Free Newsletter
Register for our Free Newsletters
Newsletter
Zones
Advanced Composites
LeftNav
Aerospace
LeftNav
Amorphous Metal Structures
LeftNav
Analysis and Simulation
LeftNav
Asbestos and Substitutes
LeftNav
Associations, Research Organisations and Universities
LeftNav
Automation Equipment
LeftNav
Automotive
LeftNav
Biomaterials
LeftNav
Building Materials
LeftNav
Bulk Handling and Storage
LeftNav
CFCs and Substitutes
LeftNav
Company
LeftNav
Components
LeftNav
Consultancy
LeftNav
View All
Other Carouselweb publications
Carousel Web
Defense File
New Materials
Pro Health Zone
Pro Manufacturing Zone
Pro Security Zone
Web Lec
Pro Engineering Zone
 
 
 
News

Chicago astrophysicist analyzing data from rare gamma-ray burst

University Of Chicago : 29 July, 2007  (Technical Article)
An artist
The birth cry of a black hole has startled Chicago astrophysicists and their colleagues who operate a NASA satellite that searches for gamma-ray bursts, the most powerful explosions in the universe.

The explosion occurred approximately 2 billion light years from Earth, too distant to pose a threat, but two and a half times closer than the next-closest burst for which scientists have reliable measurements.

“The chance of a burst this near and this bright happening is one in a few thousand,” said Don Lamb Jr., the Louis Block Professor in Astronomy & Astrophysics and the Mission Scientist for NASA’s High-Energy Transient Explorer-2 satellite. If such bursts are evenly distributed throughout the universe, he said, “we won’t see anything like this again.”

Follow-up observations by scientists at the Harvard-Smithsonian Center for Astrophysics quickly and, for the first time, clearly linked gamma-ray bursts and supernovae, which are exploding stars. This type of supernova results in the formation of a black hole, a compact object so dense that no light can escape its gravitational pull.

Lamb and his associates then confirmed the center’s finding using the Astrophysical Research Consortium 3.5-meter telescope at Apache Point Observatory in New Mexico.

“There have been clues and hints that gamma-ray bursts might be produced by core-collapse supernovae, but now it’s certain,” Lamb said.

The data suggest that the supernova explosion was non-spherical, which supports new ideas about how core collapse supernovae happen. “This is absolutely going to change everything,” Lamb said.

The cause of gamma-ray bursts has perplexed astrophysicists for the last three decades. Lasting anywhere from fractions of a second to many minutes, these unpredictable bursts occur almost daily and come from any direction in the sky. Afterglows, which are visible for a few days at X-ray and optical wavelengths, follow these bursts. HETE-2, launched in 2000, pinpoints burst locations within seconds so that ground telescopes can make crucial follow-up observations.

The burst lasted for more than 30 seconds. During this time it outshined the entire universe in gamma-ray emissions. Only two out of nearly 3,000 gamma-ray bursts that have been observed so far have shined more brightly since scientists discovered the phenomenon 30 years ago. Even the burst&s afterglow shined more than 10,000 times brighter than its host galaxy two hours after the burst occurred.

“The supernova component continues to outshine the host galaxy,” Lamb said. He expects that several more weeks will pass before the afterglow fades enough for astronomers to spot the host galaxy.

Once the afterglow fades for good, it will have brought together a marriage between the gamma-ray burst and supernova fields.

“The fields have been engaged for years now, but today I’m in the happy circumstance of witnessing them saying, ‘I do,” Lamb said.

Collaborating with Lamb on HETE-2 are Carlo Graziani, Senior Research Associate in Astronomy & Astrophysics, and Timothy Donaghy, a graduate student in Physics. Collaborating with him on the follow-up observations are Donald York, the Horace B. Horton Professor in Astronomy & Astrophysics and the College, and John Barentine, Russet McMillan, Jack Dembicky and Bill Ketzeback, observing specialists at Apache Point Observatory.
Bookmark and Share
 
Home I Editor's Blog I News by Zone I News by Date I News by Category I Special Reports I Directory I Events I Advertise I Submit Your News I About Us I Guides
 
   Â© 2012 NewMaterials.com
Netgains Logo