A Spitzer Survey of the Large Magellanic Cloud: Surveying the Agents of a Galaxy’s Evolution (SAGE) Bob Blum (NOAO/Tucson) and the SAGE Team Image credit, Karl Gordon

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 2 SAGE team members: Space Telescope Science Institute: Meixner (PI, database lead), Leitherer (team web page), Nota, Panagia, Vijh University of Wisconsin: Churchwell (IRAC pipeline lead), Meade, Babler, Bracker, Gallagher SSI: Whitney (star formation co-lead) University of Arizona: Gordon (MIPS pipeline lead), Engelbracht, Misselt, For, Zaritsky, Harris, Kelly, Perez Spitzer Science Center/JPL: Reach (ISM co-lead), Latter, van Dyk, Werner, Gorjian NOAO: Blum (Evolved star lead), Olsen, Mould, Points Nagoya University, Japan: Onishi, Fukui, Kawamura, Mizuno, Mizuno (CO survey), Shibai (ASTRO-F), Shuji (Near-IR survey) CESR/Saclay/IAS: Bernard (ISM co- lead), Madden, Boulanger, Paladini UC Berkeley: Cohen (calibration) University of Virginia: Indebetouw (star formation co-lead) Harvard/CfA: Hora (IRAC team) NASA/Ames: Tielens (IRS) Gemini: Volk University of Michigan: Oey University College London: Smith AURA: Frogel CSIRO: Staveley-Smith JHU: Srinivasan University of Denver: Ueta Manchester: Markwick-Kemper (IRS)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 3 Preliminaries 1 parsec (pc) = 3.25 light yr = 3.1x10 18 cm CMD = color-magnitude diagram (temperature vs luminosity for stars- >temperature vs mass) Color = ratio of flux in two broad pass bands (filters)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 4 Lambda CDM & Galaxy Formation =~ 70% DM =~ 25% b =~ 5% + DM + b =1

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 5 Galaxy Formation via Merging Look Back Time (Gyr) Color (B - V) Run simulation, compare to galaxy counts (e.g. SDSS)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 6 The Local Group Resolved stellar populations

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 7 Mergers in the Local Group Milky Way streams, O Cen, Sgr Dwarf Andromeda halo inhomogeneities Problem for LCDM? Deficit of dwarf galaxies

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 8 Magellanic Clouds

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 9 The Large Magellanic Cloud galaxy evolution – Star formation history (SFH) – Chemical enrichment history (CEH) – Interactions (merger) 50 kpc Msun 10 8 Msun in gas SFR ~ Msun/yr

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 10 Parr (1998,CISRO) Magellanic Stream H I Ram pressure Tidal stripping Bridge

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 11 New Proper Motions Besla et al. (2007) HST proper motions (QSOs) Two year separation New 3-space velocity (380 kms) Unbound!

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 12 HST SFH Smecker-Hane et al., 2002 Stellar evolution models Maximum likelihood fit to number of stars in each cell of CMD

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 13 LMC SFH Smecker-Hane et al., 2002 SFR (Msun/yr/sqdeg) Age (Gyr)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 14 Chemical Enrichment: Element Ratios Solar Abundance: Log10(n H )=12 Plot credit: NASA

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 15 -Element Ratios SNe Type I vs Type II Star formation history Chemical imprint in stellar abundance patterns

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 16 Johnson, et al. (2006) -Element Ratios LMC, Milky Way have distinct enrichment histories No local dwarf looks like components of the Milky Way WFMOS

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 17 SAGE and The Large Magellanic Cloud Add MLH to SFH+CEH -> Complete picture of a galaxy's evolution Life cycle of matter: Old stars ISM Young Stars Global SED, contributions from ext and point srcs Use the galaxy components to inform studies of SF at high redshift Overview: Meixner et al. (2006); Evolved stars: Blum et al. (2006)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium credit: Intermediate mass stars High mass stars Tracing the Life Cycle of Baryonic Matter:

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 19 Spitzer Launch August 25, 2003 (day 1332) Mission life 5 yr+ (Cycle 4 last full cycle)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 20 Spitzer 85 cm Telescope – DL 6.5um – LHe cooled (360 ltr) – Trailing Earth orbit (0.1 AU/yr) – Temp ~ 40 K

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 21 Spitzer Instruments IRAC (Infrared Array Camera), – 3.6 um, 4.5 um InSb – 6.5 um, 8.0 um SiAs – 5.12 arc minute FOV, 1.2'' pixels MIPS (Multi-band Imaging Photometer) – 128x128 SiAs 24 um, 32x32, 2x20 GeGa 70, 160 um – 2.5'', 5''/10'', 16'' pixels IRS (Infrared Spectrometer) – 5-40 um – R=50-600

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium Spitzer Instruments 2

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium SAGE Science: Key ISM Questions ISM in the LMC: – What are the properties and abundance of dust in different parts of the LMC? – What is the structure of the ISM in the LMC? Separate stars from extended emission, investigate H II, PDRs, MCs, diffuse ISM. Explore relationship of dust emission to UV and kinetic energy sources

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium SAGE key Star Formation questions: Star Formation in the LMC: – What is the galaxy-wide star formation rate of the LMC and how do the details vary on scales of a few pc? – GMC's: look for low mass or embedded SF – Do tidally-triggered star formation events sustain themselves by propagating through the ISM, or are they short-lived? Interplay between triggering and dispersal.

