1 / 20

Triaxial galaxy models

Triaxial galaxy models. Glenn van de Ven Institute for Advanced Study glenn@ias.edu. Outline. Fast and slow rotators with SAURON Paper IX: Emsellem et al. (2007, MNRAS, 379, 401) Paper X: Cappellari et al. (2007, MNRAS, 379, 418) Triaxial Schwarzschild models

cheri
Download Presentation

Triaxial galaxy models

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Triaxial galaxy models Glenn van de Ven Institute for Advanced Study glenn@ias.edu

  2. Outline • Fast and slow rotators with SAURON • Paper IX: Emsellem et al. (2007, MNRAS, 379, 401) • Paper X: Cappellari et al. (2007, MNRAS, 379, 418) • Triaxial Schwarzschild models • van de Ven, de Zeeuw & van den Bosch (2008, MNRAS, in press) • van den Bosch, van de Ven, et al. (2008, MNRAS, in press) • Next steps and summary Glenn van de Ven, "Triaxial galaxy models"

  3. Integral-field spectroscopy … a spectrum at every position on the plane of the sky Glenn van de Ven, "Triaxial galaxy models"

  4. E E E E E E E E E E E E E E E E E E E E E E E E 40% fast rotators classified as E in RC3 Slow rotators SAURON stellar velocity fields 48 E/S0s Glenn van de Ven, "Triaxial galaxy models"

  5. Kinematical misalignment Fast rotators Slow rotators … simplified spin parameter Glenn van de Ven, "Triaxial galaxy models"

  6. Single component Multiple components Central low velocity KT = Kinematical Twist KM = Kin. Misalignment KDC = Kin. Decoupled Comp. LV = Low Velocity NGC 4382 NGC 5813 Kinematical components Fast rotators Slow rotators Glenn van de Ven, "Triaxial galaxy models"

  7. KDCs: age versus size Slow rotators Fast rotators Paper VIII: McDermid et al. (2007, MNRAS, 373, 906) Glenn van de Ven, "Triaxial galaxy models"

  8. δ = 0 isotropic i = 90° edge-on i = 0° δ = 0.6 Understanding the V/σ-ε diagram Fast rotators Slow rotators • Results consistent with (axisymmetric) modeling subsample • Two classes of early-type galaxies • Oblate anisotropic fast-rotators • (Weakly) triaxial slow-rotators Glenn van de Ven, "Triaxial galaxy models"

  9. Image of numerical orbit Glenn van de Ven, "Triaxial galaxy models"

  10. images of model orbits observed image Schwarzschild’s approach • Surface brightness  (MGE) gravitational potential • Grid of (E,I2,I3)  initial orbit conditions  orbit library • Weighted superposition of orbits that best fits photometry and kinematics  dynamical model Schwarzschild (1979), Richstone & Tremaine (1988), Rix et al. (1997), van der Marel (1998), Cappellari et al. (2002), Gebhardt et al. (2003), … Glenn van de Ven, "Triaxial galaxy models"

  11. z x y 1. Box orbit 2. Inner long- axis tube orbit 3. Outer long- axis tube orbit 4. Short-axis tube orbit Triaxial Schwarzschild models • (MGE) mass model that allows for PA twist in observed SB • (De)projection involves three viewing angles (θ,,) • Four major orbit families: • Robust test with theoretical 3-integral triaxial Abel models Glenn van de Ven, "Triaxial galaxy models"

  12. Application to NGC 4365 V σ h3 h4 Model Symmetrized Data Glenn van de Ven, "Triaxial galaxy models"

  13. Viewing direction and shape Best-fit (θ,,) = (68°,73°,91°) oblate … triaxial T = (1-p2)/(1-q2) Oblate: p=1 (a=b>c), T=0 Prolate: p=q (a>b=c), T=1 Glenn van de Ven, "Triaxial galaxy models"

  14. Orbital structure • Dominant prograde and retrograde short-axis tubes nearly cancel • Retrogade long-axis tubes only ~20% mass, but provide large scale rotation • KDC no distinct separate component; no age gradient Glenn van de Ven, "Triaxial galaxy models"

  15. Metallicity and age in NGC 4365 Davies et al. (2001, ApJ, 548, 33) Glenn van de Ven, "Triaxial galaxy models"

  16. Next steps • Built-up red sequence • Complete sample Atlas3D (265 E/S0, MK≤-21.5, D≤41 Mpc) • Axisymmetric/Triaxial dynamical models of fast/slow rotators • Comparison with (cosmological) simulations • Linking dynamics and stellar populations • Comparison using kinemetry (Kuntschner et al. 2008, in prep.) • Including colors, ages and metallicities in dynamical models • Other modeling applications • Globular clusters (van de Ven et al. 2006, A&A, 445, 513) • Dark halo (Weijmans et al., 2008, MNRAS, 383, 1343) • Spiral galaxies (Ganda, van de Ven & Peletier, 2008, in prep.) • Gravitational lensing and dynamics Glenn van de Ven, "Triaxial galaxy models"

  17. Summary in figures Slow rotators Fast rotators Kinematical misalignment KDCs NGC 4365 Glenn van de Ven, "Triaxial galaxy models"

  18. See also … http://www.strw.leidenuniv.nl/sauron/ http://www-astro.physics.ox.ac.uk/atlas3d/ Glenn van de Ven, "Triaxial galaxy models"

  19. ω Centauri Dynamics of Globular Clusters van de Ven et al. (2006, A&A, 445, 513) Glenn van de Ven, "Triaxial galaxy models"

  20. Ionized and cold gas Weijmans et al. (2008, MNRAS, 383, 1343) Glenn van de Ven, "Triaxial galaxy models"

More Related