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The Project Mapping the Stellar Kinematics of Nearby Galaxies. J. Falc ó n-Barroso Collaborators: M. Balcells, A. Vazdekis, and the SAURON Team. The Team. PIs: R. Bacon ( Lyon ) , R.L. Davies ( Oxford ) , P.T. de Zeeuw ( Leiden ) CoIs:
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The ProjectMapping the Stellar Kinematics of Nearby Galaxies J. Falcón-Barroso Collaborators: M. Balcells, A. Vazdekis, and the SAURON Team
The Team • PIs: R. Bacon (Lyon), R.L. Davies (Oxford), P.T. de Zeeuw (Leiden) • CoIs: M. Bureau, M. Cappellari, E. Emsellem, J. Falcón-Barroso, D. Krajnovic, H. Kuntschner, R. McDermid, R.F. Peletier • Associates: R. van den Bosch, Y. Copin, K. Fathi, K. Ganda, B. Gerken, J. de Jong, E. Jourdeuil, B. Miller, G. Monnet, M. Sarzi, T. Statler, G. van de Ven, A. Weijmans,... • http://www.strw.leidenuniv.nl/sauron
Outline • Integral field kinematic features in early-type galaxies • Central disks, KDCs, Kin. Twists, CRCs • Pseudobulges • High spatial resolution stellar kinematics with OASIS • A detailed study: NGC7332 • A SAURON look at galaxy bulges • Projects on bulges • Minor-axis stellar kinematics (Flat velocity disp. Profiles) • The SAURON Bars Project • Conclusions
Emsellem et al. 2004, MNRAS, in press (astroph/0404034) SAURON Stellar Velocity Fields
NGC4526 NGC4459 Stellar Kin: Central Stellar Disks(Bureau et al. , Emsellem et al.) Central Disks: • I: Disky isophotes • V:Pinched isovelocities Double-hump • : Max along minor axis Min along major-axis • h3:Anti-correlated with V Kin. Twists: (Triaxiality) • V: Kin. twist/misalignment KDCs: • V: Abrupt kin. twist Abrupt V change Peculiarities Strong/weak: (NGC4526, 4459)
NGC4477 NGC4365 Stellar Kin.: Kin. Twists and KDCs Central Disks: • I: Disky isophotes • V: Pinched isovelocities Double-hump • : Max along minor axis Min along major-axis • h3: Anti-correlated with V Kin. Twists: (Triaxiality) • V: Kin. twist/misalignment KDCs: • V: Abrupt kin. twist Abrupt V change Peculiarities Kinematic Twist: (NGC4477) KDC: (NGC4365) Davies et al. 2001
NGC3414 NGC3608 Stellar Kin.: CRs Others: (Crs; NGC3414, 3608)
NGC4473 NGC4550 Stellar Kin.: Others Others: (CR; NGC4473, 4550)
NGC3384 NGC7457 Pseudobulges NGC3384 Flat velocity dispersion along the major axis due to a central disk NGC7457 Flat velocity dispersion field Best candidates for pseudobulges in Pinkney et al. 2003
SAURON and OASIS • SAURON: global kinematics and line-strengths • OASIS spatial resolution: zoom-in on nucleus • Allows study of orbital structure near central BH NGC 4382 McDermid et al. (2004)
Stellar Kin.: Comp. Incidence • Central stellar disks pervasive (70-80%) • KDCs and counterrotation numerous (>20-30%; >15-20%) • Non- axisymmetries very common (45-60%) • Regular axisymmetric objects not as frequent (20-40%)
A Case Study: NGC7332(Falcón-Barroso et al. 2004) • Ordinary looking Boxy-S0 galaxy • Regular stellar kinematics (Fisher et al. 1994) • Plateau in the light profile (Lutticke et al. 2000) • Photometrically detected central disk (Seifert & Scorza 1996) • Complex gas distribution, showing a strong counter-rotating H component and a weak co-rotating one. (Plana & Boulesteix 1996) • Flat H line-strength along major axis (Bender & Paquet 1999) NGC7332 NGC7339
A Case Study: NGC7332 I-band major axis light profile (Peletier & Balcells 1997) SAURON FoV
A Case Study: NGC7332 Major-Axis • Stellar Kinematics • Cylindrical Rotation • Double-hump rotation curve • A Kinematically Decoupled Core • Double-peak velocity dispersion • Kinematic Evidence of the Central Disk
