Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Observed: The outburst before the blast

07.02.2013
Before they go all-out supernova, certain large stars undergo a sort of "mini-explosion," throwing a good-sized chunk of their material off into space.

Though several models predict this behavior and evidence from supernovae points in this direction, actually observations of such pre-explosion outbursts have been rare. In new research led by Dr. Eran Ofek of the Weizmann Institute, scientists found such an outburst taking place a short time – just one month – before a massive star underwent a supernova explosion.

The findings, which recently appeared in Nature, help to clarify the series of events leading up to the supernova, as well as providing insight into the processes taking place in the cores of such massive stars as they progress toward the final stage of their lives.

Ofek, a member of the Institute's Particle Physics and Astrophysics Department, is a participant in the Palomar Transient Factory (PTF) project (led by Prof. Shri Kulkarni of the California Institute of Technology), which searches the skies for supernova events using telescopes at the Palomar Observatory in California. He and a research team from Israel, the UK and the US decided to investigate whether outbursts could be connected to later supernovae by combing for evidence of them in observations that predated PTF supernova sightings, using tools developed by Dr. Mark Sullivan of the University of Southampton.

The fact that they found such an outburst occurring just a little over a month before the onset of the supernova explosion was something of a surprise, but the timing and mass of the ejected material helped them to validate a particular model that predicts this type of pre-explosion event. A statistical analysis showed that there was only a 0.1% chance that the outburst and supernova were unrelated occurrences.

The exploding star, known as a type IIn supernova, began as a massive star, at least 8 times the mass of our sun. As such a star ages, the internal nuclear fusion that keeps it going produces heavier and heavier elements – until its core is mostly iron. At that point, the weighty core quickly collapses inward and the star explodes.

The violence and mass of the pre-explosion outburst they found, says Ofek, point to its source in the star's core. The material is speedily ejected from the core straight through the star's surface by the excitation of gravity waves. The researchers believe that continued research in this direction will show such mini-explosions to be the rule for this type of supernova.

Also participating in this research were Prof. Avishay Gal-Yam, Dr. Ofer Yaron and Iair Arcavi of the Institute's Particle Physics and Astrophysics Department, and Prof. Nir Shaviv of the Hebrew University of Jerusalem.

Prof. Avishay Gal-Yam's research is supported by the Helen and Martin Kimmel Award for Innovative Investigation; the Nella and Leon Benoziyo Center for Astrophysics; and the Lord Sieff of Brimpton Memorial Fund.

Dr. Eran Ofek's research is supported by the Willner Family Leadership Institute. Dr. Ofek is the incumbent of the Arye and Ido Dissentshik Career Development Chair.

The Weizmann Institute of Science in Rehovot, Israel, is one of the world's top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to 2,700 scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.

Weizmann Institute news releases are posted on the World Wide Web at http://wis-wander.weizmann.ac.il, and are also available at http://www.eurekalert.org.

Yivsam Azgad | EurekAlert!
Further information:
http://www.weizmann.ac.il

More articles from Physics and Astronomy:

nachricht Telescopes team up to find distant Uranus-sized planet through microlensing
31.07.2015 | NASA/Goddard Space Flight Center

nachricht California 'rain debt' equal to average full year of precipitation
31.07.2015 | 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: Quantum Matter Stuck in Unrest

Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.

What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...

Im Focus: On the crest of the wave: Electronics on a time scale shorter than a cycle of light

Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.

The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...

Im Focus: Superfast fluorescence sets new speed record

Plasmonic device has speed and efficiency to serve optical computers

Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.

Im Focus: Unlocking the rice immune system

Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight

A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...

Im Focus: Smarter window materials can control light and energy

Researchers in the Cockrell School of Engineering at The University of Texas at Austin are one step closer to delivering smart windows with a new level of energy efficiency, engineering materials that allow windows to reveal light without transferring heat and, conversely, to block light while allowing heat transmission, as described in two new research papers.

By allowing indoor occupants to more precisely control the energy and sunlight passing through a window, the new materials could significantly reduce costs for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Euro Bio-inspired - International Conference and Exhibition on Bio-inspired Materials

23.07.2015 | Event News

Clash of Realities – International Conference on the Art, Technology and Theory of Digital Games

10.07.2015 | Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

 
Latest News

Tool making and additive technology exhibition: Fraunhofer IPT at Formnext

31.07.2015 | Trade Fair News

First Siemens-built Thameslink train arrives in London

31.07.2015 | Transportation and Logistics

California 'rain debt' equal to average full year of precipitation

31.07.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>