Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mass Map Shines Light on Dark Matter

16.07.2015

Dark matter may find it tougher to hide in our universe.

An international team of researchers has developed a new map of the distribution of dark matter in the universe using data from the Dark Energy Survey (DES).


Image courtesy Vinu Vikraman / Argonne National Laboratory

By cross-correlating a galaxy distribution map and a mass map derived from weak gravitational lensing, a team of researchers that included Argonne National Laboratory’s Vinu Vikraman showed how the galaxy distribution traces that of the dark matter.

The DES, underway at the Blanco telescope in Chile, is a cosmological galaxy survey that will map approximately an eighth of the visible sky. The primary aim of the DES is to better characterize dark energy – the source of the observed accelerated expansion of the universe.

But one of the ways of doing this is through studying the distribution and evolution of another scientific mystery: dark matter. Scientists estimate that ordinary atomic matter makes up only one-fifth of the total mass in the universe. The remaining mass is dark – “dark” because it does not absorb or emit light.

Scientists need a precise measurement of all the matter in the universe and where it is located to perform cosmological experiments accurately, said Vinu Vikraman, a postdoctoral researcher at the U.S. Department of Energy’s Argonne National Laboratory and co-author of the study.

“We don’t know what dark matter really is or how to directly locate it in the universe,” Vikraman said. “This map will act as a valuable tool for cosmology to answer some of these questions, including those related to dark energy.”

To indirectly detect dark matter, the scientists constructed a “mass map” using weak gravitational lensing shear measurements made by the DES. Gravitational lensing refers to the bending of light by the mass surrounding galaxies. This bending creates a distortion, or shear, of the galaxy’s shape, which scientists can then measure to determine the density and matter distribution of the lens.

The researchers then compared the mass map with a new optical galaxy distribution map, also made from DES data. The information allowed the scientists to look for patterns in the distribution of galaxies and dark matter.

“It also allows us to check our work,” Vikraman said, “since the distribution of galaxies is expected to trace the distribution of dark matter.”

The relationship between the galaxy distribution and the mass map is close to that predicted by theoretical models based on cosmological simulations that include an accelerated expansion of the universe.

DES data are projected to cover more than 36 times the area of this initial map. Scientists are hopeful that this set of data will lead to new clues about the nature of dark energy.

The research appears in two papers, Vikram et al., “Wide-Field Lensing Mass Maps from the DES Science Verification Data: Methodology and Detailed Analysis,” in Physical Review D (in press) and Chang et al., “Wide-Field Lensing Mass Maps from DES Science Verification Data,” published June 24 in Physical Review Letters. The U.S. Department of Energy’s Office of Science, the National Science Foundation and the collaborating institutions in the DES funded the study.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov/.

By Sarah Schlieder

Contact Information
Louise Lerner
Argonne National Laboratory
media@anl.gov
Phone: 630-252-5526

Louise Lerner | newswise
Further information:
http://www.anl.gov

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>