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Cooling LSST, the World’s Largest Digital Camera

When it’s ready in 2022, LSST will image almost all of the sky visible from its vantage point on a Chilean mountain, Cerro Pachón, every few nights for a decade to make an astronomical “movie” of unprecedented proportions. To keep the camera cold enough, engineers needed to create a customized...

Ultracold Atoms Could Provide 2D Window to Exotic 1D Physics

In a recent paper in Physical Review Letters, Matthew Foster and Seth Davis, theoretical physicists at Rice University, proposed an experiment to measure fractionalization not in electrons but in atoms so cold they follow the same quantum rules that dictate how electrons behave in quantum materials—a growing class of materials...

LIGO and Virgo Detect Neutron Star Smash-Ups

On April 25, the National Science Foundation's Laser Interferometer Gravitational-Wave Observatory (LIGO) and the European-based Virgo detector registered gravitational waves from what appears likely to be a crash between two neutron stars—the dense remnants of massive stars that previously exploded. One day later, the LIGO-Virgo network spotted another candidate source...

NASA Taps 11 American Companies to Advance Human Lunar Landers

NASA has selected 11 American companies to conduct studies and produce prototypes of human landers for its Artemis lunar exploration program. This effort will help put American astronauts — the first woman and next man — on the Moon’s south pole by 2024 and establish sustainable missions by 2028. Through...

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Regenerators

Regenerators or regenerative heat exchangers are a key component of cryocoolers such as pulse tube cryocoolers (Cold Facts, August 2014). Regenerator performance greatly affects the coefficient of performance of cryocoolers. Improvements in regenerator design and, in particular, regenerator materials have been an important factor in the improvement of the performance...

Pulse Tube Cryocoolers

The development of pulse tube cryocoolers has been a significant topic of research and development over the past 20 or so years. Pulse tube cryocoolers have a number of advantages over other types of cryocoolers and are now available commercially. In order to understand pulse tube cryocoolers, it’s best to...

Thermal Expansion

Thermal expansion refers to the change in size (length or volume) that a material undergoes as its temperature changes. In cryogenic systems this effect can be quite large and must be allowed for in the design. In isotropic materials, which include most engineering materials, the thermal expansion is the same...

Cryogenic Treatment of Materials

F.J. Diekman Controlled Thermal Processing, Inc. info@metal-wear.com Cryogenic Processing (also called cryogenic treatment, and incorrectly “cryogenic tempering”) is a process that uses cryogenic temperatures to modify materials to enhance their performance. Cryogenic Processing involves the slow reduction in temperature of the material to at least -300°F (-185°C) and holding the...

Cryogenics in Space

Peter Kittel University of California-Berkeley pkittel@cal.berkeley.edu Space Cryogenics is the application of cryogenics to space missions. These applications fall into two broad areas, supporting space science missions and supporting the space transportation infrastructure. Science applications: The atmosphere is opaque to much of the electro-magnetic spectrum. In space, the absence of...

Cryosurgery

Review of Cryosurgery Boris Rubinsky, PhD Hebrew University School of Science and Engineering Research Center for Biomedical Engineering 78b Ross Building Givat Ram, Jerusalem 91904 Israel rubinsky@cs.huji.ac.il as published in Annual Review of Biomedical Engineering, August 2000, Vol. 2, pp. 157-187. Abstract: Cryosurgery is a surgical technique that employs freezing...

Liquefied Natural Gas

Liquefied Natural Gas as it relates to the Field of Cryogenics John W. Bonn VJ Systems, LLC johnbonn@vjsystems-lic.com Today the world is looking for a cleaner fuel and Liquefied Natural Gas (LNG) plays a large part in achieving this goal. LNG in a liquid form is at -162°C (-259°F) and...

An Issue of Pressure and Flow Rate in a Supply Tank

Please help solve this problem: A supply tank requires a vaporizer to generate sufficient pressure to pump stored fluid up into a vehicle or tank. The available head is limited as the tank level falls and it is important to minimize the system pressure drop to maintain the desired flow...

Using MLI on VJ Line Joints or Cryo Storage Tanks

When installing Multi Layer Insulation (MLI) blankets on VJ line joints or cryo storage tanks should they be wrapped and tied down tight or loose? These are usually pre-cut to size. Also should they have an access hole at the point of where the molecular sieve is installed to help...