Hard X-ray Emission from the M87 AGN Detected with NuSTAR

Abstract

M87 hosts a 3-6 billion solar mass black hole with a remarkable relativistic jet that has been regularly monitored in radio to TeV bands. However, hard X-ray emission \gtrsim 10keV, which would be expected to primarily come from the jet or the accretion flow, had never been detected from its unresolved X-ray core. We report NuSTAR detection up to 40 keV from the the central regions of M87. Together with simultaneous Chandra observations, we have constrained the dominant hard X-ray emission to be from its unresolved X-ray core, presumably in its quiescent state. The core spectrum is well fitted by a power law with photon index Gamma=2.11 (+0.15 -0.11). The measured flux density at 40 keV is consistent with a jet origin, although emission from the advection-dominated accretion flow cannot be completely ruled out. The detected hard X-ray emission is significantly lower than that predicted by synchrotron self-Compton models introduced to explain emission above a GeV.

arXiv comment5 pages, 4 figures, updated to better match the published version in the Astrophysical Journal Letters. A minor typo in the published version (angular scale should be 1 arcsec = 78 pc instead, no result of the paper is affected) is fixed here

References in corpus (22)

• The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections
• Hot Accretion Flows Around Black Holes
• The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances
• The Atlas3D project -- I. A volume-limited sample of 260 nearby early-type galaxies: science goals and selection criteria
• Jet Launching Structure Resolved Near the Supermassive Black Hole in M87
• The supermassive black hole of M87 and the kinematics of its associated gaseous disk
• Fast variability of TeV gamma-rays from the radio galaxy M 87
• The Black Hole Mass, Stellar M/L, and Dark Halo in M87
• NuSTAR Observations of the Bullet Cluster: Constraints on Inverse Compton Emission
• The Inner Jet of the Radio Galaxy M87
• Fermi Large Area Telescope Gamma-Ray Detection of the Radio Galaxy M87
• The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87
• Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
• The central parsecs of M87: jet emission and an elusive accretion disc
• The Outburst of HST-1 in the M87 Jet
• Inside the Bondi radius of M87
• Variability Timescales in the M87 Jet: Signatures of E-Squared Losses, Discovery of a Quasi-period in HST-1, and the Site of TeV Flaring
• Hard X-ray emission from the Galactic ridge
• The Megasecond Chandra XVP Observation of NGC 3115: Witnessing the Flow of Hot Gas within the Bondi Radius
• Spatially Resolving a Starburst Galaxy at Hard X-ray Energies: NuSTAR, Chandra, AND VLBA Observations of NGC 253
• Exploring the accretion model of M87 and 3C 84 with the Faraday rotation measure observations
• An accretion-jet model for M87: interpreting the spectral energy distribution and Faraday rotation measure

Cited by in corpus (9)

• Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
• Hadronic High-energy Emission from Magnetically Arrested Disks in Radio Galaxies
• The 7-year MAXI/GSC X-ray Source Catalog in the High Galactic-Latitude Sky (3MAXI)
• Bremsstrahlung in GRMHD models of accreting black holes
• Black hole spin from wobbling and rotation of the M87 jet and a sign of a magnetically arrested disc
• The possible submillimeter bump and accretion-jet in the central supermassive black hole of NGC 4993
• High-energy Gamma-rays from Magnetically Arrested Disks in Nearby Radio Galaxies
• Universality of coronal properties in accreting black holes across mass and accretion rate
• The Study of X-Ray Flux Variability of M87