Alyssa A. Goodman, Principal Investigator (CfA), João Alves (ESO, Germany), Héctor Arce (AMNH), Tom Bethell (U. Wisc.), Michelle Borkin (Harvard College), Paola Caselli (Arcetri, Italy), James DiFrancesco (NRC-HIA, Canada), Jonathan Foster (CfA, PhD Student), Michael Halle (SPL-BWH/HMS), Mark Heyer (UMASS/FCRAO), Di Li (CfA/JPL), Jason Li (Harvard College), Doug Johnstone (NRC-HIA, U. Victoria, Canada), Helen Kirk (U. Victoria, Canada), David Kosslyn (BB&N High School), Marco Lombardi (ESO, Germany), Jaime Pineda (CfA, PhD Student), Naomi Ridge (CfA), Scott Schnee (CfA, PhD student), Mario Tafalla (OAN, Spain), Nathan Whitehorn (U. Chicago) Data from COMPLETE are made freely available at the Survey’s web site (take a Post-It Pad!) Also: “Phase I Data” Summary Paper (Ridge et al. 2006) is available online Data from COMPLETE are made freely available at the Survey’s web site (take a Post-It Pad!) Also: “Phase I Data” Summary Paper (Ridge et al. 2006) is available online Be on the lookout for: “All the Outflows in Perseus” (Arce et al.); COMPLETE++ Extinction Mapping (Lombardi & Alves, 2006) “Atomic Gas in the COMPLETE Molecular Clouds” (Li et al.); “The Real Rho-Oph Cluster, and Ring” (Li et al.); “Angular Momentum & Bulk Motion in Star-Forming Regions” (Schnee et al.); “Astronomical Medicine” (Goodman et al.); “Clumpfinding in Molecular Clouds” (Pineda et al.) Naomi Ridge Doug Johnstone Michelle Borkin Alyssa Goodman “Not all measures of column density are created equal.” Intercomparison of column density maps based on 13 CO integrated intensity, far-infrared dust emission, and near-infrared extinction mapping reveals that: extinction mapping is most intrinsically accurate; far-infrared emission maps can be custom-corrected to nearly match extinction maps (see panel at right); but 13 CO maps cannot be corrected to represent column density faithfully. The 13 CO emission is subject to both opacity and depletion effects at high column densities, and is sub-thermally excited at low column density, leading to column density maps that are impressionistically, but not quantitatively, accurate. The near-infrared and thermal emission maps show that, at least over the 10-square pc area of Perseus mapped in COMPLETE (see panel above), the distribution of column density is log-normal, as predicted by many theories of turbulence. (Goodman, Ridge & Schnee 2006). Scott Schnee “One temperatur e per pixel is not good enough!” Schnee, Bethell & Goodman 2006 find that the scatter in the relationship between emission- and extinction based measures of column density is primarily due to the assumption of line-of-sight isothermality. Schnee et al presents a method for optimizing far-IR-derived measures of column density using extinction-mapping for calibration. The middle and right panel above show that even after this optimization is carried out for the full COMPLETE fields, substantial scatter in the plots of Emission vs. Extinction measures of A V remains. The leftmost plot shows the result of a synthesized observation of a numerical simulation of a realistically turbulent cloud using the same wavelengths (60 and 100 microns), noise levels, and assumptions as in the COMPLETE analysis. Notice that the scatter in the simulation emulates the data--even though the dust in the simulation has a single value of the emissivity spectral index (b) throughout. Nearly all of the scatter is produced by the (false!) assumption of a single line-of-sight temperature in each map pixel. “Astronomical Medicine” In our quest to make the large (e.g. nearly 200,000 spectra in one Perseus map alone) COMPLETE data set intelligible to humans, we have, in collaboration with researchers at the Harvard-affiliated Brigham and Women’s Hospital in Boston, used the medical imaging tool known as “3-D Slicer” to interactively visualize spectral-line data cubes. We will also use the “segmentation” features of 3-D Slicer to develop a new clumpfinding algorithm that will allow for the identification and characterization of hierarchical