AAS Topical Conference Series Workshop on Dense Cores: Origin, Evolution, and Collapse

27-30, July 2014 I Monterey, CA 100 – Plenary: Herschel Observations of Gould Belt Cores and Filaments Plenary Session – Grove – 28 Jul 2014 09:00 am to 09:45 am Chair(s): Paola Caselli (University of Leeds) 100.01 – Herschel Observations of Gould Belt Cores and Filaments The Herschel Space Observatory has provided us with unprecedented images of the initial and boundary conditions of the star formation process at far-infrared and submillimeter wavelengths. In particular, the Herschel data give key insight into the global properties of dense cores and the link between these properties and the structure of molecular clouds. I will give an overview of the results obtained in this area as part of the Herschel Gould Belt survey, one of the largest key projects with Herschel. The survey findings confirm the existence of a close relationship between the prestellar core mass function (CMF) and the stellar initial mass function (IMF). The Herschel images also reveal a rich network of filaments in every interstellar cloud and suggest an intimate connection between the filamentary structure of the ISM and the core formation process. Remarkably, filaments are omnipresent even in unbound, non-star-forming complexes and seem to be characterized by a narrow distribution of widths around ~ 0.1 pc, which roughly corresponds to the maximum observed size of prestellar cores. In active star-forming regions, most of the prestellar cores identified with Herschelare located within gravitationally unstable filaments above a critical threshold ~ 16 Msun/pc in mass per unit length, corresponding to Av ~ 8 in visual extinction or column density. Altogether, the Herschel results favor a scenario in which interstellar filaments and prestellar cores represent two fundamental steps in the star formation process: First, the dissipation of kinetic energy in large-scale MHD flows (turbulent or not) generates a complex web of filaments in the cold ISM; second, the densest filaments grow and fragment into prestellar cores (and ultimately protostars) by gravitational instability. Author(s): Philippe Andre1 Institution(s): 1. Centre d'Etudes de Saclay, Gif-sur-Yvette, Cedex, France, France. 101 – Plenary: Filamentary Flows Plenary Session – Grove – 28 Jul 2014 09:45 am to 10:30 am Chair(s): Paola Caselli (University of Leeds) 101.01 – Filamentary Flows Observations over the last few years, especially those from the Herschel Space Telescope have shown that filaments are intimately connected with dense cores. Both theory and observations are starting to suggest that filaments may provide an important reservoir of material both in the accretion of relatively isolated dense cores found along filaments, as well cluster-forming

cores, which tend to be found at the junction of multiple filaments. I will review some of the recent evidence of gas flows in filaments, highlighting results from the young Serpens South cluster-forming region. I will also touch on recent analysis of numerical simulations which suggests a similar behavior. Author(s): Helen Kirk1 Institution(s): 1. Harvard Smithsonian Center for Astrophysics, Cambridge, MA. 102 – Plenary: High resolution NH3 studies of nearby star-forming regions Plenary Session – Grove – 28 Jul 2014 11:00 am to 11:45 am Chair(s): Paola Caselli (University of Leeds) 102.01 – High resolution NH3 studies of nearby star-forming regions Stars form within dense molecular cores. These cores are often embedded within larger structures, such as clumps and filaments, particularly in clustered star-forming environments. Indeed, large-scale maps of the continuum emission from dust have revealed the ubiquity of filaments in star-forming regions. The condensation and fragmentation of cores within larger structures is therefore a critical step in the star formation process, but continuum data alone do not provide key information, such as the gas kinematics, needed to discern between evolutionary scenarios. I will present new results from