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

Wong, Ka-Wah and Nemmen, Rodrigo S. and Irwin, Jimmy A. and Lin, Dacheng (2017) Hard X-ray Emission from the M87 AGN Detected with NuSTAR. Astrophysical Journal Letters, 849 (1). Art. No. L17. ISSN 2041-8213. doi:10.3847/2041-8213/aa92c2.

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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.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Wong, Ka-Wah0000-0002-5267-2867
Nemmen, Rodrigo S.0000-0003-3956-0331
Irwin, Jimmy A.0000-0003-4307-8521
Lin, Dacheng0000-0001-5683-5339
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.
Funding AgencyGrant Number
Subject Keywords:accretion, accretion disks – black hole physics – galaxies: elliptical and lenticular, cD – galaxies: individual (M87) – galaxies: nuclei – X-rays: galaxies
Issue or Number:1
Record Number:CaltechAUTHORS:20171017-090307513
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Official Citation:Ka-Wah Wong et al 2017 ApJL 849 L17
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:82404
Deposited By: Joy Painter
Deposited On:17 Oct 2017 18:07
Last Modified:15 Nov 2021 19:50

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