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 New method gives microscope a boost in resolution
10.12.2018 | Rudolf-Virchow-Zentrum für Experimentelle Biomedizin der Universität Würzburg

nachricht A new 'spin' on kagome lattices
10.12.2018 | Boston College

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: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Small but ver­sat­ile; key play­ers in the mar­ine ni­tro­gen cycle can util­ize cy­anate and urea

10.12.2018 | Life Sciences

New method gives microscope a boost in resolution

10.12.2018 | Physics and Astronomy

Carnegie Mellon researchers probe hydrogen bonds using new technique

10.12.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>