The search will be conducted with a recently retooled, extremely sensitive detector that is currently in a testing and shakeout phase at the University of Washington's Center for Experimental Nuclear Physics and Astrophysics.
The axion was first conjectured by physicists in the late 1970s as a solution to a problem in a theory called quantum chromodynamics. Little is known for sure about the axion. It appears to react gravitationally to matter, but otherwise it seems to have no other interaction.
Since the 1930s, scientists have believed there must be some unseen but massive substance, a sort of gravitational glue, that prevents rotating galaxies from spinning apart. Axions, if they in fact do exist, are candidates for the makeup of cold dark matter that would act as that gravitational glue.
Dark matter is believed to account for about one-quarter of all the mass in the universe. However, because axions react so little – and the reactions they are likely to produce are so faint – finding them is tricky.
"We have probably the most sensitive axion detector in operation," Rosenberg said. "It looks for the incredibly feeble interaction between the axion and electromagnetic radiation."
The aim of the Axion Dark Matter Experiment is to search for cold dark matter axions in the halo of the Milky Way galaxy by detecting the very weak conversion of axions into microwave photons.
The detector employs a powerful magnet surrounding a sensitive microwave receiver that is supercooled to 4.2 kelvins, or about minus-452 F. Such low temperature reduces thermal noise and greatly increases the chance that the detector will actually see axions converting to microwave photons.
The microwave receiver can be fine-tuned to the axion mass, which also increases the possibility of detecting an interaction between axions and the detector's magnetic field. A reaction would deposit a minuscule amount of electromagnetic power into the receiver, which could be recorded by computers monitoring the detector.
There have been previous efforts to locate the axion, but there is greater interest in the Axion Dark Matter Experiment because of recent developments in physics research. The most notable is that the Large Hadron Collider near Geneva, Switzerland, lauded for its discovery of the elusive Higgs boson in 2012, did not find evidence to support supersymmetry, a proposed resolution for some inconsistencies among theories of particle physics.
That lack of evidence provided impetus to separate the search for dark matter from work on supersymmetry, Rosenberg said, so the newest version of the Axion Dark Matter Experiment is drawing substantial interest among researchers.
"This is a needle-in-a-haystack experiment. Once we find the needle, we can stop immediately," Rosenberg said.
"We could find it in our first week of data-taking, our last week of data-taking, or never."
Assembly of the detector was completed in early October, and the team has begun weeks to months of commissioning, which involves testing and fine-tuning the equipment. Then the hunt will begin in earnest.
Collaborators in the research come from Lawrence Livermore National Laboratory; the National Radio Astronomy Observatory; the University of California, Berkeley; the University of Sheffield in England; the University of Florida; and Yale University. The work is funded by the Department of Energy.
For more information, contact Rosenberg at 206-221-5856 or email@example.com
Vince Stricherz | Newswise
When helium behaves like a black hole
22.03.2017 | University of Vermont
Astronomers hazard a ride in a 'drifting carousel' to understand pulsating stars
22.03.2017 | International Centre for Radio Astronomy Research
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
22.03.2017 | Materials Sciences
22.03.2017 | Physics and Astronomy
22.03.2017 | Materials Sciences