Nucl. Sci. NS-35, 47 (1988)... 

Frank, M. Mass Spectrometry With Cryogenic Detectors. Nucl. lustrum. Methods Phys. Res., A 2000, 444, 375-384. 

In cryogenic detectors, a simultaneous measurement of both ionization and thermal energy allows the discrimination of nuclear recoils from electrons produced in radioactive decays or otherwise. This discrimination, however, cannot tell if the nuclear recoil was caused by a WIMP or an ambient neutron. The detector, most often a germanium or silicon crystal, needs to be cooled at liquid helium temperature so that its low heat capacity converts a small deposited energy into a large temperature increase. Only relatively small crystals can be currently used in these cryogenic detectors, with relatively low detection rates. 

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