large NH3 studies of nearby star-forming regions, including Taurus and Serpens South. While NH3 primarily traces high density gas, sensitive observations over Serpens South reveal extensive, low brightness emission between the prominent cores and filaments, and show directly the frequently (but not invariably) sharp transitions between turbulent and quiescent gas in the high density regions. I will discuss the hierarchical structure of the dense gas in Serpens South, with comparisons between two- and three-dimensional analysis, and analyze the importance of thermal fragmentation in the filaments and cores over a range of physical scales. Author(s): Rachel Friesen1 Institution(s): 1. National Radio Astronomy Observatory, Charlottesville, VA. 103 – Monday Session 1 Oral Session – Grove – 28 Jul 2014 11:45 am to 12:05 pm Chair(s): Paola Caselli (University of Leeds) 103.01 – Chains of Dense Cores in the Taurus L1495/B213 Complex We study the formation of dense cores in the filamentary L1495/B213 region of Taurus. Observations of its C18O emission show that what appears as a single 10pc-long filament in optical and continuum images is in fact a complex web of smaller filamentary structures that we call fibers. These fibers are typically 0.5~pc long and velocity coherent, and seem to have decoupled from the turbulent velocity field of the large-scale cloud. Fibers appear as the true parent structures of the cores, but only a small subset of them seem able to form cores ("fertile fibers") while the rest remain sterile. The fertile-sterile dychotomy of fibers is striking, since sterile fibers do not form cores but fertile fibers form three cores on average. As a result, most cores in the L1495/B213 region are part of linear groups or chains that have a typical core

spacing of 0.1pc. Our observations and analysis suggest that core formation out of a large-scale filament is a two-step process that involves first the dissipation of turbulence via shock interaction and then the fragmentation of those disspated structures that exceed the mass per unit length limit of gravitational instability. Author(s): Mario Tafalla1, Alvaro Hacar2 Institution(s): 1. Observatorio Astronomico Nacional (OAN), Spain, Madrid, Madrid, Spain. 2. Institute for Astrophysics, University of Vienna, Vienna, Vienna, Austria. 104 – Plenary: Infrared and Submilllimeter Studies of Dense Cores Plenary Session – Grove – 28 Jul 2014 01:35 pm to 02:20 pm Chair(s): Paola Caselli (University of Leeds) 104.01 – Infrared and Submilllimeter Studies of Dense Cores Dense Cores are the birthplace of stars, and so understanding their structure and evolution is key to understanding star formation. Information on the density, temperature, and motions within cores are needed to describe these properties, and are obtained through continuum and line observations at far infrared and submm/mm wavelengths. Recent observations of dust emission with Herschel and molecular line observations with single-dish telescopes and interferometers provide the wavelength coverage and resolution to finally map core properties without appealing to spherical simplifications. Although large scale Herschel observations reveal numerous filaments in molecular clouds which are well described by cylindrical geometries, cores are still modeled as spherical entities. A few examples of other core geometries exist in the literature, and the wealth of new data on cloud filaments demand that non-spherical models receive more attention in future studies. This talk will examine the evidence for non-spherical cores and their connection to the filaments from which they form. Author(s): Tyler L. Bourke1 Institution(s): 1. Harvard-Smithsonian, CfA, Cambridge, MA. 105 – Plenary: Theory and Numerical Simulations of Self-Gravitating Core Formation Plenary Session – Grove – 28 Jul 2014 02:20 pm to 03:05 pm Chair(s): Paola Caselli (University of Leeds) 105.01 – Theory and Numerical Simulations of Self-Gravitating Core Formation In star-forming molecular clouds, dense cores grow and evolve due to a combination