Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 1, 2017 | Submitted
Journal Article Open

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 ≳10 keV, 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 Γ = 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.

Additional Information

© 2017 The American Astronomical Society. Received 2017 September 16; revised 2017 October 5; accepted 2017 October 11; published 2017 October 26. We thank the referee for helpful comments. This work was supported by NASA Chandra grant GO7-18085X and NASA NuSTAR grant NNX17GF12P.

Attached Files

Submitted - 1710.05031.pdf

Files

1710.05031.pdf
Files (772.4 kB)
Name Size Download all
md5:1a25d1b1616d47a4dd5dc6f70ecc3214
772.4 kB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 17, 2023