[ RadSafe ] Re: the magnetar eruption

[bobcherry at cox.net]

I have the erg to tell Andy he is a joule of a fellow!

Bob C

> 
> From: "A  Karam" <paksbi at rit.edu>
> Date: 2005/02/22 Tue PM 11:51:37 EST
> To: <WesVanPelt at att.net>, 
> 	<bobcherry at cox.net>, 
> 	<radsafe at radlab.nl>
> Subject: the magnetar eruption
> 
> OK - I dug up some information on the magnetar we've been discussing.  The integrated energy output was about 10^46 ergs and the distance was about 15 kilo-parsecs.  One parsec is about 3.26 light years, or about 3.086x10^18 cm.  
>  
> Quick calculation - the energy flux at the top of the earth's atmosphere from the magnetar flare was about 0.4 ergs per square cm, integrated over the entire event (assuming a total energy of 10^46 ergs).  1 rad is equal to the absorption of 100 ergs per gram of absorber, so this would give a maximum dose of about 4 mrad (40 microGy) to someone above the atmosphere.  So it's not dangerous (even to astronauts), but still pretty impressive from such a great distance.
>  
> Some other comparisons - a really big solar flare has an energy of about 10^36 ergs (about 1000 times that of a normal flare), a supernova has an energy of about 10^50 - 10^51 ergs, and a gamma ray burst is up to 10^54 ergs (if memory serves me correctly).  Incidentally, I once calculated that a gamma ray burst in the Andromeda Galaxy would produce a measureable dose at the Earth.
>  
> Andy
>