The MASSIVE Survey XIII — Spatially Resolved Stellar Kinematics in the Central 1 kpc of 20 Massive Elliptical Galaxies with the GMOS-North Integral-Field Spectrograph. (arXiv:1904.08929v1 [astro-ph.GA])

The MASSIVE Survey XIII — Spatially Resolved Stellar Kinematics in the Central 1 kpc of 20 Massive Elliptical Galaxies with the GMOS-North Integral-Field Spectrograph. (arXiv:1904.08929v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Ene_I/0/1/0/all/0/1">Irina Ene</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ma_C/0/1/0/all/0/1">Chung-Pei Ma</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+McConnell_N/0/1/0/all/0/1">Nicholas J. McConnell</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Walsh_J/0/1/0/all/0/1">Jonelle L. Walsh</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kempski_P/0/1/0/all/0/1">Philipp Kempski</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Greene_J/0/1/0/all/0/1">Jenny E. Greene</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Thomas_J/0/1/0/all/0/1">Jens Thomas</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Blakeslee_J/0/1/0/all/0/1">John P. Blakeslee</a>

We use observations from the GEMINI-N/GMOS integral-field spectrograph (IFS)
to obtain spatially resolved stellar kinematics of the central $sim 1$ kpc of
20 early-type galaxies (ETGs) with stellar masses greater than $10^{11.7}
M_odot$ in the MASSIVE survey. Together with observations from the wide-field
Mitchell IFS at McDonald Observatory in our earlier work, we obtain
unprecedentedly detailed kinematic maps of local massive ETGs, covering a scale
of $sim 0.1-30$ kpc. The high ($sim 120$) signal-to-noise of the GMOS spectra
enable us to obtain two-dimensional maps of the line-of-sight velocity,
velocity dispersion $sigma$, as well as the skewness $h_3$ and kurtosis $h_4$
of the stellar velocity distributions. All but one galaxy in the sample have
$sigma(R)$ profiles that increase towards the center, whereas the slope of
$sigma(R)$ at one effective radius ($R_e$) can be of either sign. The $h_4$ is
generally positive, with 14 of the 20 galaxies having positive $h_4$ within the
GMOS aperture and 18 having positive $h_4$ within $1 R_e$. The positive $h_4$
and rising $sigma(R)$ towards small radii are indicative of a central black
hole and velocity anisotropy. We demonstrate the constraining power of the data
on the mass distributions in ETGs by applying Jeans anisotropic modeling (JAM)
to NGC~1453, the most regular fast rotator in the sample. Despite the
limitations of JAM, we obtain a clear $chi^2$ minimum in black hole mass,
stellar mass-to-light ratio, velocity anisotropy parameters, and the circular
velocity of the dark matter halo.

We use observations from the GEMINI-N/GMOS integral-field spectrograph (IFS)
to obtain spatially resolved stellar kinematics of the central $sim 1$ kpc of
20 early-type galaxies (ETGs) with stellar masses greater than $10^{11.7}
M_odot$ in the MASSIVE survey. Together with observations from the wide-field
Mitchell IFS at McDonald Observatory in our earlier work, we obtain
unprecedentedly detailed kinematic maps of local massive ETGs, covering a scale
of $sim 0.1-30$ kpc. The high ($sim 120$) signal-to-noise of the GMOS spectra
enable us to obtain two-dimensional maps of the line-of-sight velocity,
velocity dispersion $sigma$, as well as the skewness $h_3$ and kurtosis $h_4$
of the stellar velocity distributions. All but one galaxy in the sample have
$sigma(R)$ profiles that increase towards the center, whereas the slope of
$sigma(R)$ at one effective radius ($R_e$) can be of either sign. The $h_4$ is
generally positive, with 14 of the 20 galaxies having positive $h_4$ within the
GMOS aperture and 18 having positive $h_4$ within $1 R_e$. The positive $h_4$
and rising $sigma(R)$ towards small radii are indicative of a central black
hole and velocity anisotropy. We demonstrate the constraining power of the data
on the mass distributions in ETGs by applying Jeans anisotropic modeling (JAM)
to NGC~1453, the most regular fast rotator in the sample. Despite the
limitations of JAM, we obtain a clear $chi^2$ minimum in black hole mass,
stellar mass-to-light ratio, velocity anisotropy parameters, and the circular
velocity of the dark matter halo.

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