of supersonic turbulent compression and self-gravity, with the details of the dynamical processes mediated by magnetic stresses and ion-neutral drift. In classical theory, cores with sufficiently high gravitational energy compared to thermal and magnetic support undergo outside-in collapse to reach a state in which the density profile approaches a singular r^-2 power law. This collapse is evident in numerical simulations, for a wide range of initial and environmental conditions. Classical theory predicts a subsequent outside-in infall stage, which is also seen in simulations. I will discuss numerical hydrodynamic and magnetohydrodynamic simulations of core formation and evolution, concentrating on evolution up to the stage of singularity formation. Observations show that cores are found to lie within larger-scale filaments, and

simulations indicate that these filaments grow at the same time as cores develop within them. Although magnetic fields are often been thought of as a significant barrier to star formation that must be surmounted via ambipolar diffusion, recent simulations show that the properties of cores formed in hydrodynamic, ideal MHD, and diffusive models are quite similar. I will discuss how this can be understood in terms of anisotropic core formation models. Author(s): Eve C. Ostriker1 Institution(s): 1. Univ. of Maryland, College Park, MD. 106 – Monday Session 2 Oral Session – Grove – 28 Jul 2014 03:05 pm to 03:45 pm Chair(s): Paola Caselli (University of Leeds) 106.01 – Formation and evolution of cores in globally collapsing environments I will present recent results on the hierarchical gravitational fragmentation (HGF) of molecular clouds (MCs) leading to the formation of dense cores. I will first discuss the scenario of HGF as an alternative to the standard scenario of turbulent support --> turbulent dissipation --> collapse. In it, clouds are multi-Jeans-mass object undergoing global, multi-scale collapse, and the cores are the local centers of collapse. The lapse between the onset of local collapse and the formation of a singularity constitutes the prestellar phase. I will present numerical simulations of core growth during this phase in the idealized case of spherical geometry, immersed in a globally collapsing environment, discussing the evolution of the density and velocity profiles. I will also present synthetic molecular line observations of such idealized cores, aimed at determining to what extent such an idealized setup recovers the basic observational features of the cores, and which features require additional physics such as background turbulence and non-spherical symmetry. Author(s): Enrique Vazquez-Semadeni1 Institution(s): 1. UNAM, Morelia, Michoacan, Mexico, Mexico. 106.02 – Formation of Dense Clumps/Cores in Infrared Dark Clouds and Their Magnetic Field Properties from AMR MHD Numerical Simulations Massive infrared dark clouds (IRDCs) are believed to be the precursors to star clusters and massive stars (e.g. Bergin & Tafalla 2007). The supersonic turbulent nature of molecular clouds in the presence of magnetic fields poses a great challenge in understanding the structure and dynamics of molecular clouds and the star formation therein (e.g. Falgarone et al. 2008, Crutcher et al. 2010, Peretto & Fuller 2010, Hernandez & Tan 2011, Harcar et al. 2013, Kainulainen & Tan 2013). We perform two high resolution ideal MHD AMR simulations with supersonically driven turbulence on the formation of massive infrared dark clouds, using our radiative-MHD AMR code ORION2 (P.S. Li, et al. 2012), to reveal the complex 3D filamentary structure and the subsequent formation of dense clumps and cores inside the dark clouds. The two models differ only in field strength, with one model having an initial field 10 times as strong as the other. The magnetic properties of the clumps from the two models are compared with the Zeeman observations summarized in Crutcher et al. (2010). Our dense clumps exhibit a power-law relation between magnetic field strength and density similar to the observations.

