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
Joan Font: email@example.com
John Beckman: firstname.lastname@example.org
Alejandra Rueda Moral | EurekAlert!
Cold molecules on collision course
13.10.2017 | Max-Planck-Institut für Quantenoptik
The LBT gets polarized: First light for the PEPSI polarimeters
13.10.2017 | Leibniz-Institut für Astrophysik Potsdam
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...
Mercury, our smallest planetary neighbor, has very little to call an atmosphere, but it does have a strange weather pattern: morning micro-meteor showers.
Recent modeling along with previously published results from NASA's MESSENGER spacecraft -- short for Mercury Surface, Space Environment, Geochemistry and...
The two Academy presidents Chunli Bai and Anton Zeilinger tested quantum encrypted communication between Beijing and Vienna in a live-experiment. The quantum key was transmitted via the Chinese quantum satellite Micius.
From quantum cryptography to the quantum internet – fundamental research into the world of the quantum promises several new tech opportunities in the future....
10.10.2017 | Event News
10.10.2017 | Event News
28.09.2017 | Event News
13.10.2017 | Physics and Astronomy
13.10.2017 | Trade Fair News
13.10.2017 | Physics and Astronomy