Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCI study finds dark matter is for superWIMPs

09.07.2003


New class of superweak particles may reveal secrets of hidden mass in universe

A UC Irvine study has revealed a new class of cosmic particles that may shed light on the composition of dark matter in the universe.

These particles, called superweakly interacting massive particles, or superWIMPs, may constitute the invisible matter that makes up as much as one-quarter of the universe’s mass.



UCI physicists Jonathan Feng, Arvind Rajaraman and Fumihiro Takayama report that these new superWIMPs have radically different properties from weakly interacting massive particles (WIMPs), which many researchers have long looked to as the leading dark matter candidate. The study was posted July 3 on the online version of Physical Review Letters (http://prl.aps.org/).

The identity of dark matter is one of the most puzzling problems for those who study the nature of our cosmos. While as much as a quarter of the universe is made of this invisible mass, which plays a vital role in the structure of the universe, almost nothing is known about its composition. It is believed to be the celestial glue that holds galaxies together in their distinctive spiral shapes.

To identify this elusive dark matter, many astrophysical researchers have turned to WIMPs. These particles emit no light and are very difficult to detect. However, as their name suggests, they do have weak-force interactions with other particles, and they are expected to leave visible traces in experiments. Currently, research groups throughout the world are searching for WIMPs, so far without success.

But in studying theories that predict WIMP dark matter, Feng and his colleagues found that in many of these theories WIMPs do not live forever. According to Feng, many theorists have assumed WIMPs to be the lightest particles and thus the most stable. “But we’ve found that WIMPs are often not stable at all, because they can decay into lighter particles,” Feng said, “and, all of a sudden, the WIMPs disappear.”

These new, lighter particles are superWIMPs. Like their progenitors, they emit no light and have both mass and gravitational force. But they are incapable of the type of weak-force interactions that WIMPs have; they can only interact gravitationally. Since the gravitational force is not as strong as the weak force, these interactions are, as Feng calls them, “superweak.” In turn, these particles will rarely, if ever, collide with other particles.

And, unlike WIMPs, superWIMPs are incapable of decaying into other particles. “They are absolutely stable,” Feng said. “And because of this, they are a completely different, but perfectly viable, alternative for dark matter.”

Like WIMPs, superWIMPs only exist theoretically. In fact, because superWIMPs do not have weak-force interactions, they are predicted to be impossible to detect by conventional experimental methods. But Feng and his colleagues point to some alternative tests to prove their existence. They found that observations of old stars and the cosmic microwave background of the universe can reveal clues for superWIMPs.

“One place to look for evidence is in the cosmic microwave background, which in essence is the afterglow of the Big Bang,” Feng said. “This background is very uniform. But according to our theory, WIMP decay would set loose a zoo of particles that would create deviations in this background. If such deviations are found, they would provide a particle fingerprint for the existence of superWIMP dark matter.”

Feng and his collaborators are currently investigating hints for superWIMPs in present data and are considering further studies that might provide evidence for the existence of superWIMP dark matter.

The research was funded by UC Irvine and a CAREER Award from the National Science Foundation.

Tom Vasich | UC Irvine
Further information:
http://prl.aps.org/
http://today.uci.edu/news/release_detail.asp?key=1009

More articles from Physics and Astronomy:

nachricht First quantum photonic circuit with electrically driven light source
27.09.2016 | Westfälische Wilhelms-Universität Münster

nachricht Australian technology installed on world’s largest single-dish radio telescope
26.09.2016 | International Centre for Radio Astronomy Research (ICRAR)

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: First quantum photonic circuit with electrically driven light source

Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.

Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

The Flexible Grid Involves its Users

27.09.2016 | Information Technology

Process-Integrated Inspection for Ultrasound-Supported Friction Stir Welding of Metal Hybrid-Joints

27.09.2016 | Machine Engineering

First quantum photonic circuit with electrically driven light source

27.09.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>