Feeds

Cosmic ray source riddle mystery now even more mysterious

Eggheads stumped after killer gamma rays ruled out. Probably

Intelligent flash storage arrays

Boffins are now even more puzzled about where high-energy cosmic rays come from after a new study showed that gamma ray bursts are probably not to blame.

Cosmic rays hitting Earth

Cosmic rays hitting Earth. Credit: NSF/J. Yang

Astroboffins only had two theories about what causes cosmic rays, which regularly penetrate Earth's atmosphere: huge explosions out in space or supermassive black holes.

Now an international group, made up of no fewer than 250 physicists and engineers, says that the suspected gamma radiation bursts are unlikely to be the source for cosmic rays because they couldn't find any neutrinos emitted from the mother-of-all space bangs they observed.

Cosmic rays are electrically charged subatomic particles with energies of up to one hundred million times more than those created in manmade accelerators such as the Large Hadron Collider. A gamma ray, meanwhile, is high-energy electromagnetic radiation that's harmful to life.

Using the IceCube Neutrino Observatory at the South Pole in Antarctica, the boffins watched 300 gamma ray bursts (GRBs) while searching for the neutrinos that are believed to be linked with cosmic ray generation, and found none.

"The result of this neutrino search is significant because for the first time we have an instrument with sufficient sensitivity to open a new window on cosmic ray production and the interior processes of GRBs," said IceCube spokesperson and University of Maryland physics professor Greg Sullivan in a canned statement.

"The unexpected absence of neutrinos from GRBs has forced a re-evaluation of the theory for production of cosmic rays and neutrinos in a GRB fireball and possibly the theory that high energy cosmic rays are generated in fireballs."

The IceCube laboratory

The IceCube observatory spots neutrinos by the faint blue light they produce when they interact with ice. It's basically a cubic kilometre of glacial ice equipped with more than 5,000 optical sensors.

This is the best way to "see" neutrinos because they can easily pass through other matter, including people or the whole planet, without leaving a trace.

Of course, being scientists, this study's boffins aren't willing to completely bin the GRB theory yet - instead they're getting the IceCube detector to collect more data first.

"Although we have not discovered where cosmic rays come from, we have taken a major step towards ruling out one of the leading predictions," said IceCube's principal investigator Francis Halzen of the University of Wisconsin.

The study was published today in Nature. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
SECRET U.S. 'SPACE WARPLANE' set to return from SPY MISSION
Robot minishuttle X-37B returns after almost 2 years in orbit
LOHAN crash lands on CNN
Overflies Die Welt en route to lively US news vid
'Utter killjoy Reg hacks have NEVER BEEN LAID', writes a fan
'Shuddit, smarty pants!' Some readers reacted badly to our last Doctor Who review ...
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
Carry On Cosmonaut: Willful Child is a poor taste Star Trek parody
Cringeworthy, crude and crass jokes abound in Steven Erikson’s sci-fi debut
White LED lies: It's great, but Nobel physics prize-winning great?
How artificial lighting could offer an artificial promise
Origins of SEXUAL INTERCOURSE fished out of SCOTTISH LAKE
Fossil find proves it first happened 385 million years ago
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.