the nucleus of centaurus a
DESCRIPTION
The nucleus of Centaurus A. Nadine Neumayer, Hans-Walter Rix. Almudena Prieto, Klaus Meisenheimer Michele Cappellari Paul van der Werf, Juha Reunanen, Tim de Zeeuw. Ric Davies. Motivation. Nearest elliptical with AGN and jet (1”~17pc) Ideal laboratory to test AGN models - PowerPoint PPT PresentationTRANSCRIPT
4th MPIA Student Workshop – March 26, 2007
The nucleus of Centaurus A
Almudena Prieto, Klaus Meisenheimer
Michele Cappellari
Paul van der Werf, Juha Reunanen, Tim de Zeeuw
Nadine Neumayer, Hans-Walter Rix
Ric Davies
4th MPIA Student Workshop – March 26, 2007
Motivation
◊ Nearest elliptical with AGN and jet (1”~17pc)
◊ Ideal laboratory to test AGN models
◊ Evidence of recent merger (~0.5 Gyr ago)
◊ Binary black hole?
ESO / WFICTIO / Peng et al. 2002
4th MPIA Student Workshop – March 26, 2007
Cen A on the Mbh relations
Tremaine et al. 2002 Häring & Rix 2004Marconi et al. 2001
Mbh - σ Mbh-Mbulge
σ ~138 km/s
•••●
Silge et al. 2005
●
Msph~6.5×1010 M
4th MPIA Student Workshop – March 26, 2007
WFPC2
3.8’ 3.7kpc
Closer lookJ-band
FWHM = 0.10”
7” ~ 115pc
K-band
FWHM = 0.06”
< 1pc!
Core size: <1 pc FWHM
4th MPIA Student Workshop – March 26, 2007
Stellar mass model
K-band
FWHM = 0.06”
NACO + NICMOS + 2MASS
Multi-Gaussian Expansion
stellar potential
4th MPIA Student Workshop – March 26, 2007
λ [μm]
Central kinematics
Marconi et al. 2001
[FeII]
aperture: 86mas x 54mas
4th MPIA Student Workshop – March 26, 2007
Central kinematics
Marconi et al. 2001
4th MPIA Student Workshop – March 26, 2007
The dynamical model
◊ Thin disk model◊ Gas in hydrostatic equilibrium◊ Potential from stars + black hole◊ Three parameters: • BH mass,
• two angles for disk: i, ζ
4th MPIA Student Workshop – March 26, 2007
Best-fitting model
Hot disk model Mbh = (6.1± 0.8) x 107 M
i = 45°ζ = -27°
Häring-Neumayer et al. 2006
4th MPIA Student Workshop – March 26, 2007
IFU data – SINFONI/VLT
K-band
H-band
4th MPIA Student Workshop – March 26, 2007
[FeII] λ=1.644μm
4th MPIA Student Workshop – March 26, 2007
[SiVI] λ=1.964μm
4th MPIA Student Workshop – March 26, 2007
Brγ λ=2.166μm
4th MPIA Student Workshop – March 26, 2007
H2 λ=2.121μm
4th MPIA Student Workshop – March 26, 2007
Disk parameters - Kinemetry
Using kinemetry routine by Krajnović et al. 2006
4th MPIA Student Workshop – March 26, 2007
Warped disk structure
4th MPIA Student Workshop – March 26, 2007
The dynamical model
◊ Tilted ring model◊ Gas in hydrostatic equilibrium◊ Potential from stars + black hole◊ Two parameters: • BH mass
• disk inclination angle
4th MPIA Student Workshop – March 26, 2007
IFU data and model
Mbh= (7.0±1.5) × 107 M
<i> = 27º±5º
4th MPIA Student Workshop – March 26, 2007
Symmetrised data & model
4th MPIA Student Workshop – March 26, 2007
No black hole?
ruled out by over 5σ!
4th MPIA Student Workshop – March 26, 2007
Cen A on the Mbh relations
Tremaine et al. 2002 Häring & Rix 2004Marconi et al. 2001
Mbh - σ Mbh-Mbulge
σ ~138 km/s
•
Msph~6.5×1010 M
••
Silge et al. 2005
●●
●●
4th MPIA Student Workshop – March 26, 2007
Stellar vs. gas motion
4th MPIA Student Workshop – March 26, 2007
Summary
◊ high resolution gas and stellar kinematics
◊ counter-rotation◊ thin, warped disk model
◊ Mbh = 7 x 107 Msun
◊ In agreement with M-σ