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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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Two-Phase Flows

Two-phase flows are those flows in which there is a mixture of two physical states (solid, liquid or vapor). In cryogenic applications, such flows are almost always a mixture of a cryogenic liquid along with its corresponding vapor. A mixture of liquid helium and helium vapor would be a typical...

Supercritical Fluids

A supercritical fluid is defined as a substance whose temperature and pressure exceed those of its critical point. Every pure substance has a critical point that is defined in thermodynamic space by a critical temperature and a corresponding critical pressure. For example, the critical point for helium has a critical...

Brayton Cycle

The Brayton cycle is one of the many thermodynamic cycles used to generate cooling at cryogenic temperatures. Strictly speaking, when referring to cooling we should call this the reverse Brayton cycle as the original Brayton cycle describes the process of power generation or propulsion via a gas turbine. In many...

Magnets

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. Particle physics uses accelerators to recreate the conditions of the early universe in an attempt to piece together the complex puzzle of how we got to where we are today. These huge machines are used...

Energy Storage

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. With power lines increasingly congested and prone to instability, strategic injection of brief bursts of real power can play a crucial role in maintaining grid reliability. Small-scale Superconducting Magnetic Energy Storage (SMES) systems, based on...

Astronomy

ASTRONOMY IN SPACE by Peter V. Mason, retired,  Jet Propulsion Laboratory, and Visiting Associate, California Institute of Technology. Pmason@alumni.caltech.edu In thinking about the reasons to perform astronomy in space, we first consider the effect of the earth’s atmosphere.  On a scale of decreasing energy, gamma rays, cosmic rays, X-rays and...

Cryocoolers

What is a Cryocooler? A mechanism that can extract heat from an object (cooler) and by doing so draw its temperature down below approximately 150 Kelvin (cryo). — (Courtesy Dr. Willy Gully) What is the difference between a Cryocooler and a Cryostat? A cryostat is any device designed to maintain...

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...