Open AccessThe central kinematics of NGC 1399 measured with 14 pc resolution
Author(s) -
Houghton R. C. W.,
Magorrian J.,
Sarzi M.,
Thatte N.,
Davies R. L.,
Krajnović D.
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.09713.x
Subject(s) - physics , astrophysics , astronomy , kinematics , observatory , telescope , adaptive optics , very large telescope , line of sight , galaxy , classical mechanics
We present near‐infrared (NIR) adaptive optics‐assisted spectroscopic observations of the CO (Δμ= 2) absorption bands towards the centre of the giant elliptical galaxy NGC 1399. The observations were made with NAOS‐CONICA (on the European Southern Observatory's Very Large Telescope) and have a full width at half‐maximum resolution of 0.15 arcsec (14 pc). Kinematic analysis of the observations reveals a decoupled core and strongly non‐Gaussian line‐of‐sight velocity profiles in the central 0.2 arcsec (19 pc). NIR imaging also indicates an asymmetric elongation of the central isophotes in the same region. We use spherical orbit‐superposition models to interpret the kinematics, using a set of orthogonal ‘eigen‐velocity profiles’ that allow us to fit models directly to spectra. The models require a central black hole of mass 1.2 +0.5 −0.6 × 10 9 M ⊙ , with a strongly tangentially biased orbit distribution in the inner 40 pc.