# Do supernovae emit gamma rays?

1. Oct 4, 2007

### 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.

2. Oct 5, 2007

### Astronuc

Staff Emeritus
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.

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 [Broken]

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

Last edited by a moderator: May 3, 2017
3. Oct 5, 2007

### 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.

4. Oct 5, 2007

### 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.

5. Oct 5, 2007

### Astronuc

Staff Emeritus
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.

Brightest Explosion Ever Observed Overwhelms Telescopes
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

Massive Stars in the SGR 1806-20 Cluster

Last edited by a moderator: May 3, 2017
6. Oct 5, 2007

### Astronuc

Staff Emeritus
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

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

7. Oct 7, 2007