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 Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

nachricht NASA's fermi finds possible dark matter ties in andromeda galaxy
22.02.2017 | NASA/Goddard Space Flight Center

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>