Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New technique reveals supernova progenitor

22.05.2014

Wolf-Rayet stars are very large and very hot. Astronomers have long wondered whether Wolf-Rayet stars are the progenitors of certain types of supernovae. New work from the Palomar Transient Factory team, including Carnegie's Mansi Kasliwal, is homing in on the answer. They have identified a Wolf-Rayet star as the likely progenitor of a recently exploded supernova. This work is published by Nature.

Wolf-Rayet stars are notable for having strong stellar winds and being deficient in hydrogen when compared with other stars. Taken together, these two factors give Wolf-Rayet stars easily recognizable stellar signatures.

It is thought that Wolf-Rayet stars explode as type IIb, Ib or Ic supernovae. Yet, direct evidence linking these types of supernovae to their progenitor stars has heretofore been missing.

The team, led by Avishay Gal-Yam of the Weizmann Institute of Science in Israel, applied a novel observational method called flash spectroscopy to identify the likely progenitor of a type IIb supernova called SN 2013cu just over 15 hours after it exploded.

"This supernova was discovered by the Palomar 48-inch telescope in California. The on-duty PTF team member in Israel promptly sounded an alert about this supernova discovery enabling another PTF team member to get a spectrum with the Keck telescope before the sun rose in Hawaii," Kasliwal explained. "The global rapid response protocol ensures the sun never rises for the PTF team!"

When the supernova exploded, it flash ionized its immediate surroundings, giving the astronomers a direct glimpse of the progenitor star's chemistry. This opportunity lasts only for a day before the supernova blast wave sweeps the ionization away. So it's crucial to rapidly respond to a young supernova discovery to get the flash spectrum in the nick of time.

The observations found evidence of composition and shape that aligns with that of a Nitrogen-rich Wolf-Rayet star. What's more, the progenitor star likely experienced an increased loss of mass shortly before the explosion, which is consistent with model predictions for Wolf-Rayet explosions. These techniques shed fresh light on the poorly understood evolution of massive stars.

Previously when looking for a pre-explosion star using the Hubble Space Telescope, astronomers could only look over a range of about 20 megaparsecs. But using these new tools they can increase that distance by a factor of five, allowing them to identify many more supernovae progenitors.

###

The Palomar Transient Factory collaboration is led by Shri Kulkarni of the California Institute of Technology. PTF has discovered more than 2000 supernovae during its four and a half years of observations, including many rare and exotic types of cosmic outbursts.

This research was supported by the I-CORE Program \The Quantum Universe" of the Planning and Budgeting Committee and The Israel Science Foundation; grants from the ISF, BSF, GIF, Minerva, the FP7/ERC, and a Kimmel Investigator award.; support from the Hubble and Carnegie-Princeton Fellowships; support from the Arye Dissentshik career development chair and a grant from the Israeli MOST; support from the NSF; support from an NSF Postdoctoral Fellowship; support from the TABASGO Foundation, the Christopher R. Redlich Fund, and NSF grant AST-1211916. The National Energy Research Scientific Computing Center, supported by the Office of Science of the U.S. Department of Energy, provided staff, computational resources, and data storage for this project.

The intermediate Palomar Transient Factory (iPTF)—led by the California Institute of Technology (Caltech)—started searching the skies for certain types of stars and related phenomena in February. The iPTF was built on the legacy of the Palomar Transient Factory (PTF), designed in 2008 to systematically chart the transient sky by using a robotic observing system mounted on the 48-inch Samuel Oschin Telescope on Palomar Mountain near San Diego, California. iPTF is a scientific collaboration among the California Institute of Technology, Los Alamos National Laboratory, the University of Wisconsin, Milwaukee, the Oskar Klein Center, the Weizmann Institute of Science, the TANGO Program of the University System of Taiwan, and the Kavli Institute for the Physics and Mathematics of the Universe.

The Carnegie Institution for Science is a private, nonprofit organization headquartered in Washington, D.C., with six research departments throughout the U.S. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.

Mansi Kasliwal | Eurek Alert!

Further reports about: Carnegie Factory Hubble NSF PTF Palomar Telescope progenitor supernovae technique

More articles from Physics and Astronomy:

nachricht The dark side of the fluffiest galaxies
24.05.2016 | Instituto de Astrofísica de Canarias (IAC)

nachricht Astronomers confirm faintest early-universe galaxy ever seen
24.05.2016 | University of California - Los Angeles

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: Atomic precision: technologies for the next-but-one generation of microchips

In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.

In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...

Im Focus: Researchers demonstrate size quantization of Dirac fermions in graphene

Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices

Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.

Im Focus: Graphene: A quantum of current

When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene

In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...

Im Focus: Transparent - Flexible - Printable: Key technologies for tomorrow’s displays

The trend-forward world of display technology relies on innovative materials and novel approaches to steadily advance the visual experience, for example through higher pixel densities, better contrast, larger formats or user-friendler design. Fraunhofer ISC’s newly developed materials for optics and electronics now broaden the application potential of next generation displays. Learn about lower cost-effective wet-chemical printing procedures and the new materials at the Fraunhofer ISC booth # 1021 in North Hall D during the SID International Symposium on Information Display held from 22 to 27 May 2016 at San Francisco’s Moscone Center.

Economical processing

Im Focus: Trojan horses for hospital bugs

Staphylococcus aureus usually is a formidable bacterial pathogen. Sometimes, however, weakened forms are found in the blood of patients. Researchers of the University of Würzburg have now identified one mutation responsible for that phenomenon.

Staphylococcus aureus is a bacterium that is frequently found on the human skin and in the nose where it usually behaves inconspicuously. However, once inside...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking 4.0: International Laser Technology Congress AKL’16 Shows New Ways of Cooperations

24.05.2016 | Event News

Challenges of rural labor markets

20.05.2016 | Event News

International expert meeting “Health Business Connect” in France

19.05.2016 | Event News

 
Latest News

Rutgers scientists help create world's largest coral gene database

24.05.2016 | Earth Sciences

New technique controls autonomous vehicles on a dirt track

24.05.2016 | Information Technology

Programmable materials find strength in molecular repetition

24.05.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>