THE M87 BLACK HOLE MASS FROM GAS-DYNAMICAL MODELS OF SPACE TELESCOPE IMAGING SPECTROGRAPH OBSERVATIONS

Journal Article · Thu Jun 20 04:00:00 UTC 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/770/2/86· OSTI ID:22127104

Walsh, Jonelle L. ^[1]; Barth, Aaron J. ^[2]; Ho, Luis C. ^[3]; Sarzi, Marc ^[4]

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1. Department of Astronomy, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States)
2. Department of Physics and Astronomy, University of California at Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697-4574 (United States)
3. Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
4. Centre for Astrophysics Research, University of Hertfordshire, AL10 9AB Hatfield (United Kingdom)

The supermassive black hole of M87 is one of the most massive black holes known and has been the subject of several stellar and gas-dynamical mass measurements; however, the most recent revision to the stellar-dynamical black hole mass measurement is a factor of about two larger than the previous gas-dynamical determinations. Here, we apply comprehensive gas-dynamical models that include the propagation of emission-line profiles through the telescope and spectrograph optics to new Space Telescope Imaging Spectrograph observations from the Hubble Space Telescope. Unlike the previous gas-dynamical studies of M87, we map out the complete kinematic structure of the emission-line disk within {approx}40 pc from the nucleus, and find that a small amount of velocity dispersion internal to the gas disk is required to match the observed line widths. We examine a scenario in which the intrinsic velocity dispersion provides dynamical support to the disk, and determine that the inferred black hole mass increases by only 6%. Incorporating this effect into the error budget, we ultimately measure a mass of M{sub BH}= (3.5{sup +0.9}{sub -0.7}) Multiplication-Sign 10{sup 9} M{sub sun} (68% confidence). Our gas-dynamical black hole mass continues to differ from the most recent stellar-dynamical mass by a factor of two, underscoring the need for carrying out more cross-checks between the two main black hole mass measurement methods.

• OSTI ID: 22127104
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 770; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BLACK HOLES
ERRORS
GALAXIES
GALAXY NUCLEI
LINE WIDTHS
MASS
OPTICS
TELESCOPES
VELOCITY