Do Supernovae Emit Gamma Rays in All Directions?

[Mike2]

Do all types of supernovae emit gamma rays? If so, is it an initial burst, or does the GRB last as long as the visible light? If so, is the GRB in all directions or just in jets? Thanks.

 

[Astronuc]

All stars emit gamma rays and X-rays, which is inherent in the nuclear and atomic processes within a plasma in which fusion takes place. Gamma rays bursts are simply an intense burst of gamma related to the extremely high power levels in the supernova phenomenon. It's possible that there is some direction dependence on gamma ray intensity, but off-hand I'm not sure what that would be.

The gamma rays burst/pulse should coincide with the visible light, but remember there is a distribution of frequencies and the peak shifts as a function of time. Visible light is emitted continuously.

See - http://science.nasa.gov/newhome/headlines/ast27jan99_1.htm

Jan 27, 1999: For the first time, scientists have witnessed the visible light emitted at the same time as a gamma-ray burst, a mysterious explosion in the far reaches of the universe.

The visible light is intense even after the GRB.
Caltech observes brightest gamma-ray burst so far
http://mr.caltech.edu/media/Press_Releases/PR11965.html

RACE TO GAMMA-RAY BURST REVEALS GIGANTIC EXPLOSION, DEATH & BIRTH
http://www.nasa.gov/centers/goddard/news/topstory/2003/0319hete.html

 

[Mike2]

Thanks. But what I'm really interested in is whether a nearby supernova could damage the ozone layer. The History channel resently had a show that described how a GRB might destroy the ozone layer and all the consequences that followed. Then I remembered a similar show narated by Patric Steward describing the same effects with a nearby supernova. I was just wondering how close a nearby supernova would have to be in order to cause those effects. Does anybody recall the show or know about such things? Thanks.

 

[mgb_phys]

For a regular supernova the distance is 10-20 light years. ie very very close in galactic terms, the 10,000 light years is for a GRB which are M times more energetic.

 

[Astronuc]

Thanks. But what I'm really interested in is whether a nearby supernova could damage the ozone layer. The History channel resently had a show that described how a GRB might destroy the ozone layer and all the consequences that followed. Then I remembered a similar show narated by Patric Steward describing the same effects with a nearby supernova. I was just wondering how close a nearby supernova would have to be in order to cause those effects. Does anybody recall the show or know about such things? Thanks.

There is certainly concern that a nearby SN could do a lot of damage to the Earth. One would have to determine a rad dosage that would damage the ozone layer or irradiate the Earth's surface, then use the source strength to determine the closest safe distance based on 1/r² reduction in strength.


Recently (Dec 27, 2004) there was a GRB, which was the brightest one recorded to date.

http://www.everything-science.com/content/view/111/98/en/

Scientists have detected a flash of light from across the Galaxy so powerful that it bounced off the Moon and lit up the Earth's upper atmosphere. This "giant flare" was the brightest explosion ever detected from beyond the Solar System. For over a tenth of a second the remarkable flare was actually brighter than a full moon.

NASA and European satellites and ground-based telescopes around the world detected the giant flare on 27 December 2004. Scientists from twenty institutes joined the observations. Two science teams report about this unprecedented event in an issue of Nature.

The light detected from the giant flare was far brighter in gamma rays than visible light or X-rays. It was probably created by an unprecedented eruption on the surface of an exotic neutron star which is classed both as an ultra-magnetic magnetar and as a soft gamma repeater (SGR). The designation of the neutron star that erupted is SGR 1806-20, about 50,000 light years from Earth in the constellation Sagittarius.

So it was in our solar system, 50 kly from earth.

http://en.wikipedia.org/wiki/SGR_1806-20

http://www.nasa.gov/vision/universe/watchtheskies/swift_nsu_0205.html

http://www.gsfc.nasa.gov/topstory/20021030strongestmag.html[/URL] ( 2 yrs before explosion of Dec 2004)

[I]An exceptionally bright flare from SGR 1806−20 and the origins of short-duration -ray bursts[/I]
[url]http://www.nature.com/nature/journal/v434/n7037/abs/nature03519.html[/url]

SGR 1806-20 Sudden Ionospheric Disturbance
[PLAIN]http://www.aavso.org/observing/programs/solar/sid-sgr1806.shtml[/URL]

SGR 1806-20 -- Pulsar
[url]http://simbad3.u-strasbg.fr/sim-id.pl?protocol=html&Ident=SGR+1806-20[/url]

Massive Stars in the SGR 1806-20 Cluster
http://adsabs.harvard.edu/abs/2005ApJ...622L..49F

 

[Astronuc]

Some other material of interest -

http://imagine.gsfc.nasa.gov/docs/science/know_l1/bursts.html

Using Swift observations of prompt and afterglow emission to classify GRBs
http://arxiv.org/abs/astro-ph/0701811


Long Burst Supernovae
http://www.nasa.gov/home/hqnews/2006/dec/HQ_06373_Hybrid_Burst.html

Hybrid GRB 060614: A Long Gamma-Ray Burst Without a Supernova
http://www.astro.caltech.edu/~avishay/grb060614.html

http://wise-obs.tau.ac.il/GRB030329/


ESA's INTErnational Gamma-Ray Astrophysics Laboratory is detecting some of the most energetic radiation that comes from space. It is the most sensitive gamma-ray observatory ever launched. INTEGRAL is an ESA mission in cooperation with Russia and the United States.

Diversity of the Supernova - Gamma-Ray Burst Connection by Nomoto, Tominaga, Tanaka, Maeda, Suzuki, Deng, and Mazzali. To be published in the proceedings of the conference "SWIFT and GRBs: Unveiling the Relativistic Universe", Venice, June 5-9, 2006. Should be in Il Nuovo Cimento

http://arxiv.org/abs/astro-ph/0702472

The connection between the long Gamma Ray Bursts (GRBs) and Type Ic Supernovae (SNe) has revealed interesting diversity. We review the following types of the GRB-SN connection. (1) GRB-SNe: The three SNe all explode with energies much larger than those of typical SNe, thus being called Hypernovae (HNe). They are massive enough for forming black holes. (2) Non-GRB HNe/SNe: Some HNe are not associated with GRBs. (3) XRF-SN: SN 2006aj associated with X-Ray Flash 060218 is dimmer than GRB-SNe and has very weak oxygen lines. Its progenitor mass is estimated to be small enough to form a neutron star rather than a black hole. (4) Non-SN GRB: Two nearby long GRBs were not associated SNe. Such 'dark HNe' have been predicted in this talk (i.e., just before the discoveries) in order to explain the origin of C-rich (hyper) metal-poor stars. This would be an important confirmation of the Hypernova-First Star connection. We will show our attempt to explain the diversity in a unified manner with the jet-induced explosion model.

Simulations of Magnetically-Driven Supernova and Hypernova Explosions in the Context of Rapid Rotation
http://arxiv.org/abs/astro-ph/0702539

Supernova Nucleosynthesis in Population III 13 -- 50 $M_{\odot}$ Stars and Abundance Patterns of Extremely Metal-Poor Stars
http://arxiv.org/abs/astro-ph/0701381

 

[Laura1013]

Did a Gamma-Ray Burst Initiate the Ordovician Extinction?
A. Melott et al.
American Physical Society, 2005
http://arxiv.org/abs/astro-ph/0309415