Despite the order of magnitude difference in initial field strength, with the magnetic field enhancement and fragmentation as the result of turbulence, the magnetic properties of clumps in the weak field model are remarkably similar to those in the strong field model, except for a clear difference in the magnetic field orientation with respect to the global mean field direction. The almost random orientation of the weak field simulation is inconsistent with the observation of the field orientation on large and small scales by H.-b. Li, et al. (2009). I will briefly summarize the physical properties of the filamentary dark clouds in the simulations and report a detailed comparison of the magnetic properties of dense clumps in the simulations with the Zeeman observations. We have continued the strong field model simulation with radiation transfer and proto-stellar wind feedback, and I will present some preliminary results on how radiation and wind feedback affect the dense clumps and filaments surrounding the protostars. Author(s): Pak Shing Li1, Richard I. Klein1, 3, Christopher F. McKee1, 2 Institution(s): 1. Astronomy Department, University of California at Berkeley, Berkeley, CA. 2. Physics Department, University of California at Berkeley, Berkeley, CA. 3. Lawrence Livermore National Laboratory, Livermore, CA. 107 – Monday Session 3 Oral Session – Grove – 28 Jul 2014 04:00 pm to 06:00 pm Chair(s): Paola Caselli (University of Leeds) 107.01 – A Search For Fragmentation in Starless Cores with ALMA The majority of Class 0 protostars are found in multiple (binary or higher order) systems, but it is uncertain if protostellar multiplicity has its origin in the fragmentation of starless cores or if fragmentation typically occurs after the formation of the first protostar. Here we present a deep (0.01 M_sun), high resolution (3”) ALMA survey of every starless core in the Chamaeleon I molecular cloud. We have mapped the 3mm continuum emission and CO (1-0) towards a sample of over 70 cores, making this the largest search for fragmentation in starless cores to date. Author(s): Scott Schnee1, Hector Arce2, Tyler Bourke3, Xuepeng Chen4, 2, James Di Francesco5, Michael Dunham6, Doug Johnstone5, Stella Offner2, Jaime Pineda7, Daniel Price9, Sarah Sadavoy8 Institution(s): 1. NRAO, Charlottesville, VA. 2. Yale, New Haven, CT. 3. Square Kilometre Array Organisation, Manchester, United Kingdom. 4. Purple Mountain Observatory, Nanjing, China. 5. NRC-HIA, Victoria, BC, Canada. 6. Harvard Smithsonian CfA, Cambridge, MA. 7. ETH, Zurich, Switzerland. 8. MPIA, Heidelberg, Germany. 9. Monash University, Melbourne, VIC, Australia. 107.02 – Large Area, High Resolution N2H+ studies of dense gas in the Perseus and Serpens Molecular Clouds Star formation in molecular clouds occurs over a wide range of spatial scales and physical densities. Understanding the origin of dense cores thus requires linking the structure and kinematics of gas and dust from cloud to core scales. The CARMA Large Area Star Formation Survey (CLASSy) is a CARMA Key Project that spectrally imaged five diverse regions of the

Perseus and Serpens Molecular Clouds in N2H+ (J=1-0), totaling over 800 square arcminutes. The observations have 7’’ angular resolution (~0.01 pc spatial resolution) to probe dense gas down to core scales, and use combined interferometric and single-dish data to fully recover line emission up to parsec scales. CLASSy observations are complete, and this talk will focus on three science results. First, the dense gas in regions with existing star formation has complex hierarchical structure. We present a non-binary dendrogram analysis for all regions and show that dense gas hierarchy correlates with star formation activity. Second, well-resolved velocity information for each dendrogram-identified structure allows a new way of looking at linewidth-size relations in clouds. Specifically, we find that non-thermal line-of-sight velocity dispersion varies weakly with structure size, while rms variation in the centroid velocity increases strongly with structure size. We argue that the typical line-of-sight depth of a cloud can be estimated from these relations, and that our regions have depths that are several times less than their extent on the plane of the sky. This finding is consistent with numerical simulations of molecular cloud turbulence that show that high-density sheets are a generic result. Third, N2H+ is a good tracer of cold, dense gas in filaments; we resolve multiple beams across many filaments, some of which are narrower than 0.1 pc. The centroid velocity fields of several filaments show gradients perpendicular to their major axis, which is a common feature in filaments formed from