Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UMass Amherst physicists contribute to dark matter detector success

22.02.2018

In the quest for evidence of dark matter, physicist Andrea Pocar of UMass Amherst and his students have played a role in designing and building a part of the argon-based DarkSide-50 detector in Italy.

In researchers' quest for evidence of dark matter, physicist Andrea Pocar of the University of Massachusetts Amherst and his students have played an important role in designing and building a key part of the argon-based DarkSide-50 detector located underground in Italy's Gran Sasso National Laboratory.


Undergraduate Arthur Kurlej welding the grid electrode onto its support ring inside the radon-suppressed clean room in the underground laboratory at Gran Sasso, Italy. Kurlej's advisor, physics professor Andrea Pocar, says undergraduates were notably helpful in designing and making this component of the dark matter detector there, known as DarkSide-50.

Credit: UMass Amherst

This week, scientists from around the world who gathered at the University of California, Los Angeles, at the Dark Matter 2018 Symposium learned of new results in the search for evidence of the elusive material in Weakly Interacting Massive Particles (WIMPs) by the DarkSide-50 detector. WIMPs have been candidate dark matter particles for decades, but none have been found to date.

Pocar says the DarkSide detector has demonstrated the great potential of liquid argon technology in the search for so-called "heavy WIMPs," those with mass of about 100 to 10,000 times the mass of a proton. Further, he adds, the double-phase argon technique used by the DarkSide-50 detector has unexpected power in the search for "low-mass WIMPs," with only 1-10 times the mass of a proton.

He adds, "The component we made at UMass Amherst, with very dedicated undergraduates involved from the beginning, is working very well. It's exciting this week to see the first report of our success coming out at the symposium." His graduate student Alissa Monte, who has studied surface and radon-related backgrounds using DarkSide-50, will present a poster at the UCLA meeting.

Pocar says, "There is a vibrant community of researchers around the world conducting competing experiments in this 'low mass' WIMP area. Over the past two years we collected data for a measurement we didn't expect to be able to make. At this point we are in a game we didn't think we could be in. We are reporting the high sensitivity we have achieved with the instrument, which is performing better than expected." Sensitivity refers to the instrument's ability to distinguish between dark matter and background radiation.

Dark matter, Pocar explains, represents about 25 percent of the energy content of the universe and while it has mass that can be inferred from gravitational effects, physicists have great difficulty detecting and identifying it because it hardly interacts, if at all, with "regular" matter through other forces. "Dark matter doesn't seem to want to interact much at all with the matter we know about," the physicist notes.

The DarkSide-50 detector uses 50 kg (about 110 lbs.) of liquid argon in a vat, with a small pocket of argon gas at the top, Pocar explains, as a target to detect WIMPs. The researchers hope for a WIMP to hit the nucleus of an argon atom in the tank, which then can be detected by the ionization produced by the nuclear recoil in the surrounding argon medium. Some of the ionization signal, proportional to the energy deposited inside the detector, is collected by applying an electric field to the target, he explains.

A flash of light is also produced in the argon with ionization, Pocar says. For high-enough energy events, the light pulse is bright enough to be used to tell the difference in "signature" between a nuclear recoil like that induced by a WIMP, and electron recoils induced by background or environmental radioactivity.

Pocar's lab designed, made and installed one of the electrodes that apply the electric field. He says, "For low-mass WIMPs, the amount of energy transmitted to the nucleus of argon by a WIMP is incredibly tiny. It's like hitting a billiard ball with a slow ping-pong ball. But a key thing for us is that now with two years of data, we have an exquisite understanding of our detector and we understand all non-WIMP events very well. Once you understand your detector, you can apply all that understanding in search mode, and plan for follow-up experiments."

Cristiano Galbiati, spokesperson for the DarkSide project, said at this week's symposium, "This is the best way to start the adventure of the future experiment DarkSide-20k. The results of DarkSide-50 provide great confidence on our technological choices and on the ability to carry out a compelling discovery program for dark matter. If a detector technology will ever identify convincingly dark matter induced events, this will be it."

###

The DarkSide-50 apparatus and experiments are supported by the Italian National Institute for Nuclear Physics, which operates the Gran Sasso Laboratory, the U.S. National Science Foundation, and funding agencies at collaborating institutions in Brazil, China, France, Poland, Spain and Russia.

Media Contact

Janet Lathrop
jlathrop@umass.edu
413-545-2989

 @umassscience

http://www.umass.edu 

 

Janet Lathrop | EurekAlert!

Further reports about: Laboratory Nuclear Physics dark matter detector electric field ionization

More articles from Physics and Astronomy:

nachricht Manifestation of quantum distance in flat band materials
05.08.2020 | Institute for Basic Science

nachricht First radio detection of an extrasolar planetary system around a main-sequence star
04.08.2020 | Max-Planck-Institut für Radioastronomie

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: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

Im Focus: NYUAD astrophysicist investigates the possibility of life below the surface of Mars

  • A rover expected to explore below the surface of Mars in 2022 has the potential to provide more insights
  • The findings published in Scientific Reports, Springer Nature suggests the presence of traces of water on Mars, raising the question of the possibility of a life-supporting environment

Although no life has been detected on the Martian surface, a new study from astrophysicist and research scientist at the Center for Space Science at NYU Abu...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Manifestation of quantum distance in flat band materials

05.08.2020 | Physics and Astronomy

Discovery shows promise for treating Huntington's Disease

05.08.2020 | Health and Medicine

Rock debris protects glaciers from climate change more than previously known

05.08.2020 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>