This has an interesting exploration of the prospects for GLAST. It raised a few questions for me.
I suppose Fig 2 refers to a GLAST-resolution solid angle - as the text seems to indicate, but not mentioned in the caption ?
The EGRET data they quote presumably refer to the point source, so it is not obvious to me what the comparison means since the background involves extended emission. What does it mean to normalize the (galprop) prediction to the EGRET point source ? - the diffuse emission will be higher.
They seem to consider only pion-decay for their background prediction while it is known that inverse Compton is very important (e.g. ApJ 613, 962; 648,L29) especially in the high interstellar radiation fields near the GC. Reference 15 did not help me to understand this: if galprop is used, then it is easy to include inverse Compton.
Apart from this, it would be interesting to know whether tests like that in J. Cosmol Part Phys 5:6 (astro-ph/0602632) are of relevance for the models addressed here ?
[0707.0622] On prospects for dark matter indirect detection in the Constrained MSSM
Authors: | Leszek Roszkowski (Sheffield), Roberto Ruiz de Austri (Autonoma Madrid), Joe Silk (Oxford), Roberto Trotta (Oxford) |
Abstract: | In the framework of the Constrained MSSM we derive the most probable ranges of the diffuse gamma radiation flux from the direction of the Galactic center and of the positron flux from the Galactic halo due to neutralino dark matter annihilation. We find that, for a given halo model, the 95% probability range of the integrated gamma-ray flux spans less than two orders of magnitude, with its detectability by GLAST depending primarily on the cuspiness of the halo profile. The positron flux, on the other hand, appears to be too small to be detectable by PAMELA, unless the boost factor is at least of order ten and/or the halo profile is extremely cuspy. |
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[0707.0622] On prospects for dark matter indirect detection
Hi Andy,
thanks for your interesting comments - perhaps I can clarify a couple of issues here:
We'll look into the issue you mention re the background. However since we are not including constraints coming from EGRET data, our treatment of the background does not impact on the statistical conclusions arrived at in our analysis.
thanks for your interesting comments - perhaps I can clarify a couple of issues here:
Yes, that's right, we ought to mention this in the caption.I suppose Fig 2 refers to a GLAST-resolution solid angle
I think the way it is stated in the text it's acutally a bit misleading, now that I re-read it. We do include inverse Compton, what we meant is that pion-decay is usually the dominant component. We'll make sure this is spellt out more clearly in a revised version.They seem to consider only pion-decay for their background prediction
We'll look into the issue you mention re the background. However since we are not including constraints coming from EGRET data, our treatment of the background does not impact on the statistical conclusions arrived at in our analysis.
Yes, In principle one could imagine performing this kind of test in the global parameter space singled out by our chains. Actually, our MCMC method provides a statistically rigorous framework to carry out this kind of analysis over the whole parameter space, rather then just for a few hand-picked models. Our code is now public (see superbayes.org), so there is certainly scope for this kind of work.Apart from this, it would be interesting to know whether tests like that in J. Cosmol Part Phys 5:6 (astro-ph/0602632) are of relevance for the models addressed here ?
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[0707.0622]
Hi Roberto,
thanks for your clarifications.
My main concern was indeed that you seem to be using the EGRET GC point source spectrum as a reference, although this is probably not relevant to the diffuse emission. Better instead to use actual EGRET diffuse data in this direction, which you can find e.g. in ApJ 613, 962 (astro-ph/0406254).
thanks for your clarifications.
My main concern was indeed that you seem to be using the EGRET GC point source spectrum as a reference, although this is probably not relevant to the diffuse emission. Better instead to use actual EGRET diffuse data in this direction, which you can find e.g. in ApJ 613, 962 (astro-ph/0406254).