numerical simulations of planar converging, turbulent flows. All of these initial results imply that over-dense, sheet-like regions in molecular clouds fragment into filaments, and build up hierarchical structures on the pathway to forming dense cores. Author(s): Shaye Storm1, Lee Mundy1, Eve Ostriker2, Leslie Looney3, Manuel Fernandez-Lopez3, Katherine Lee1, 3, Hector Arce4, Erik Rosolowsky5, Che-Yu Chen1, Peter Teuben1 Institution(s): 1. University of Maryland, College Park, MD. 2. Princeton University, Princeton, NJ. 3. University of Illinois, Urbana–Champaign, IL. 4. Yale University, New Haven, CT. 5. University of Alberta, Edmonton, AB, Canada. Contributing team(s): The CLASSy Collaboration 107.03 – Formation of interstellar filaments: the role of magnetic fields The filamentary structure of interstellar matter and its potential link to star formation has been brought back into focus recently by high resolution observational surveys. The densest of these filaments host pre-stellar and star forming cores, so explaining their properties is tightly correlated to revealing the initial conditions for star formation. To that end, in this work we employ high-resolution, 3D MHD simulations performed with the AMR code RAMSES to investigate two filament formation mechanisms: turbulence and sheet fragmentation. The first series of simulations has as a particular aim to address the origin of the characteristic filament thickness found in observations. Starting from the hypothesis that diffusive processes are responsible, our numerical experiments consist of (driven or decaying) ideal and non-ideal MHD turbulence, at a resolution that greatly exceeds the reported 0.1pc thickness. The comparison points to ion-neutral friction as an excellent candidate for setting a characteristic scale. In this picture dense filaments are the diffusive end of the turbulent cascade, an interpretation with important implications for our understanding of the dynamical behavior of the ISM. A second series of simulations investigates filament formation by the fragmentation of supershells, a scenario inspired by the analytical work of Nagai (1998). We find a striking difference between

hydrodynamical and MHD runs as in the first case the sheets fragment into small cores, while in the latter they produce large filaments. In addition though, we see that low-density filaments preferentially form along the dominant component of the magnetic field. In this scenario filaments are prominent features in the ISM, but their fate is still determined by the local magnetic field. A detailed comparison of the filament properties between the two runs is work in progress and will reveal the physical mechanisms responsible for shaping the ISM and setting the initial conditions for star formation. Author(s): Evangelia Ntormousi1, Patrick Hennebelle1, Philippe Andre1 Institution(s): 1. CEA, Gif-sur-Yvette, France. 107.05 – Study for Planck Cold Clumps with molecular lines To probe dynamical processes and physical properties of Planck Cold Clumps, we have observed 674 of the most reliable 915 sources with J=1-0 of CO,13CO and C18O using PMO 13.7 m telescope of Purple Mountain Observatory. J=1-0 lines of HCO+ and HCN at CO emission peaks were also observed, of which 24 were mapped with IRAM 30 m telescope. Results show excitation temperatures are from 4 to 17 K, and column densities range from 1020 to 4.5x1023 cm-2. Planck cold clumps have the smallest line width among samples of IRDCs, weak IRAS, EGOs, UC HII candidates and methanol maser chosen cores. However the lines are still wider than those of low-mass cores and have non-thermal supersonic dispersion. Filament is the majority in their morphologies and fragmented structures were found with dense molecular lines. More than 70% of CO cores are starless. Planck cold clumps seem to be ideal samples to search for candidates of massive prestellar cores and pre-clusters. Author(s): Yuefang Wu1 Institution(s): 1. Peking University, Haidian, Beijing, China. 