Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA 'dark matter' conference highlights new research on mysterious cosmic substance

26.02.2010
UCLA scientists to discuss XENON100, the newest dark matter detector

Dark matter, for more than 70 years as mysterious and unknowable a subject to science as the legendary island of Atlantis has been to history, is bringing 140 scientists from the U.S., Europe and Asia to the Marriott Hotel in Marina del Rey for the ninth UCLA Symposium on Sources and Detection of Dark Matter and Dark Energy in the Universe. The three-day conference runs through Friday, Feb. 26.

"Dark matter is one of the last great frontiers in science," said David B. Cline, UCLA professor of physics, high-energy astrophysicist and symposium organizer. "Once we know what it really is, we will break through into a new realm of nature. It's going to be an entirely new era for science, it's going to pose fascinating new questions, it's going to be exciting."

First proposed in the 1930s by the late California Institute of Technology scientist Fritz Zwicky to explain why some galaxies appeared more ponderous than their luminosity would suggest, dark matter is thought to account for almost 25 percent of the universe today. Just 5 percent is made up of visible, tangible matter; the remaining 70 percent is in the equally baffling form of dark energy. Despite its abundance, uncontested reality and ubiquity, dark matter has so far evaded direct observation.

At the symposium, scientists will discuss a range of topics, from tantalizing hints of dark matter gleaned from a dozen or so experiments currently underway around the world, to more sophisticated detectors that will perhaps reveal at last the true identity of this mysterious stuff, to considerations of a still deeper and more profound stratum in nature.

UCLA professor of physics Katsushi Arisaka and Hanguo Wang, a UCLA physics researcher, will describe the newest dark matter detector, XENON100, which UCLA has been operating beneath Italy's Gran Sasso mountain, some 70 miles west of Rome, in partnership principally with Columbia University and Rice University, along with seven other institutions in Switzerland, Portugal, Italy, Germany, France, Japan and China.

The XENON100 detector is an instrumented vat, about the size of a stockpot — 12 inches in diameter and 12 inches tall — holding 220 pounds of frigid liquid xenon. It is, in effect, a traffic surveillance camera that can record the occasional, if very infrequent, collision between a dark matter particle and a xenon atom.

There is a certain irony to this, given that xenon is a heavy, noble gas that does not react easily with other elements and yet is the target of choice for subatomic particles that themselves are very aloof. But both are large entities in their respective realms, the physicists reason, and so are bound to collide sooner or later. And when they do, the UCLA team believes the XENON100 detector will capture the event through signals that only a xenon–dark matter collision can produce.

Dark matter is widely thought to be a kind of massive elementary particle that interacts weakly, when it interacts at all, with ordinary matter; physicists call these particles WIMPs, for weakly interacting massive particles.

WIMPs are everywhere throughout the universe, streaming constantly through the Milky Way galaxy, the solar system, Earth's atmosphere, mountains — and even cylinders filled with liquid xenon. And when the occasional WIMP does bump into a xenon molecule, the xenon atom recoils and emits a tiny flash of scintillation, or light. The bump also causes the struck xenon to give off a small burst of ionizing radiation.

Both signals fall on an array of small, sensitive sensors — "avalanche photon-intensifying devices," so-called because a single scintillating flash sets off a cascade of electrons into the instrument's recorders. Imagine the sound of a pin dropped on a marble counter instantly transformed into booms of a bass drum and you begin to appreciate the effectiveness of these sensors.

Cline praised Arisaka and Wang for the way they integrated these sensors into the overall XENON100 detector, saying that the devices can discriminate between those signals triggered by dark matter and those triggered by gamma rays and naturally occurring radioactive elements in Gran Sasso mountain.

As proud as they are of the XENON100 instrument and its performance to date — indeed, even before they know definitively if they have caught sight of one or more WIMPs — the UCLA team is working on bigger, more sensitive dark matter detectors. A XENON1000 device, 10 times larger than the one now operating, would provide a 100-times larger arena, and much greater opportunities, for WIMPs and xenon to collide, for confirming test results to be gathered and for the unraveling of dark matter to begin.

For more information about the UCLA symposium, visit www.physics.ucla.edu/hep/dm10/index.html.

UCLA is California's largest university, with an enrollment of nearly 38,000 undergraduate and graduate students. The UCLA College of Letters and Science and the university's 11 professional schools feature renowned faculty and offer more than 323 degree programs and majors. UCLA is a national and international leader in the breadth and quality of its academic, research, health care, cultural, continuing education and athletic programs. Five alumni and five faculty have been awarded the Nobel Prize.

For more news, visit the UCLA Newsroom and follow us on Twitter.

Stuart Wolpert | EurekAlert!
Further information:
http://www.ucla.edu

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>