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LIGO Detects Gravitational Waves for a Second Time

Scientists from the LIGO Scientific Collaboration have observed gravitational waves for a second time, according to an announcement made on June 15 during the 228th meeting of the American Astronomical Society in San Diego. The detection of the waves—ripples in the fabric of spacetime—was made on Dec. 25 by both...

EMIR Spectrograph Installed on Gran Telescopio CANARIAS

Engineers at the Roque de los Muchachos Observatory have attached the EMIR spectrograph to the Gran Telescopio CANARIAS (GTC), realizing a more than decade long design and fabrication process. The cryogenic instrument was designed, built, assembled and verified entirely at the IAC (Astrophysics Institute of Canrias). It will produce images...

FAST Research Accelerator Reaches Design Beam Energy

In May, Fermilab sent an electron beam with an energy of 50 million electronvolts, or MeV, through the photoinjector at the Fermilab Accelerator Science and Technology facility (FAST), achieving a major design goal for the accelerator and marking the beginning of a new accelerator science program at the laboratory.

New Elements Named, Public Comment Sought

The International Union of Pure and Applied Chemistry (IUPAC) has opened a five-month long public comment and review period of the names recommended for elements 113, 115, 117 and 118, the discoveries of which were announced late last year.

Scientists Use Frozen Argon to Boost Laser Light to New Extremes

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University and Louisiana State University have achieved a dramatic high harmonic generation (HHG) shift by shining an infrared laser through argon gas that’s been frozen at 20 K into a thin, fragile solid whose atoms barely cling to each...

New Low-Defect Method to Nitrogen Dope Graphene Results in Tunable Bandstructure

An interdisciplinary team of scientists at the US Naval Research Laboratory (NRL) Electronics Science and Technology and Materials Science and Technology Divisions has demonstrated hyperthermal ion implantation (HyTII) as an effective means of substitutionally doping graphene—a hexagonally-arranged single-atomic thickness carbon sheet—with nitrogen atoms. The result is a low-defect film with...

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Mixed Refrigerant Cycles

Most cryogenic refrigeration systems, both large scale systems and cryocoolers, use helium as a working fluid. There are a number of advantages to helium, not the least of which is that helium remains a fluid down to the lowest achievable temperatures. In order to freeze helium, pressures of over 20...

Fountain Pumps and He II Phase Separators

Helium II (He II), the second liquid phase of the 4He isotope described in this column in Cold Facts Spring 2010 (http://2csa.us/he2), can be modeled as consisting of two interpenetrating fluids. One, the superfluid component, has zero viscosity and entropy and the other, the normal fluid component, has nonzero viscosity...

Turboexpanders

A vital technology in the refrigerators and liquefiers described in Cold Facts Volume 31 Number 3 is that of turboexpanders. These devices are rotating machines in which the process fluid (e.g., helium) does work against the turboexpander while moving from high pressure to a lower pressure and thus is cooled....

Air Separation and Liquefaction

by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...

Bose-Einstein Condensate

A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...

Cold Technology for Pest Control

While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...

Cryogenic Finishing

The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...

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...