It is currently Tue Nov 30, 2021 10:44 am

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: Fri May 11, 2007 1:05 am 
Offline

Joined: Tue Feb 20, 2007 1:10 am
Posts: 5
Location: Padova
Why can we assume that the gas related component of the galactic diffuse backgroound is locally proportional to the gas column density and we cannot assume that the ICS component is proportional to a sort of photon column density? I guess that there is a physical reason connected with the different emission processes (pion decay and bremmstrahlung and on the other hand ICS) but I cannot understand cleraly which.

Luigi


Top
 Profile  
 
 Post subject: IC and gas emission
PostPosted: Wed May 23, 2007 1:04 am 
Offline

Joined: Wed May 17, 2006 7:02 am
Posts: 285
Location: MPE Garching
From the physical point of view, there is no difference (except that the
ISRF has a spectrum of course, while the gas has not).

the main practical difference is how the gas column density and the ISRF
are derived: the gas is taken directly from HI, CO surveys (as function of position) in galactocentric rings, while the ISRF is computed from a model
at every point.

_________________
Andy Strong, MPE


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 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:  
Powered by phpBB® Forum Software © phpBB Group