Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Astronomers use IAC instrument to probe the origins of cosmic rays

10.10.2017

The study, published in the Astrophysical Journal, is based on observations of the expanding remnant of Tycho's supernova

In November 1572 a supernova explosion was observed in the direction of the constellation of Cassiopeia, and its most famous observer was Tycho Brahe, one of the founders of modern observational astronomy.


Left. Composite image of the remnant of Tycho Brahe's supernova (1572) using data from the Chandra x-ray satellite observatory (yellow, green, blue (credits NASA/SAO), from the Spitzer infrared satellite observatory (red, credits, NASA/JPL-Caltech), and from the Calar Alto observatory (stars whtie, credit, Krause et al.). The transparent magenta box shows the field of the ACAM instrument at the Cassegrain focus of the William Herschel Telescope (WHT, ORM, La Palma). Centre, a zoom-in on the ACAM field with a green box showing the size of the field of the 2d spectrograph GHaFaS (WHT, ORM).Right. The reduced and integrated image of GHaFaS in the emission from ionized hydrogen (Ha).

Credit: NASA/SAO, NASA/JPL-Caltech

The explosion produced an expanding cloud of superhot gas, a supernova remnant which was rediscovered in 1952 by British radioastronomers, confirmed by visible photographs from Mount Palomar observatory, California, in the 1960's, and a spectacular image was taken in X-rays by the Chandra satellite observatory in 2002 (see accompanying image). Astronomers use supernova remnants to explore high energy physics in interstellar space.

In an article to be published in the Astrophysical Journal a team from 7 countries, including researchers at the Instituto de Astrofísica de Canarias (IAC), has observed the Tycho supernova remnant with GHaFaS, a sophisticated instrument from the IAC, mounted on the 4.2m William Herschel Telescope (WHT) at the Roque de los Muchachos Observatory (Garafía, La Palma, Canary Islands).

Their aim was to explore the hypothesis that the cosmic rays, high energy sub-atomic particles which continually bombard the Earth's outer atmosphere, originate in these highly energetic gas clouds. GHaFaS allows astronomers to observe the emission from ionized hydrogen across wide fields, giving a map of the velocity structure within an object in fine detail.

They mapped a sizeable portion of the Tycho remnant cloud, including a prominent bright filament, and showed that the hydrogen line emitted from the filament shows a much bigger spread of velocities than can be explained from the temperature of the gas. In fact they measured two components of emission, one with a large velocity spread, and another with an even larger spread.

They showed that the only way for the emission to show these characteristics is if there is a mechanical mechanism in the cloud producing high energy particles. Supernova remnants have long been considered a probable source of the cosmic rays which pour onto the outer atmosphere of the Earth, but this is the first time that clear evidence for an acceleration mechanism has been produced.

Cosmic rays have energies much higher than those produced in even the biggest particle accelerators on Earth (such as CERN), and their study is important not only for astrophysics but for particle physics.

"These results could not have been produced by any of the other spectrographs on major telescopes in the world" says Joan Font, one of the authors of the article, and the person responsible for the operations of GHaFaS. "Our instrument has a unique combination of high velocity resolution, wide field, and good angular resolution, and this combination was required for the Tycho project".

These observations are a first step towards a fuller understanding of the cosmic ray acceleration mechanism in supernova remnants. "We should be able to combine these results with observations already taken using the OSIRIS narrow band imager on the 10.4m Gran Telescopio CANARIAS (GTC) to determine the efficiency of acceleration of the cosmic rays" says John Beckman, another IAC researcher and a co-author on the paper.

###

Article: "Balmer filaments in Tycho's supernova remnant: an interplay between cosmic-ray and broad-neutral precursors". Sladjana Kneevi et al 2017 ApJ 846 167

https://doi.org/10.3847/1538-4357/aa8323

Contact:

Joan Font: jfont@iac.es

John Beckman: jeb@iac.es

Media Contact

Alejandra Rueda Moral
arueda@iac.es

http://www.iac.es/?lang=en 

Alejandra Rueda Moral | EurekAlert!

More articles from Physics and Astronomy:

nachricht A better way to weigh millions of solitary stars
15.12.2017 | Vanderbilt University

nachricht A chip for environmental and health monitoring
15.12.2017 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>