2014/11/30 by Jovana Petrović, Jovana Petrovic, Pasquale D. Serpico +3 · 137 citations
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #Fermi Gamma-ray Space Telescope #Galactic Center #Galaxy #Luminosity #Luminosity function #Milky Way #Millisecond pulsar #Physics #Population #Pulsar #Pulsars and Gravitational Waves Research #Range (aeronautics) #astro-ph.HE #hep-ph
paper · pdf · doi:10.1088/1475-7516/2015/02/023
published in Journal of Cosmology and Astroparticle Physics 2015(02), 023 (Institute of Physics) · 21 pages, 5 tables, 2 figures; modified to match the published version
openalex publication_date 2015/02/18 · arxiv created 2015/02/25 · arxiv updated 2015/06/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Several groups of authors have analyzed Fermi LAT data in a region around the Galactic Center finding an unaccounted gamma-ray excess over diffuse backgrounds in the GeV energy range. It has been argued that it is difficult or even impossible to explain this diffuse emission by the leading astrophysical candidates—millisecond pulsars (MSPs). Here we provide a new estimate of the contribution to the excess by a population of yet unresolved MSP located in the bulge of the Milky Way. We simulate this population with the GALPLOT package by adopting a parametric approach, with the range of free parameters gauged on the MSP characteristics reported by the second pulsar catalogue (2PC). We find that the conclusions strongly depend on the details of the MSP luminosity function (in particular, its high luminosity end) and other explicit or tacit assumptions on the MSP statistical properties, which we discuss. Notably, for the first time we study the importance of the possible secondary emission of the MSPs in the Galactic Center, i.e. the emission via inverse Compton losses of electrons injected in the interstellar medium. Differently from a majority of other authors, we find that within current uncertainties a large if not dominant contribution of MSPs to the excess cannot be excluded. We also show that the sensitivities of future instruments or possibly already of the latest LAT data analysis (Pass 8) provide good perspectives to test this scenario by resolving a significant number of MSPs.