It is currently Wed Dec 04, 2024 8:20 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 3 posts ] 
Author Message
PostPosted: Mon Aug 30, 2010 9:18 am 
Offline

Joined: Tue Aug 24, 2010 5:46 pm
Posts: 11
Hello,

the output from my GALPROP run
http://galprop.stanford.edu/wrxiv/0353/ ... uo2.tar.gz
contains the following gamma-ray maps for Bremsstrahlung emission:
bremss_ionized_mapcube_54_03530002.gz
bremss_mapcube_54_03530002.gz

Judging from the manual, the bremss_ionized component is the Bremsstrahlung emission produced by interactions with ionized gas, whereas bremss is the total Bremsstrahlung emission, i.e. from interactions with molecular, atomic and ionized gas?

This can't be right, because the 1e4 energy slices have the following mean values in cm^-2 s^-1 sr^-1 MeV^-1:
bremss_ionized ~ 1.6e-5
bremss ~ 3.5e-12

Why is the bremss_ionized component so large and why is it larger than bremss?
Can someone enlighten me?

Christoph

PS: I just noticed that the GALPROP manual (http://galprop.stanford.edu/download/ma ... nual54.pdf, Section 3.4) mentions that the sky maps have units MeV^2 cm^-2 sr^-1 s^-1 MeV^-1. But I think they are not multiplied by E^2, i.e. have units cm^-2 sr^-1 s^-1 MeV^-1.

Is that correct or did I mix things up?


Top
 Profile  
 
PostPosted: Tue Aug 31, 2010 4:38 pm 
Offline

Joined: Wed May 17, 2006 2:35 pm
Posts: 23
Location: Santa Cruz, California
Hi Christoph,

Some components are multiplied by E^2 and others are not. If I recall, the components are multiplied by E^2, while the total ones are plain differential intensities. There is no good reason for this.

_________________
Dr. Troy A. Porter
Hansen Experimental Physics Laboratory
452 Lomita Mall
Stanford University
Stanford, CA 94305


Top
 Profile  
 
PostPosted: Wed Sep 01, 2010 1:10 am 
Offline

Joined: Tue Aug 24, 2010 5:46 pm
Posts: 11
Is making all output maps consistent (either multiplied by E^2 or not) an option?
Or would that cause too much confusion with existing users?

Maybe you could update the GALPROP manual to state which maps were multiplied by E^2 and which were not to avoid confusion. New users like me don't even know the order of magnitude to expect, especially at high energies (say 1 to 100 TeV) where there are very few publications to compare with.

Just to be clear about the magnitude of the bremss_ionized component at 1e4 MeV:
bremss_ionized ~ 1.6e-5 MeV cm^-2 s^-1 sr^-1
bremss_ionized ~ 1.6e-13 cm^-2 s^-1 sr^-1 MeV^-1
Is that right?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group