Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dark matter and particle acceleration in near space

10.11.2015

A new space telescope will soon peer into the darkness of 'near space' (within a few thousand light years of Earth) to seek answers related to the field of high-energy astrophysics

Peering into darkness can strike fear into the hearts of some, but a new space telescope will soon peer into the darkness of "near space" (within a few thousand light years of Earth). Scientists are using the telescope to seek answers related to the field of high-energy astrophysics.


The Japan Aerospace Exploration Agency (JAXA) Kounotori H-II Transfer Vehicle (HTV-5) is seen berthed to the International Space Station. The external CALET experiment, which will search for signatures of dark matter, is seen being extracted from the unpressurized section by the station's robotic arm, Canadarm2. An aurora over the Earth limb is visible in the background.

Credit: NASA

The CALorimetric Electron Telescope (CALET) investigation will rely on the instrument to track the trajectory of cosmic ray particles and measure their charge and energy. The instrument is optimized for measuring electrons and gamma rays, which may contain the signature of dark matter or nearby sources of high-energy particle acceleration.

"The investigation is part of an international effort (involving Japan, Italy and USA) to understand the mechanisms of particle acceleration and propagation of cosmic rays in the galaxy, to identify their sources of acceleration, their elemental composition as a function of energy, and possibly to unveil the nature of dark matter," said CALET principal investigator Dr. Shoji Torii.

"We know that dark matter makes up about a quarter of the mass-energy of the universe, but we can't see it optically and don't know what it is," said Dr. John Wefel, and CALET co-principal investigator for the US team. "If CALET can see an unambiguous signature of dark matter, it could potentially produce a new understanding of the nature of dark matter."

Right now, scientists are much more certain what dark matter is not, rather than what it is. This research may help scientists identify dark matter and fit it, more accurately, into standard models of the universe.

CALET launched aboard the Japan Aerospace Exploration Agency (JAXA) H-II Transfer Vehicle "Kounotori" (HTV-5) in August 2015 and was placed on the International Space Station's Japanese Experiment Module - Exposed Facility just days after its arrival.

The instrument is a charged particle telescope designed to measure electrons, protons, nuclei and gamma rays. Unlike the telescopes that are used to pinpoint stars and planets in the night sky, CALET operates in a scanning mode. As it looks upward, it records each cosmic ray event that enters its field of view and triggers its detectors to take measurements of the cosmic ray. These measurements are recorded on the space station and sent to a ground station where they are fed into computers running analysis codes that allow scientists to reconstruct each event.

From the resulting measurements, scientists must then separate electrons from the protons, gamma rays and the higher Z elements (chemical elements with >1 proton in the nucleus). They then sort the particles by energy to extend the existing data to higher energies and search for signatures of new astrophysics processes and phenomena like dark matter and nearby particle acceleration to study cosmic ray propagation in the galaxy.

"The major theoretical model attributes dark matter to weakly interacting massive particles (WIMPs), whose nature is predicted by various high energy physics models," said Torii. "In these models, a WIMP would be its own antiparticle and, when two of them get together, they annihilate, producing known particles like electron/positron pairs, proton/anti-proton pairs, and gamma rays."

Searching for excess annihilation products (i.e. electrons and gamma rays) is one way to try to identify a dark matter candidate and this is where CALET helps scientists. CALET joins another ISS investigation searching for excess annihilation products, the Alpha Magenetic Spectrometer or AMS, which is looking at positrons and antiprotons to identify dark matter.

"Dark matter is still a puzzle," said Torii. "By measuring with good energy resolution the spectrum of high energy cosmic electrons and photons, CALET may make a discovery or exclude existing models."

"Seeing an appropriate signature in the electron spectrum and/or gamma rays would be extremely important since this would set the mass scale (weight) for the dark matter particles, which would in turn allow theorists to better determine new physics associated with the WIMP," said Torii, adding that it is possible that a signature may be found that is not indicative of dark matter, but rather indicates a nearby source of charged particle acceleration.

"The latter would be [a] huge achievement since no individual sources have ever been positively identified," said Torii. "Such objects seem to be able to accelerate particles to energies far higher than we can achieve on Earth using the largest machines and we want to learn how nature does this, with possible applications here on Earth."

Understanding the location of these sources as well as particle propagation (the time particles spend, and distance traveled, wandering around the galaxy) means scientists can infer the shape of the cosmic ray spectrum at the source. Gaining a better understanding of how cosmic rays originate and the mechanisms of particle acceleration and propagation is important to space travel and for understanding the radiation environment in space and on Earth.

"Basically, CALET is after new information about how our little corner of the universe works," said Torii, who added that the investigation underscores the importance of the space station as a platform for performing investigations and for successful international collaboration.

Rachel Hobson | EurekAlert!

Further reports about: Earth Electrons NASA Space Center acceleration cosmic ray dark dark matter gamma rays spectrum

More articles from Physics and Astronomy:

nachricht Scientists reach back in time to discover some of the most power-packed galaxies
28.02.2017 | Clemson University

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

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: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Scientists reach back in time to discover some of the most power-packed galaxies

28.02.2017 | Physics and Astronomy

Nano 'sandwich' offers unique properties

28.02.2017 | Materials Sciences

Light beam replaces blood test during heart surgery

28.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>