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Dark matter and pulsar model constraints from Galactic center Fermi/LAT γ-ray observations

Published online by Cambridge University Press:  22 May 2014

Chris Gordon  and
Oscar Macias
Chris Gordon
Affiliation:
Department of Physics and Astronomy, Rutherford Building, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
Oscar Macias
Affiliation:
Department of Physics and Astronomy, Rutherford Building, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
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Abstract

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Employing Fermi/LAT γ-ray observations, several independent groups have found excess extended γ-ray emission at the Galactic center (GC). Both, annihilating dark matter (DM) or a population of ~ 103 unresolved millisecond pulsars (MSPs) are regarded as well motivated possible explanations. However, there is significant uncertainties in the diffuse Galactic background at the GC. We have performed a revaluation of these two models for the extended γ-ray source at the GC by accounting for the systematic uncertainties of the Galactic diffuse emission model. We also marginalize over point source and diffuse background parameters in the region of interest. We show that the excess emission is significantly more extended than a point source. We find that the DM (or pulsar population) signal is larger than the systematic errors and therefore proceed to determine the sectors of parameter space that provide an acceptable fit to the data. We found that a population of several thousand MSPs with parameters consistent with the average spectral shape of Fermi/LAT measured MSPs was able to fit the GC excess emission. For DM, we found that a pure τ+τ− annihilation channel is not a good fit to the data. But a mixture of τ+τ− and bb with a 〈σ v〉 of order the thermal relic value and a DM mass of around 20 to 60 GeV provides an adequate fit.

Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 9 , Symposium S303: The Galactic Center: Feeding and Feedback in a Normal Galactic Nucleus , October 2013 , pp. 414 - 418
Copyright
Copyright © International Astronomical Union 2014 

References

Baltz, E. A., et al.JCAP 0807:013, 2008.CrossRefGoogle Scholar
Bertone, G. & Hooper, D., Silk, J.. Phys. Rep. 405:279–390, January 2005.CrossRefGoogle Scholar
Boyarsky, Alexey, Malyshev, Denys, & Ruchayskiy, Oleg. Phys. Lett. B705:165–169, 2011.CrossRefGoogle Scholar
Cirelli, Marco. eprint 2012.Google Scholar
Goodenough, Lisa & Hooper, Dan. 2009.Google Scholar
Hooper, D. & Goodenough, L.. Phys. Lett. B697:412–428, 2011.Google Scholar
Hooper, D. & Linden, T.. Phys. Rev. D84:123005, 2011.Google Scholar
Hooper, Dan, Cholis, Ilias, Linden, Tim, Siegal-Gaskins, Jennifer, & Slatyer, Tracy. eprint 2013.Google Scholar
Abazajian, Kevork N.. JCAP 1103:010, 2011.Google Scholar
Abazajian, Kevork N. & Kaplinghat, Manoj. Phys. Rev. D86:083511, 2012.Google Scholar
Abazajian, Kevork N. & Kaplinghat, Manoj. Phys. Rev. D 87:129902, Jun 2013.Google Scholar
Linden, Tim, Lovegrove, Elizabeth, & Profumo, Stefano. ApJ 753:41, 2012.CrossRefGoogle Scholar
Nolan, P. L.et al.ApJS 199:31, 2012.Google Scholar
Vitale, Vincenzo & Morselli, Aldo. eprint 2009.Google Scholar
Vitale, V., Morselli, A., & Fermi/LAT Collaboration. Nuclear Instruments and Methods in Physics Research A, 630:147–150, February 2011.CrossRefGoogle Scholar
Gordon, C. & Macias, O., Phys. Rev. D 88, 083521 (2013).Google Scholar
Yusef-Zadeh, F., et al.ApJ 762:33, 2013.Google Scholar