Breaking the Radio - Gamma-Ray Connection in Arp 220
arXiv:1901.04564 · doi:10.1093/mnras/stz223
Abstract
Recent analyses of the gamma-ray spectrum from the ultra-luminous infrared galaxy Arp 220 have revealed a discrepancy in the cosmic ray energy injection rates derived from the gamma-rays versus the radio emission. While the observed radio emission is consistent with the star formation rate inferred from infrared observations, a significantly higher cosmic ray population is necessary to accurately model the measured gamma-ray flux. To resolve this discrepancy between the radio and gamma-ray observations, we find that we must increase the cosmic ray energy injection rate and account for an infrared optical depth greater than unity. Raising the energy injection rate naturally raises the total gamma-ray flux but also raises the radio flux unless there is also an increase in the energy loss rate for cosmic ray leptons. A optically thick medium results in an increase in energy losses via inverse Compton for cosmic ray leptons and preserves agreement with submillimeter, millimeter, and infrared wavelength observations.
arXiv comment17 pages, 11 figures, 4 tables, submitted to MNRAS
References in corpus (48)
- The CO-to-H2 Conversion Factor
- Rotating Nuclear Rings and Extreme Starbursts in Ultraluminous Galaxies
- The IRAS Revised Bright Galaxy Sample (RBGS)
- Radio Properties of Infrared Selected Galaxies in the IRAS 2 Jy Sample
- Energy spectra of gamma-rays, electrons and neutrinos produced at proton-proton interactions in the very high energy regime
- Monte-Carlo simulations of photohadronic processes in astrophysics
- GeV Observations of Star-forming Galaxies with \textit{Fermi} LAT
- Far-infrared Spectral Energy Distribution Fitting for Galaxies Near and Far
- Observations of Arp 220 using Herschel-SPIRE: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment
- The Physics of the FIR-Radio Correlation: I. Calorimetry, Conspiracy, and Implications
- Magnetic Fields in Starburst Galaxies and The Origin of the FIR-Radio Correlation
- Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi
- On The GeV & TeV Detections of the Starburst Galaxies M82 & NGC 253
- The Starburst Contribution to the Extra-Galactic Gamma-Ray Background
- Simplified models for photohadronic interactions in cosmic accelerators
- Radiative Processes in High Energy Astrophysics
- Fermi Large Area Telescope observations of Local Group galaxies: Detection of M31 and search for M33
- Theoretical modelling of the diffuse emission of gamma-rays from extreme regions of star formation: The case of Arp 220
- ALMA Resolves the Nuclear Disks of Arp 220
- The far-infrared spectrum of Arp 220
- Winds, Clumps, and Interacting Cosmic Rays in M82
- High-Resolution Radio Continuum Measurements of the Nuclear Disks of Arp 220
- Deep view of the Large Magellanic Cloud with 6 years of Fermi-LAT observations
- First detection of GeV emission from an ultraluminous infrared galaxy: Arp 220 as seen with the Fermi Large Area Telescope
- Seyfert 2 galaxies in the GeV band: jets and starburst
- Klein-Nishina steps in the energy spectrum of galactic cosmic ray electrons
- Extreme dust disks in Arp 220 as revealed by ALMA
- Simulating Gamma-ray Emission in Star-forming Galaxies
- Subarcsecond international LOFAR radio images of Arp 220 at 150 MHz: A kpc-scale star forming disk surrounding nuclei with shocked outflows
- Diffuse Hard X-ray Emission in Starburst Galaxies as Synchrotron from Very High Energy Electrons
- Discovery of GeV Emission from the Circinus galaxy with the Fermi-LAT
- Evaluating the Calorimeter Model with Broadband, Continuous Spectra of Starburst Galaxies Observed with the Allen Telescope Array
- Discovery of GeV emission from the direction of the luminous infrared galaxy NGC 2146
- Equipartition and Cosmic Ray Energy Densities in Central Molecular Zones of Starbursts
- Constraining Gamma-Ray Emission from Luminous Infrared Galaxies with Fermi-LAT; Tentative Detection of Arp 220
- Resolved Structure of Arp 220 Nuclei at λ~3 mm
- The Radio-Gamma Correlation In Starburst Galaxies
- Search for gamma-ray emission from star-forming galaxies with Fermi LAT
- Gamma-Ray Emission from Arp 220: Indications of an Active Galactic Nucleus
- Cosmic Rays, Gamma-Rays, and Neutrinos in the Starburst Nuclei of Arp 220
- High Resolution IRAS Maps and IR Emission of M31 --- I. Morphology and Sources
- The Cosmic Ray Population of the Galactic Central Molecular Zone
- VLA H53alpha radio recombination line observations of the ultraluminous infrared galaxy Arp 220
- Evidence for Cosmic-Ray Escape in the Small Magellanic Cloud using Fermi Gamma-rays
- Gamma-ray activity of Seyfert galaxies and constraints on hot accretion flows
- Interstellar gamma-ray emission from cosmic rays in star-forming galaxies
- Parsec-scale magnetic fields in Arp 220
- A possible GeV-radio correlation for starburst galaxies
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- Evidence of AGN activity in the gamma-ray emission from two starburst galaxies
- High-energy Neutrinos from the Inner Circumnuclear Region of NGC 1068
- IceCube Neutrinos from Hadronically Powered Gamma-Ray Galaxies
- Cosmic Rays and Magnetic Fields in the Core and Halo of the Starburst M82: Implications for Galactic Wind Physics
- No evidence of AGN features in the nuclei of Arp 220 from JWST/NIRSpec IFS
- Gamma-ray emission from spectrally resolved cosmic rays in galaxies
- JWST/NIRSpec insights into the circumnuclear region of Arp 220: A detailed kinematic study
- CONGRuENTS (COsmic-ray, Neutrino, Gamma-ray and Radio Non-Thermal Spectra). I. A predictive model for galactic non-thermal emission