ar X iv : a st ro - p h / 97 10 26 4 v 1 2 3 O ct 1 99 7 Kinematics of the Nuclear Ionized Gas in the Radio Galaxy M 84 ( NGC 4374
نویسندگان
چکیده
We present optical long-slit spectroscopy of the nucleus of the nearby radio galaxy M84 (NGC 4374 = 3C 272.1) obtained with the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST). Our spectra reveal that the nuclear gas disk seen in WFPC2 imaging by Bower et al. (1997, ApJ, 483, L33) is rotating rapidly. The velocity curve has an S-shape with a peak amplitude of 400 km s at 0. 1 = 8 pc from the nucleus. To model the observed gas kinematics, we construct a thin Keplerian disk model that fits the data well if the rotation axis of the gas disk is aligned with the radio jet axis. These models indicate that the gas dynamics are driven by a nuclear compact mass of 1.5×10 M⊙ with an uncertainty range of (0.9−2.6)×10 9 M⊙ and that the inclination of the disk with respect to the plane of the sky is 75 − 85. Of this nuclear mass, only ≤ 2 × 10 M⊙ can possibly be attributed to luminous mass. Thus, we conclude that a dark compact mass (most likely a supermassive black hole) resides in the nucleus of M84. Subject headings: galaxies: active — galaxies: elliptical and lenticular, cD — galaxies: individual (M84) — galaxies: kinematics and dynamics — galaxies: nuclei
منابع مشابه
ar X iv : a st ro - p h / 98 10 22 3 v 1 1 4 O ct 1 99 8 Properties of the Neutral ISM in NGC 185 and NGC 205
We describe the properties and kinematics of the neutral gas in the two dwarf elliptical galaxies NGC 185 and NGC 205, companions of M31. The kinematics of the HI suggest that an internal origin of the gas (i.e. stellar mass loss) should be considered, at least in the case of NGC 185. The molecular clouds in these dwarf ellipticals are similar to Galactic giant molecular clouds in many ways. Ho...
متن کاملar X iv : a st ro - p h / 97 05 07 6 v 1 1 2 M ay 1 99 7 Why Does NGC 1068 Have a More Powerful Active Galactic Nucleus than
The nuclear gas kinematics probed by water vapor maser emission has shown that two nearby active galaxies, NGC 1068 and NGC 4258, have a supermassive object in their nuclei and their masses are nearly comparable; a few 10 solar masses. Nevertheless, the activity of the central engine of NGC 1068 is more powerful by two orders of magnitude than that of NGC 4258. Since it is generally considered ...
متن کاملar X iv : a st ro - p h / 99 10 14 1 v 1 7 O ct 1 99 9 X - ray - emitting Atmospheres of B 2 Radio Galaxies
Received ; accepted – 2 – ABSTRACT We report ROSAT PSPC spatial and spectral analysis of the eight B2 radio galaxies 3C 449, expected to be representative of the class of low-power radio galaxies. Multiple X-ray components are present in each, and the gas components have a wide range of linear sizes and follow an extrapolation of the cluster X-ray luminosity/temperature correlation, implying th...
متن کاملar X iv : a st ro - p h / 97 10 18 3 v 1 1 6 O ct 1 99 7 A MODEL OF THE BROAD - BAND CONTINUUM OF NGC 5548
We discuss a model of the central source in Seyfert 1 galaxy NGC 5548. The model assumes a three phase disk structure consisting of a cold outer disk, a hot central disk constituting a Comptonizing X/γ source, and an intermediate unstable and complex phase emitting a soft excess component. The model qualitatively explains broad-band spectrum and variability behavior assuming that the soft exces...
متن کاملar X iv : a st ro - p h / 99 03 37 8 v 1 2 4 M ar 1 99 9 Sub - Relativistic Radio Jets and Parsec - Scale Absorption in Two Seyfert Galaxies
The Very Long Baseline Array has been used at 15 GHz to image the milliarcsecond structure of the Seyfert galaxies Mrk 231 and Mrk 348 at two epochs separated by about 1.7 yr. Both galaxies contain parsec-scale double radio sources whose components have brightness temperatures of 10 9 –10 11 K, implying that they are generated by synchrotron emission. The nuclear components are identified by th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1997