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Dimitri Gadotti (Max Planck Institute for Astrophysics – Garching)

MAGPOP Network Meeting What can we learn from imaging and spectroscopy of well-resolved galaxies?. 1. The BUDDA code: - from bulge/disk decomposition to multi-component decomposition 2. Dating secular evolution: - the ages of bars 3. On bars and haloes:

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Dimitri Gadotti (Max Planck Institute for Astrophysics – Garching)

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  1. MAGPOP Network Meeting What can we learn from imaging and spectroscopy of well-resolved galaxies? 1. The BUDDA code: - from bulge/disk decomposition to multi-component decomposition 2. Dating secular evolution: - the ages of bars 3. On bars and haloes: - inferring halo properties from bar properties Dimitri Gadotti (Max Planck Institute for Astrophysics – Garching)

  2. The BUDDA Code (de Souza, Gadotti & dos Anjos 2004) • BUlge/Disk Decomposition Analysis (http://www.mpa-garching.mpg.de/~dimitri/budda.html) • 2D (Image Fitting) • reliable results (de Jong 1995) for galaxies with different components (constraints from PA and ellipticity) • discrepancies among 1D fits can be as large as 100% (Baggett, Baggett & Anderson 1998) • Bulge (Sérsic 1968) • Disk (Freeman 1970) • Residual Images • (sub-structures) Dimitri Gadotti (MPA – Garching)

  3. A Structural Analysis of 51 Early-Type Galaxies • R-band images • Structural parameters • Inner disks in ~ 1/3 of Es • merger signature (see Burstein et al. 2001)? NGC 1052 (E4 – Sey2) residual image direct image Dimitri Gadotti (MPA – Garching)

  4. A Structural Analysis of 51 Early-Type Galaxies IC 1459 • Classified as E3 (RC3) but has a disk! It’s an S0! Also a LINER… • Wrong morphological classification in ~ 1/3 of Es and S0s direct image residual image Dimitri Gadotti (MPA – Garching)

  5. Residual Images and Sub-Structures NGC 4314 (B band – Steward Obs.) (Gadotti & de Souza 2006) NGC 1291 NGC 5850 (Ks – Kitt Peak) (Gadotti & de Souza 2005, 2006) NGC 2217 Dimitri Gadotti (MPA – Garching)

  6. Residual Images and Sub-Structures Dimitri Gadotti (MPA – Garching)

  7. The New BUDDA: Generalized Ellipses • Boxy Es emit strongly in radio/X-ray, are more luminous & massive, and show slow rotation compared to disky Es (e.g., Bender et al. 1989) • Different formation histories (Naab & Burkert 2003)? (e.g., Athanassoula et al. 1990) Pure Boxy Disky Dimitri Gadotti (MPA – Garching)

  8. The New BUDDA: Edge-on Disks van der Kruit & Searle (1981) Dimitri Gadotti (MPA – Garching)

  9. The New BUDDA: Double Exponential Disks • Truncation (Freeman 1970 type II - e.g., Pohlen 2002) • Anti-truncation (Erwin, Beckman & Pohlen 2005) ? 3-5 h0 3-5 h0 Origin: bars, spirals, interactions…??? Dimitri Gadotti (MPA – Garching)

  10. The New BUDDA: Four Components • Central Source • Moffat (1969) profile: fits better seeing effects (see Trujillo et al. 2001a,b) • Bar • Sérsic profile • n=1: late-type bars • n=0.5-1: early-type bars Dimitri Gadotti (MPA – Garching)

  11. The New BUDDA: Four Components AGN Bulge Bar Disk Dimitri Gadotti (MPA – Garching)

  12. Bars and Secular Evolution Bars are to a large extent shaping the physical properties of galaxies (see Kormendy & Kennicutt 2004): - creating rings & spirals arms - attenuating metallicity & color gradients - fueling AGN & central star formation - building bulges Dimitri Gadotti (MPA – Garching)

  13. Questions • When did the first bars appear? • How fast bars drive gas to the center? • For how long a bar modifies the evolution of its host galaxy? • What is the fraction of pseudo-bulge stars? • Are bars really recurrent? Dimitri Gadotti (MPA – Garching)

  14. Estimating the Ages of Bars (see Gadotti & de Souza 2005) y σz x - Thin bars ↔recently-formed; thick bars ↔ evolved - Measure the stellar vertical velocity dispersion Dimitri Gadotti (MPA – Garching)

  15. Spectroscopy • - 14 face-on barred galaxies: Kitt Peak (2.3m) & La Silla (1.5m) • Diversified sample: morphology, AGN and environment Dimitri Gadotti (MPA – Garching)

  16. NGC 4579 Espectros NGC 4394 NGC 5850 NGC 4608

  17. Determining the LOSVDs Gauss-Hermite series (van der Marel & Franx 93) K0III stars Dimitri Gadotti (MPA – Garching)

  18. Radial Profiles of σz σz Young bar r σz Old bar r Central drop in σz (inner disk?) Dimitri Gadotti (MPA – Garching)

  19. Clear Cases Dimitri Gadotti (MPA – Garching)

  20. Let’s Quantify • σZ,bar: at 50%-60% of bar semi-major length • σZ: difference to σZ in the disk at same distance • Young bars: σZ,bar ~ 30 Km/s and σZ ~ 5 Km/s • Old bars: σZ,bar ~ 100 Km/s and σZ ~ 40 Km/s • Statistical tests indicate different populations at the 98% confidence level Dimitri Gadotti (MPA – Garching)

  21. Some Results • AGN activity seems to be found preferentially in young bars (timescale for AGN fueling is short): • 2/8 (25%) of old bars have AGN, but 3/5 (60%) of young bars show activity • Better bar x AGN correlation with young bars! • Bar recurrence may be more frequent in late-type galaxies: • 7/8 (88%) of old bars are early-type, but only 2/5 (40%) of young bars are early-type Dimitri Gadotti (MPA – Garching)

  22. On Bars and Haloes • Previous studies concluded that haloes are against bars (Ostriker & Peebles 1973) • Using live haloes the truth is the opposite (Athanassoula & Misiriotis 2002; see also Athanassoula 2003)! • Angular momentum transfer between halo and disk makes stronger bars • Depends on halo properties like mass and velocity distribution MH | MD Dimitri Gadotti (MPA – Garching)

  23. On Bars and Haloes • Compare the properties of N-body models and real barred galaxies J and Ks near-infrared observations at the Cananea 2.1-m telescope MH | MD N-body simulations Dimitri Gadotti (MPA – Garching)

  24. On Bars and Haloes MH | MD N-body simulations Dimitri Gadotti (MPA – Garching)

  25. On Bars and Haloes MH | MD Real galaxies Dimitri Gadotti (MPA – Garching)

  26. On Bars and Haloes Real galaxies N-body simulations Dimitri Gadotti (MPA – Garching)

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