features, rather than requiring a “space-filling” approach like the widely-used routine “CLUMPFIND” (by J. Williams). It is our expectation that the new clumpfinding procedure will be able to automatically identify more meaningful (e.g. bound) clumps, and will alter our understanding of the so-called “clump mass function” in molecular clouds. (Borkin et al. 2005, astro-ph; Goodman et al. 2006, for Nature) 13 CO in IC348 3-D Slicer View (contour overlay shows integrated intensity, B&W image is K-band) Standard (J. Williams) “CLUMPFIND” View of Same Region This work is also a pilot project of a new “Initiative in Innovative Computing” at Harvard. Ask Alyssa Goodman for more information, and WATCH THE MOVIE!!. Data Products, by Resolution ~1  J,H,K images of cores (Calar Alto, CTIO) ~10  sub-mm dust emission (JCMT/SCUBA); 1.2 mm dust emission (IRAM/MAMBO,c2d) ~20  N 2 H + etc. (IRAM) ~40  12 CO, 13 CO, CS, N 2 H + (FCRAO); NICER JHK Extinction Maps (Calar Alto, CTIO) ~5 ISSA (IRAS): NICER JHK Extinction (2MASS The “Coordinated Molecular Probe Line Extinction Thermal Emission Survey of Star Forming Regions” provides spectral-line, dust emission and dust absorption maps of the Perseus, Ophiuchus, and Serpens regions observed by Spitzer in the c2d Legacy Survey. “Phase 1” of COMPLETE, released Jan. 2006, provides fully-sampled maps at arcmin resolution; “Phase 2,” now well-underway, includes higher-resolution mapping of the most prominent star-forming cores in each region. Jaime Pineda Coverage in Perseus (background shows COMPLETE NICER Extinction Map, Ridge et al. 2006) Coverage and Resolution is similar in Ophiuchus & Serpens… See Jaime & his poster, # , for details on coverage, and clumpfinding Results. {Johnstone, DiFrancesco & Kirk 2004; Kirk, see also Kirk, Johnstone & DiFrancesco 2006) “Cores like cities.” COMPLETE SCUBA Mapping of Ophiuchus 20 times more extensive than earlier work (and only twice as shallow) showed that nearly all cores are found above a threshold of roughly A V =15 mag. (Notice how “empty” the 850  m map looks, above.) Modeling the clumps as Bonnor-Ebert spheres shows the lack of objects at low extinction is not due to detection sensitivity (see Fig. 1, at left). Even though we often think of Perseus as a long chain of dark clouds (e.g. as it appears in CO maps), its dust emission is dominated by a giant shell, filled with H  emission. The “finger” of extinction bifurcating the H  emission clearly indicates that the shell is behind the molecular clouds. Spectral-line and 8  m (MSX) data, not shown here, show that the shell & molecular gas are interacting on the “backside” of the clouds. Appreciation of the shell’s existence allows understanding of the apparently bi-modal magnetic field distribution, with one component associated with the warm ring (blue vectors) and the other with the cool clouds (red vectors). (Ridge et al. 2005, submitted) Jonathan Foster “Cloudshine” Dark Clouds Shine at 21st mag in J & H “Red” Outflows & Shining Dust Outflows glowing red with excited hydrogen and a small blue reflection nebula frame L1448 in the southwest of Perseus. Ambient starlight reflects off dust density features in this small star-forming cloud, providing an unprecedented high-resolution view of its complicated structure. (frame is 15 x 15) Internal Structure of Dust “Blobs” Revealed This overlay of our 1-mm (MAMBO/IRAM) dust map (contours) on our deep (Calar Alto) JHK color composite image shows how the near infrared literally highlights the edges of dense structures within molecular clouds. (frame is 15 x 15) Both images: J=blue, H=green; K=red A New Way to Map the Dense ISM with sub-arcsec Resolution [JHK data: Foster & Goodman 2005] (mm data: Tafalla et al. 2006) A Giant, Warm, Shell in Perseus is Poking at the Molecular Clouds from Behind Polarization on ExtinctionPolarization on Dust Emission © deg ~ 5 pc Offerings from the Survey of Star-Forming Regions See recent ApJ Letter (Foster & Goodman) for Modeling! Funded in part by the National Science Foundation.