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium SAGE Science: Key Evolved Star Questions: Stellar Mass-loss Return to the LMC: – What is the mass budget of material injected into the ISM by evolved stellar winds? – How does stellar mass loss rate depend on stellar parameters: L, T eff, period, chemistry (C- or O- rich), Z? SFH+colors -> building blocks of high z galaxies

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 26 Spitzer SAGE survey in context of other LMC surveys Two epochs: Jul/Aug 05, Oct/Nov 05, 500 hr MIPS bands: 24, 70, 160 um, Fast Scan map, 38 legs of 25'x4 deg IRAC bands: 3.6, 4.5, 5.6, 8 um, 14x28 HDR 0.6s 12s per 1.1 deg tile CO HIHI HIHI IRASH alpha/MIPS UVStars/IRAC UV IRAS 100 um Ha Stellar density MCELS, Smith, Points et al.

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 27 Previous IR surveys of LMC IRAS: 12, 25, 60, 100 um (Schwering 1989) – 8.5x8.5 degree coverage – 1 arc minute angular resolution – 1823 object point source list MSX: 8 um (Egan, van Dyk & Price 2001) – 10x10 degree coverage – 20'' angular resolution – 1806 object point source list 2MASS: J, H, Ks (Nikolaev & Weinberg 2000) & DENIS I, J, H, Ks (Cioni et al. 2000) – ~2'' angular resolution – 820,000; 1.3 million

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 28 IRAC Tile, 3.6, 4.5, 8.0

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium MIPS Scan Maps

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 30 IRAC 3.6, 4.5, 8.0 C

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 31 MIPS 24, 70, 160

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 32 Hess Diagram LMC A-G SG Saturation J-band limit Foreground LMC OB TRGB AGB RGB

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 33 C-rich O-rich SG “Extreme” AGB, SG AGB->O-rich become C-stars during dredge up Lower Z, easier to get C/O > 1 Extreme stars mostly C-rich, but need spectra to decide

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 34 Models 1 Marigo (2002) C/O varies on TP-AGB Previous models used fixed, scaled, opacity (C/O=solar) New models have variable opacities Net result, C stars move to lower Teff (O-rich stars don't)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 35 Models 2 Ks J-Ks Cioni et al. (2006) use Marigo models to explain C-star locus in 2MASS CMD Define photometric selection of C-, M- stars

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 36 SAGE has IRAC plus 2MASS catalog, so we can define regions in NIR/MIR CMDs Four main evolved star types: – C-rich – O-rich – SG – Extreme O-rich C-rich SG Extreme [3.6] J - [3.6]

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 37 Spatial distributions match source types

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 38 Dust

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 39 Galaxies Lots of galaxies, “2MASS J-band drop outs”

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 40 SWIRE ELAIS N1 Approx 300 sources per square degree to [8.0]=13.5, Similar result using [8.0] and [24] Slightly more SAGE sources at [3.6], [8.0] Brighter sources in LMC - > YSOs

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium microns SAGE sees all important mass losing sources Lower L mass losing sources - > cool, dusty envelopes IRS spectra give dust envelope chemistry Buchanan et al. (2006)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 42

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 43 Mass Loss Rates van Loon et al., (1999)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 44 Mass Loss Rates Log10 (10 6 *Msun/yr) [24]

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 45 Kevin Volk Dust Shell Models

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 46 Model Grid Kevin Volk

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 47 Young Stellar Objects ?

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 48 Identifying and Analyzing on-going SF

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 49 N4 30” RGB=24,8,4.5um contours=cm continuum (RI et al. 2005) candidate YSOs: example 30'' Image courtesy of Rémy Indebetouw

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium CO from NANTEN, Fukui et al. Images courtesy of Rémy Indebetouw

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 51 The Global SED * * * All evolved stars

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 52 Carbon Rich AGB stars: 1.70E-03, 25% Oxygen Rich AGB stars: 1.70E-03, 25% Super giants ([3.6] < 10): 1.00E-03, 13% Extreme AGB: 2.60E-03, 37% Total: 7.00E-03, 100% Similar to SN rate (Chu & Kennicutt 1988) Mass Loss by type over Entire LMC (Msun/yr)

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 53 Summary SAGE completes galaxy evolution for the LMC, leveraging a vast archive of UV, Optical, IR, and radio data Detects ``all'' mass losing sources in galaxy Evolved stars are a very significant source of input to the ISM

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 54 Coming Soon: SAGE-SMC

April 18, 2007 R. Blum – University of Connecticut Physics Colloquium 55