Giant X-Ray Loop Hints at Cosmic Particle Accelerator

April 11, 2005
Giant X-Ray Loop Hints at Cosmic Particle Accelerator

Astronomers have found a vast loop-like structure, 20 light years across, adjacent to the most massive star-forming region known in our galaxy.
The loop, which was observed in X-ray wavelengths, is 15 times the size of the Arches Cluster, a star-forming region close to the centre of the Milky Way. This is the first time that such a distinctive and huge loop structure has been observed. Dr Masaaki Sakano, from the University of Leicester, will be presenting the discovery at the RAS National Astronomy Meeting at the University of Birmingham on Friday 8th April.

The team of astronomers, which includes scientists from the University of Leicester, CEA Saclay and the Max Planke Institute for Extraterrestrial Physics, observed the Arches Cluster repeatedly using the European X-ray satellite, XMM-Newton, as a part of the XMM-Newton Galactic Centre Survey. The galactic centre can only be observed at certain wavelengths, such as X-rays, because large amounts of dust lie in our line of sight and this blocks out optical light.

Dr Sakano says, "The X-ray spectrum of the loop is extraordinary. Most diffuse X-ray sources in the Universe have a characteristic temperature because they are the residual radiation from an event, such as a supernova explosion. However in this case the loop is non-thermal and this means that whatever the origin of the structure is, it is not stationary but rather the result of some ongoing process."

The most straightforward interpretation of the observations is that powerful particle-acceleration is occurring on-site, producing high energy particles with an energy of up to a thousand trillion electron volts (a thousand times more energetic than those produced in man-made particle accelerators). Such particles have been detected previously in a few supernova remnants and many pulsar nebulae, where a very powerful central source has created them. However, evidence for high-energy particles has never been observed before in star-forming regions of our galaxy.

At this stage it is not clear whether the loop structure is physically related to the Arches Cluster or just happens to be in our line of sight. However, if future observations show that the Arches Cluster is responsible for the feature, this discovery suggests that star-forming activity plays an important role in the energetic Universe.

Source: University of Leicester


Rank not rated yet
Tags

Relevant PhysicsForums posts

More news stories

Could Venus be shifting gear?

(PhysOrg.com) -- ESA’s Venus Express spacecraft has discovered that our cloud-covered neighbour spins a little slower than previously measured. Peering through the dense atmosphere in the infrared, the ...

Space & Earth / Space Exploration

created 22 hours ago | popularity 5 / 5 (7) | comments 8 | with audio podcast

Two new moons for Jupiter

Advances in technology have lead to the discovery of new planets outside of our Solar System, and now even new moons in our own backyard.

Space & Earth / Space Exploration

created 22 hours ago | popularity 4 / 5 (1) | comments 7

Mars Science Laboratory computer issue resolved

(PhysOrg.com) -- Engineers have found the root cause of a computer reset that occurred two months ago on NASA's Mars Science Laboratory and have determined how to correct it.

Space & Earth / Space Exploration

created 23 hours ago | popularity 4.7 / 5 (6) | comments 4 | with audio podcast

NASA sees wide-eyed cyclone Jasmine

Cyclone Jasmine's eye has opened wider on NASA satellite imagery, as it moves through the Southern Pacific Ocean.

Space & Earth / Earth Sciences

created 14 hours ago | popularity 3.5 / 5 (2) | comments 2

Clam fields found at deep, low-temperature Mariana vents

(PhysOrg.com) -- Scientists have marveled at the unusual life forms thriving at high temperature hydrothermal vents of the deep ocean.

Space & Earth / Earth Sciences

created 22 hours ago | popularity 4.3 / 5 (3) | comments 0 | with audio podcast


Anonymous knocks CIA website offline (Update)

The website of the Central Intelligence Agency was inaccessible on Friday after the hacker group Anonymous claimed to have knocked it offline.

New error-correcting codes guarantee the fastest possible rate of data transmission

Error-correcting codes are one of the triumphs of the digital age. They’re a way of encoding information so that it can be transmitted across a communication channel — such as an optical fiber o ...

Small modular reactor design could be a 'SUPERSTAR'

(PhysOrg.com) -- Though most of today's nuclear reactors are cooled by water, we've long known that there are alternatives; in fact, the world's first nuclear-powered electricity in 1951 came from a reactor ...

New power source discovered

(PhysOrg.com) -- Researchers at the Massachusetts Institute of Technology (MIT) and RMIT University have made a breakthrough in energy storage and power generation.

The power of estrogen -- male snakes attract other males

A new study has shown that boosting the estrogen levels of male garter snakes causes them to secrete the same pheromones that females use to attract suitors, and turned the males into just about the sexiest ...

Advanced power-grid model finds low-cost, low-carbon future in West

(PhysOrg.com) -- The least expensive way for the Western U.S. to reduce greenhouse gas emissions enough to help prevent the worst consequences of global warming is to replace coal with renewable and other ...