Extragalactic Gamma-ray Background from Star-forming Galaxies: Will Empirical Scalings Suffice?

Abstract

Despite the influx of unprecedented-quality data from the Fermi Gamma-Ray Space Telescope that have been collected over nine years of operation, the contribution of normal star-forming galaxies to the extragalactic gamma-ray background (EGRB) remains poorly constrained. Different estimates are discrepant both their underlying physical assumptions and their results. With several detections and many upper limits for the gamma-ray fluxes of nearby starforming galaxies now available, estimates that rely on empirical scalings between gamma-ray and longer-wavelength luminosities have become possible and increasingly popular. In this paper we examine factors that can bias such estimates, including: a) possible sources of nontrivial redshift dependence; b) dependence on the choice of star-formation tracer; c) uncertainties in the slope and normalisation of empirical scalings. We find that such biases can be significant, pointing towards the need for more sophisticated models for the star-forming galaxy contribution to the gamma-ray background, implementing more, and more confident, physics in their buildup. Finally, we show that there are large regions of acceptable parameter space in observational inputs that significantly overproduce the gamma-ray background, implying that the observed level of the background can yield significant constraints on models of the average cosmic gamma-ray emissivity associated with star formation.

arXiv comment13 pages, 7 figures, accepted to MNRAS

References in corpus (47)

• Star Formation in Galaxies Along the Hubble Sequence
• The Global Schmidt Law in Star Forming Galaxies
• Star Formation in the Milky Way and Nearby Galaxies
• On the normalisation of the cosmic star formation history
• The Star Formation Rate and Dense Molecular Gas in Galaxies
• The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV
• The GALEX Ultraviolet Atlas of Nearby Galaxies
• Fermi-LAT Observations of the Diffuse Gamma-Ray Emission: Implications for Cosmic Rays and the Interstellar Medium
• EGRET Observations of the Extragalactic Gamma Ray Emission
• Dust-Corrected Star Formation Rates of Galaxies. II. Combinations of Ultraviolet and Infrared Tracers
• The Evolving Interstellar Medium of Star Forming Galaxies Since z=2 as Probed by Their Infrared Spectral Energy Distributions
• The Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived From First-Year Fermi Large Area Telescope Data
• An H-alpha Imaging Survey of Galaxies in the Local 11 Mpc Volume
• GeV Observations of Star-forming Galaxies with \textit{Fermi} LAT
• A new determination of the extragalactic diffuse gamma-ray background from EGRET data
• An Atlas of Galaxy Spectral Energy Distributions from the Ultraviolet to the Mid-Infrared
• A GALEX Ultraviolet Imaging Survey of Galaxies in the Local Volume
• The Fermi-LAT high-latitude Survey: Source Count Distributions and the Origin of the Extragalactic Diffuse Background
• The Origin of the Extragalactic Gamma-Ray Background and Implications for Dark-Matter Annihilation
• Absorption of High Energy Gamma Rays by Interactions With Starlight Photons in Extragalactic Space at High Redshifts and the High Energy Gamma-Ray Background
• The Gamma-Ray Background from Blazars: A New Look
• On The GeV & TeV Detections of the Starburst Galaxies M82 & NGC 253
• Mid- and Far-infrared Luminosity Functions and Galaxy Evolution from Multiwavelength Spitzer Observations up to z~2.5
• Fermi Large Area Telescope Measurements of the Diffuse Gamma-Ray Emission at Intermediate Galactic Latitudes
• The Starburst Contribution to the Extra-Galactic Gamma-Ray Background
• The Guaranteed Gamma-Ray Background
• On the Kennicutt-Schmidt relation of low-metallicity high-redshift galaxies
• Cosmic Gamma-Ray Background from Star-Forming Galaxies
• Components of the Extragalactic Gamma Ray Background
• First detection of GeV emission from an ultraluminous infrared galaxy: Arp 220 as seen with the Fermi Large Area Telescope
• Diffuse Gamma-Rays from Local Group Galaxies
• The Metallicity Dependence of the Minimum Mass for Core-Collapse Supernovae
• Contribution from Star-Forming Galaxies to the Cosmic Gamma-Ray Background Radiation
• Imprint of galaxy clustering in the cosmic gamma-ray background
• Discovery of GeV emission from the direction of the luminous infrared galaxy NGC 2146
• Are Starburst Galaxies Proton Calorimeters?
• Contribution to the Extragalactic Gamma-ray Background from the Cascades of Very-high Energy Gamma Rays from Blazars
• Star-Forming Galaxies Significantly Contribute to the Isotropic Gamma-Ray Background
• The Impact of Metallicity on the Rate of Type Ia Supernovae
• Are Diffuse High Energy Neutrinos and Gamma-Rays from Starburst Galaxies Observable?
• Luminous infrared galaxies as plausible gamma-ray sources for GLAST and IACTs
• Cosmic rays in galaxies: a probe of star formation
• The Extragalactic Background Light Absorption Feature in the Blazar Component of the Extragalactic Gamma-ray Background
• The Spectral Shape of the Gamma-ray Background from Blazars
• The Star Formation Law in a Multifractal ISM
• The Pionic Contribution to Diffuse Gamma Rays: Upper Limits
• Unresolved Unidentified Source Contribution to the Gamma-ray Background

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• The Heraklion Extragalactic Catalogue (HECATE): a value-added galaxy catalogue for multi-messenger astrophysics
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