Crete, 1/24 Mapping the kinematics and stellar populations of E/S0s with SAURON Harald Kuntschner Crete, 12 th August 2004

Crete, 2/24 Outline Introduction The SAURON survey Results from –Kinematics –Stellar populations with focus on environmental effects Conclusions

Crete, 3/24 The SAURON team PIs: Bacon, Davies, de Zeeuw COIs: Bureau, Cappellari, Emsellem, Falcón- Barroso, Krajnovi ć, Kuntschner, McDermid, Peletier plus associated members …

Crete, 4/24 Galaxy formation When and how do E/S0/Sa galaxies form? –What is the orbital make-up of E/S0s? –What is the average age and metal content? –Origin of substructures; e.g. faint disks in Es, decoupled cores, etc. –E  S0  Sa transformations? –What is the relationship between global properties and super-massive black holes ? SAURON

Crete, 5/24 The SAURON project Systematic study of a representative sample of 48 nearby E/S0s and 24 Sa-type spirals –Wide field integral-field spectroscopy from the ground (SAURON) –Central high spatial sampling integral-field spectroscopy with OASIS/GMOS –HST imaging (and some STIS spectroscopy) –Large scale ground based imaging de Zeeuw et al, 2002, MNRAS, 329, 513

Crete, 6/24 The sample selection Uniformly covering the ellipticity vs MB plane MB  -18 mag (factor of 50 in luminosity) 24 E, 24 S0, 24 Sa (each 12 cluster, 12 field) cz < 3000 km/s DEC: -6° < d < +64° and |b|  15°

Crete, 7/24 Why integral-field spectroscopy? Galaxy Image Velocity field Velocity curve Integral field Long slit

Crete, 8/24 Status of the SAURON survey Observations completed in April 2002 –8 runs on William Herschel Telescope (4m) –35.5/56 clear nights ~ independent galaxy spectra All data homogeneously reduced Analysis and interpretation ongoing –5 refereed papers in 2004 so far

Crete, 9/24 48 E/S0 – DSS images Emsellem et al., 2004, MNRAS, 352, 721

Crete, 10/24 SAURON-classified rotators S0 E E E E E E E E E E E EE 40% classified by RC3 as ellipticals

Crete, 11/24 SAURON-classified ellipticals E E E E S0 E E E E E E E General agreement with RC3

Crete, 12/24 Results from the kinematic maps Two classes of early-type galaxies –Flattened rotating lenticulars (some with bars) –Triaxial ellipticals (many kinematically decoupled components) Discontinuous transition NGC 4660NGC 4458

Crete, 13/24 Line-strength: Age, Z, [Mg/Fe] Wavelength covers H , Fe5015, [OIII], Mgb & Fe5270 Lick/IDS index definitions (+ SAURON adjustments) Indices + Models can be used to estimate luminosity weighted age, Z and abundance ratios.

Crete, 14/24 Kinematics and line-Strengths I V Mgb Fe NGC 4546 NGC 4570 NGC 4406 NGC 4365 NGC 4660 NGC 4382 NGC 4374 N E

Crete, 15/24 Stellar population models Vazdekis (1999) models at Lick resolution (~8.4 Å FWHM) based on Jones (1999) library [MgFe52]=(Mgb x Fe5270)^0.5 Goal: Estimate the luminosity weighted age, metallicity and abundance ratios.

Crete, 16/24 Central Re/8 measurements Traditional RC3 morphologies Mostly old Es Weak evidence for young stellar populations in some field Es S0s in all environs spread to younger ages

Crete, 17/24 Central Re/8 measurements New “morphologies” based on 2-dim kinematics 7 triaxial Es in field only 4 triaxial Es in cluster

Crete, 18/24 NGC 5198 (E; field) V HβHβ [MgFe50] Age mapZ map

Crete, 19/24 NGC 4150 (S0; cluster) V HβHβ [MgFe50] Age mapZ map

Crete, 20/24 NGC 4570 (S0; cluster) V HβHβ [MgFe50] Age mapZ map

Crete, 21/24 A bar in NGC 4570 van den Bosch & Emsellem (1998) Metal lines Age map

Crete, 22/24 NGC 4382 (S0; cluster) V HβHβ [MgFe50] Age mapZ map

Crete, 23/24 Statistics – young populations 19/48 (40%) of our sample show some evidence of “young” (<10Gyr) stellar populations in the central regions E cluster:1/12 E field:4/12E total:5/24 S0 cluster:7/12 S0 field:7/12S0 total:14/24

Crete, 24/24 Conclusions SAURON provides 2-dim kinematics and line-strength for 48 nearby E/S0 Kinematics –Many RC3 classified Es show strong rotation; we suggest new classification in triaxial Es and rotators Line-strength –Connection between ‘disk-like’ kinematics and enhanced Mgb line-strength (not seen so clearly in Fe lines!) –Evidence for secular, bar-driven evolution in S0s young pops rotation connection in some galaxies –As many as 40% of E/S0 galaxies show signs of young stellar populations mostly in the central regions Only weak evidence for environmental effects in our sample