A Photon densities within galtactic disc compared to CMB

AI Thread Summary
The discussion focuses on the average photon densities in galactic environments, particularly within the galactic disc, compared to the cosmic microwave background (CMB). It highlights the potential for increased photon densities from local sources in denser regions, which may influence cosmic ray phenomenology. Specifically, the conversation explores how these photon densities could affect photo-pion production rates and the attenuation of ultra-high energy cosmic rays, potentially explaining discrepancies in observed flux and composition. The original poster seeks literature or insights on broad spectrum photon intensities in these environments. Overall, the thread emphasizes the need for more research on photon densities in galactic contexts.
UHECRon
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I am interested in what the average photon densities are within galactic environments due to non CMB sources. In extra galactic environments, the CMB certainly dominates, however as you enter more dense and luminous areas (e.g. , the galactic disc) broad spectrum photon densities from local sources must climb. My question is how does this compare on average to CMB?

I ask as the answer may have implications on cosmic ray phenomenology.
 
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UHECRon said:
I ask as the answer may have implications on cosmic ray phenomenology.

In what way?
 
I was wondering about the rates of photo-pion production in the galactic disc as opposed to those more traditionally calculated in extra galactic spaces. The thought being that a significant enhancement of attenuation of Ultra high energy cosmic rays in the regime could help to explain some discrepancies observed in both flux and composition at these extreme energies in the northern and southern hemispheres.

A lazy literature search hasn't turned up much on broad spectrum photon intensities in galactic environments so I was hoping someone would point me in a helpful direction.
 
I see. Well, I doubt I can help you at all. Best of luck on your search!
 
Thanks! Hope I find something. If I do, I will report it here.

If anyone reads this and has any insights, I would be most thankful for some information.
 
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