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RAP (Rivelazione Acustica di Particelle) is a small cylindrical aluminum bar (l = 500 mm, d = 181.7 mm) placed at the DAΦNE Beam Test Facility, where it is hit by a 510 MeV electron beam, coming from the DAΦNE Linac. Aim of the experiment is to measure the mechanical vibrations of the bar caused by the interaction with the beam. On June, 2004 RAP successfully collected data for the first time at cryogenic temperature. Several runs at different temperatures (4.5, 70 and 273 K) have been performed and a number of shots in normal-conducting state of the bar were detected. The preliminary results are in good agreement with the Thermo-Acoustic Model. In the next months the mounting of a dilution refrigerator and the data taking of the bar in the superconducting state (T = 100 mK) have been planned.

A global shortage of helium gas can seriously jeopardise the scientific programmes of neutron scattering laboratories due to the use of cryogenic sample environment in the majority of the neutron scattering experiments. Recently developed cryogen-free technology allows a significant reduction or even a complete elimination of liquid helium consumption. Here we review the impact of the cryogen-free revolution on cryogenic equipment used at large neutron facilities, such as cryostats, dilution refrigerators, superconducting magnets and other cryogenic systems. Particular attention is given to the newly developed superconducting magnets for neutron diffraction and spectroscopy experiments. Use of the cryogen-free approach, as well as cutting-edge superconducting magnet technology and advanced neutron optics allows researcher to achieve extraordinary performance in their experiments, opening up new opportunities in neutron scattering research.

LCGT is the large scale cryogenic gravitational wave telescope project in Japan in order to firstly detect gravitational waves. After the detection, the detector will be served as an astronomical tool to observe the Universe in collaborative observation with Advanced LIGO, GEO HF, Advanced Virgo and AIGO detectors. LCGT will contribute both the enterprise of detecting the gravitational wave events and the worldwide network for gravitational wave astronomy. This paper summarizes the status of LCGT.

Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes — the liquefier and refrigerator modes — will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80 K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

Cryogenics is the study of the production of very low temperature (below −150°C, −238°F or 123K) and the behavior of materials at those temperatures. Similarly, cryogenic grinding is a term supported by the act of grinding a thing at very low temperature. This technique is generally used to grind the material, which contains heat labile constituents viz- volatile oils in seed spices. Due to high fat content in spices, heat is generated, while energy is used to fracture a particle into a smaller size in conventional grinding process. During the normal grinding process, this generated heat causes temperature rise of grinder upto 95⁰C. The increased temperature is responsible for a loss of volatile content in the tune of about 30% and also produces dark colour powder.

Generally, continuous operation is not possible in normal grinding process due to melting of fat and sticking of powder on the grinding surface. The loss of volatile content can be significantly reduced by cryogenic grinding technique using liquid nitrogen or liquid carbon dioxide that provides the refrigeration needed to pre-cool the spices and maintain the desired low temperature by absorbing the heat generated during the grinding operation. The extremely low temperature during grinder condenses the volatile matter and retains their presence in spices. The application of cryogenic technology for grinding of spices has been scientifically proved to be a suitable technique with negligible loss of volatile content and improved colour of oil and grinding operation of seeds.

KAGRA is a new gravitational wave detector which aims to begin joint observation with Advanced LIGO and Advanced Virgo from late 2019. Here, we present KAGRA’s possible upgrade plans to improve the sensitivity in the decade ahead. Unlike other state-of-the-art detectors, KAGRA requires different investigations for the upgrade since it is the only detector which employs cryogenic cooling of the test mass mirrors. In this paper, investigations on the upgrade plans which can be realized by changing the input laser power, increasing the mirror mass, and injecting frequency dependent squeezed vacuum are presented. We show how each upgrade affects to the detector frequency bands and also discuss impacts on gravitational-wave science. We then propose an effective progression of upgrades based on technical feasibility and scientific scenarios.

We demonstrated a cryogenic mirror suspension for a gravitational detector, KAGRA, and evaluated several performances such as cooling time and damping control. Cooling mirrors is promising technique for reducing the mirror thermal noise that fundamentally limits sensitivity of current ground-base gravitational-wave detectors around 100 Hz region. Cryogenic technology for mirror suspensions is therefore essential for further improvement of detector sensitivity beyond the 2nd generation detectors such as aLIGO, aVIRGO, and KAGRA. In this paper, current status of KAGRA cryopayloads is discussed.

The wiring of CUORE experiment consists of about 2600 NbTi leads. One end of each lead is at 300 K whereas the other end is at 10 mK. Due to the design of CUORE cryostat, a thermal grounding at the first refrigerating stage (40 K) is not feasible. Moreover, for such a large numbers of wires, sinking heat at 4 K by glues is hazardous. Hence, we propose an unconventional thermal grounding of the wires carried out completely by radiative exchange. The thermal loads onto the sinks at 4 K, 0.7 K, 10 mK are reported.

LCGT shall be planned to be the large scale cryogenic gravitational wave telescope in order to firstly detect gravitational waves. After the detection, the detector will be served as an astronomical tool to observe the Universe. In collaborative observation by Advanced LIGO, GEO HF and Advanced Virgo projects, LCGT is desired with AIGO to contribute both the enterprise of detecting the gravitational wave events and the worldwide network for gravitational wave astronomy. This paper summarizes the status of LCGT.

Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes — the liquefier and refrigerator modes — will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) is a direct Dark Matter detection experiment located in the Gran Sasso underground laboratory. In 2011, the CRESST–II Dark Matter search completed 730 kgd of data taking operating scintillating CaWO4 crystals at mK temperatures. The simultaneous detection of the deposited energy by the phonon signal and the scintillation light allows the discrimination of the interacting particles on an event-by-event basis. In the acceptance region of the detectors, 67 events where observed in total. A maximum-likelihood analysis shows that an additional signal on top of the known backgrounds of α–, β–, γ–radiation and neutrons is required to explain the observed distribution both in energy and light–yield. The excess signal however is compatible with the signal expected from a WIMP (Weakly Interacting Massive Particle) with a mass in the range of 10–30 GeV/c².