A Case Study: NGC7332 • Ionized Gas Kinematics • Complex gas distribution in general with some signs of ordered motion. • Off-plane gas clumps
A Case Study: NGC7332 • Absorption Line Strength Raw • Age+Metallicity Clean
A Case Study: NGC7332 • Interpretation of the Results: • The presence of a bar • Boxy bulge • Plateau in the light profile • Cylindrical Rotation • Double-hump rotation curve • Velocity dispersion profile with a central minimum and a plateau at moderate radii • Strong h3 – V anti-correlation (revealing the central disk) • Homogeneous stellar populations (being 4-6 Gyr everywhere in the galaxy) • The origin of the gas • A tidal interaction with the neighbour galaxy NGC7339 • Evolutionary Scenarios • The bar has certainly affected the evolution of NGC7332 • It is also quite possible that interactions played a role in the shaping of NGC7332
A look at galaxy bulges • Ongoing projects on bulges • 24 Sa bulges (as part of the main survey) • 11 S0-Sbc bulges from the Balcells & Peletier sample • 22 Sb-Sm bulges (M. Carollo & R.F. Peletier)
The Balcells & Peletier Sample • A sample of highly inclined (i>50º) nearby galaxies to look at pure bulges with no disk contamination. • Photometry of 45 nearby bulges • (Balcells & Peletier 1994) • (Andredakis et al. 1995) • (Peletier & Balcells 1997) • (Balcells et al. 2003, 2004a, 2004b) • Stellar Populations of 19 bulges • (Peletier et al. 1999) • (Falcón-Barroso et al. 2002) • (Falcón-Barroso et al. 2003a) • Kinematics of 19 nearby bulges • (Falcón-Barroso et al. 2003b)
Minor-Axis Stellar Kinematics in bulges(Falcón-Barroso et al 2003b) • Long Slit spectroscopy (minor axis) of 19 bulges from the Balcells & Peletier sample • ISIS at WHT (La Palma) • Ca II triplet region • SSP models from Vazdekis et al. 2003 used as templates for kinematics
Rotation in the inner parts Minor-Axis Stellar Kinematics in bulges • Minor Axis Rotation
Velocity Dispersion Profiles Minor-Axis Stellar Kinematics in bulges • Centrally Peaked Profs. • Classical bulges • Large Vel. Disp. Gradient (s<<0) • Flat Profiles • Bulges dominated by rotation • (Pseudobulges?, Kormendy 1993) • Small Vel. Disp. Gradient (s~0)
Velocity dispersion gradients Minor-Axis Stellar Kinematics in bulges No correlations were found with bulge luminosity, central velocity dispersion or Sérsic index n Barred or box-peanut bulges Non-Barred bulges
The Bar Project(Jourdeuil et al.) • 2 strong barred galaxies observed (Aug 2003) • NGC936 • NGC6951 • Scientific Goals • 2D application of the Tremaine-Weinberg method to measure pattern speeds and quantify uncertainties in 1D data • Detailed study of the orbital structure using N-body simulations • Link between the orbital structure and the stellar populations
Conclusions • Stellar kinematics exhibits rich variety: • (central disks pervasive; KDCs/CRs numerous; non-axisymmetry common) • Number of KDCs/CRs likely to increase with higher spatial resolution (i.e. OASIS) • NGC7332 shows evidence for hosting a bar + signatures for recent interactions (with neighbour galaxy NGC7339?) • Big SAURON effort on spiral bulges (3 complementary samples are being studied) • Long slit minor axis stellar kinematics, on the Balcells & Peletier sample, show a wide range of velocity dispersion profiles • Both, flattened bulges and galaxies with brighter face-on disk central surface brightness showing shallower velocity dispersion profiles • A specific SAURON project on barred galaxies has started with the main goal of studying in detail the orbital distribution its link with stellar populations