From Molecular Cores to Planet- forming Disks: Overview and Recent Results from the Spitzer Space Telescope Neal J. Evans II University of Texas at Austin and the c2d Team

From Cores to Disks (c2d)

Science Goals  Complete database for nearby (< 350 pc), Low mass star and substar formation  Follow evolution from starless cores to planet- forming disks  Coordinate with FEPS team to ensure complete coverage of 0 to 1 Gyr  Cover range of other variables (mass, rotation, turbulence, environment, …) to separate from evolution.

Observations  (275 hr) IRAC and MIPS Mapping Map ~5 large clouds (~20 sq. deg.) Map ~5 large clouds (~20 sq. deg.) ~135 smaller cores ~135 smaller cores  (50 hr) IRAC and MIPS Photometry ~190 stars ~190 stars  (75 hr) Spectroscopy of disk material (IRS) about 200 targets about 200 targets  Ancillary/complementary data from optical to mm Collecting a very large data base Collecting a very large data base Will be publicly available eventually Will be publicly available eventually

Early Results from Spitzer  Mostly validation data (about 1% of total) Observed two small cores (IRAC/MIPS) Observed two small cores (IRAC/MIPS) One (L1228) with a known infrared sourceOne (L1228) with a known infrared source One (L1014) withoutOne (L1014) without Observed six IRS targets Observed six IRS targets B5 IRSB5 IRS HH46/47 IRS (with ERO team)HH46/47 IRS (with ERO team)  Recently received data (little analysis done) Ophiuchus, a few cores Ophiuchus, a few cores

A Typical Starless Core L1014 distance ~ 200 pc, but somewhat uncertain. R-band image from DSS

A Surprise from Spitzer Three Color Composite: Blue = 3.6 microns Green = 8.0 microns Red = 24 microns R-band image from DSS at Lower left. We see many stars through the cloud not seen in R. The central source is NOT a background star. L1014 is not “source-less”. Larger size in red is PSF. C. Young et al. ApJS, in press

Source Peaks on mm Emission Left: 8 micron on 1.2 mm MAMBO dust continuum emission (Kauffmann & Bertoldi) Right: 24 micron on 850 micron SCUBA data (Visser et al. 2002) Both long-wave maps are 3-sigma contours. C. Young et al. ApJS, in press

Models C. Young et al. ApJS, in press, Poster Model of SED for d = 200 pc. Central object has very low luminosity: 0.09 L sun. Requires BB plus disk (red line) in an envelope. M(envelope) about 2 M sun. Cannot be a stellar-mass object with significant accretion. Probably sub- stellar at this point. Alternative model: more distant (2.6 kpc) object lined up by chance with peak of a foreground core (dashed line)

Lessons from L1014  “Starless” cores may not be Or may have substellar objects Or may have substellar objects  Very low luminosity sources may exist Must be low mass and low accretion Must be low mass and low accretion Caveat: possible background source Caveat: possible background source  Are there others?

Check the Thumbprint Another “starless” core, the thumbprint nebula. Has scattered light all around periphery. Barely detected with ISO; consistent with heating only by the ISRF. See Lehtinen et al. 1998, Astr. Ap. 333,702.

Another clue? Blue is DSS-red, green is 24 microns, red is 70 microns MIPS data are very preliminary, not cleaned up. IRAC not available yet.

HH46/47 Outflow Structure Noriega-Crespo et al. ApJS, in press

Shock Spectrum Noriega-Crespo et al. ApJS, in press

Icy Dust Grains Boogert et al. ApJS, in press Spitzer IRS plus Keck/NIRSPEC or VLT/ISAAC Rich spectrum of ices: CO 2, H 2 O, CH 3 OH, OCN – and others. Can study ice evolution in regions forming sun- like stars. Little processing at T>50 K, some evidence for lower temperature processing.

Ices in low-mass stars

Spectral Evolution 10 My 100 My 5 Gy Few My

C2D IRS Validation Data Band positions, not ID CO2 H2O CH3OH+? Silicates NH3 CH4 CH3OH+? PAH E/FE EEE EFFF F FF FeO PAH PAH/F E/FE Silicates PAH? PAH E/F E E F F F F F F FeO PAH Silicates F

Debris Disks around wTTS Model has 0.1 M moon of 30  m size dust grains in a disk from 30–60 AU Bars are 3  Model based on disks around A stars Not enough data yet to say anything.

A Surprise from the wTTs RXJ Move from DSS to 24 microns in steps. Nondescript nearby star on DSS is the strong one at 24 microns. Which is the X-ray source?

Very Recent Data  Preliminary reduction  Minimal analysis

Ophiuchus A V = 3 and AORs Outline of A V = 3 IRACAORS MIPSAORs 1o1o1o1o

L1689 at 24 microns

High-extinction regions are dark at 24 microns Red: 24 micron emission, Blue: extinction from 2MASS and Weingartner and Draine extinction law, binned to 40” resolution. Cuts: Black is A V ; Red is emission

IRAC on L1689 Blue is IRAC-1 (3.6); Green is IRAC-2 (4.5); Red is IRAC-4 (8) Extremely preliminary, obtained data a few days ago.

Quick look at content… Very preliminary: Based solely on 2MASS and 24 microns, and comparison to Simbad.

Bolocam map of Ophiuchus K. Young et al. In prep Bolocam map (1.2 mm) of region in Spitzer survey. Covers very large area (> 10 sq. deg.) compared to any previous map. Rms noise ~ 50 mJy, with about half the data.

CG30/31 Cores Collection of cores in the Gum nebula (d ~ 200 pc).

MIPS-24

MIPS-70

Color Composite Blue is DSS-red Green is 24 microns Red is 70 microns Very preliminary reduction. No IRAC data available yet.

A Double Source L673: Red is Bolocam (1 mm); green is MIPS-70, blue is MIPS-24. String of cores with cluster of 24 micron sources, two red in main core.

Lots more to come…  Maps of Chamaeleon, Serpens delivered Working on data Working on data  About 20 small cores observed  Other clouds, many small cores  Photometry of stars  IRS targets