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‘Quantum critical’ theory gets experimental boost

New evidence this week supports a theory developed five years ago at Rice University to explain the electrical properties of several classes of materials -- including unconventional superconductors -- that have long vexed physicists.

Cryogenic testing completed for JWST mirrors

Cryogenic testing is complete for the final six primary mirror segments and a secondary mirror that will fly on NASA's James Webb Space Telescope. The milestone represents the successful culmination of a process that took years and broke new ground in manufacturing and testing large mirrors.

Scientists at Fermilab, Berkeley Lab build biggest maps of dark matter yet

Two teams of physicists at the U.S. Department of Energy's Fermilab and Lawrence Berkeley National Laboratory (Berkeley Lab) have independently made the largest direct measurements of the invisible scaffolding of the universe, building maps of dark matter using new methods that, in turn, will remove key hurdles for understanding dark...

Physicist builds the LHC, brick by LEGO brick

Physicist Sascha Mehlhase may have missed the actual construction of the ATLAS detector at CERN, but he found another way to experience the joy of building it – a way reminiscent of his childhood and the contents of a particularly good toy box he once had. He made the detector...

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Dilution Refrigerators

Dilution refrigerators are a common technique for reaching temperatures below 1K, particularly where continuous cooling at these temperatures is required. Helium exists in two stable isotopes: 4He and 3He. Naturally occurring 3He is extremely rare, constituting less than 1 part per million of helium gas. However, 3He can be manufactured,...

Oxygen Deficiency Hazards

Oxygen Deficiency Hazards (ODH) are a significant safety issue in cryogenic facilities. ODH occurs when inert gases such as nitrogen, helium or argon displace room air and thus lower the percentage of oxygen in the space below that required for human life. OSHA defines an area as oxygen deficient if...

Kelvin Temperature Scale

The Kelvin temperature scale is the principal temperature scale used in cryogenics and science. The kelvin is also one of the seven base units in the Système International d’Unités (SI) and is the unit of thermodynamic temperature. Thermodynamic temperature is a fundamental physical quantity (like mass, length or electrical current)...

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...