108 – Posters 108.01 – Collapse and Fragmentation of Magnetic Molecular Cloud Cores with the Enzo AMR MHD Code. II. Prolate and Oblate Cores We present the results of a large suite of three-dimensional (3D) models of the collapse of magnetic molecular cloud cores using the adaptive mesh refinement (AMR) code Enzo2.2 in the ideal magnetohydrodynamics (MHD) approximation. The cloud cores are initially either prolate or oblate, centrally condensed clouds with masses of 1.73 or 2.73 solar masses, respectively. The radial density profiles are Gaussian, with central densities 20 times higher than boundary densities. A barotropic equation of state is used to represent the transition from low density, isothermal phases, to high density, optically thick phases. The initial magnetic field strength ranges from 6.3 to 100 microGauss, corresponding to clouds that are strongly to marginally supercritical, respectively, in terms of the mass to magnetic flux ratio. The magnetic field is initially uniform and aligned with the clouds' rotation axes, with initial ratios of rotational to gravitational energy ranging from 0.0001 to 0.1. Two significantly different outcomes for collapse result: (1) formation of single protostars with spiral arms, and (2) fragmentation into multiple protostar systems. The transition between these two outcomes depends primarily on the initial magnetic field strength, with fragmentation occurring for mass to flux ratios greater than about 14 times the critical ratio. Oblate clouds typically fragment into twice as many

clumps as the prolate clouds. Multiple system formation is the rule in either case, suggesting that binary stars are primarily the result of the orbital dissolution of multiple protostar systems. Author(s): Alan P. Boss1, Sandra A. Keiser1 Institution(s): 1. Carnegie Inst. of Washington, Washington, DC. 108.02 – We present 'Black Holes Make Stars which Explains the Mystery of the Newly Discovered Phoenix Galaxy while Dark Matter in the Universe is described in our Explanation.' We present an entirely new concept for 'How the universe and its contents might have formed.' We contend the Big Bang (BB) resulted from one (or two) Black Hole(s) (BH) bursting (or colliding), producing an almost infinite number of particles of varying sizes, from the smallest elementary particle to particles large enough to contain the mass of a galaxy. The accepted prevailing theory for stellar evolution is 'sufficiently massive stars are reduced to BH upon their ultimate demise.' We consider larger types of BH originating from the original BB, which are subsequently expanded and modified enough to start significant radiation and burst, which resulting particle eventually result into a Galaxy; and smaller BH which become stars and planets. We theorize the universe was made by a massive BH which had enough mass to produce the contents of our universe. We define and categorize BH by their mass and the spaces which they inhabit. We describe mechanisms for their formation and mechanisms of BH collisions and bursts, inside the universe, linked to formations of galaxies, stars, planets and moons. Our concept could explain the mystery of the newly discovered Phoenix Galaxy, which produces 740 Stars per year, an order of magnitude above expected. We propose that a category-1 (c-1) BH formed the universe, by generating c-2 BH which form galaxies, c-3 BH which form stars, and c-4 BH which form planets and moons. Each sequential category of BH is less dense, and is more expanded and modified; and links the formation of the universe to present day activities and processes observed on earth, especially leading to the formation of the elements on earth. We offer three mechanisms (a, b, & c) for stellar origin, formation and evolution. 'a' is the accepted 'accretion and gravitation process.' 'b' is 'as a star originates as an expanded, modified BH with none or little help from accretion, begins to radiate; and continues to grow into a star. 'c' is a mechanism in which a star originates from a combination of a & b which is most common. This also explains how super-cluster complexes, estimated to take 40 to 60 billion years to form, can occur in much less time, less than 14 billion years. Our Explanation is at our poster. Author(s): Salvatore Cimorelli1, Charles Samuels1 Institution(s): 1. Energetic Technologies, Phoenixville, PA. 108.03 – Properties of Starless Clumps through Protoclusters from the Bolocam Galactic Plane Survey High mass stars play a key role in the physical and chemical evolution of the interstellar medium, yet the evolution of physical properties for high-mass star-forming regions remains unclear. We sort a sample of ~4668 molecular cloud clumps from the Bolocam Galactic Plane Survey (BGPS) into different evolutionary stages by combining the BGPS 1.1 mm continuum and observational diagnostics of star-formation activity from a variety of Galactic plane surveys: 70

um compact sources, mid-IR color-selected YSOs, H2O and CH3OH masers, EGOs, and UCHII regions. We apply Monte Carlo techniques to distance probability distribution functions (DPDFs) in order to marginalize over the kinematic distance ambiguity and calculate distributions for derived quantities of clumps in different evolutionary stages. We also present a combined NH3 and H2O maser catalog for ~1590 clumps from the literature and our own GBT 100m observations. We identify a sub-sample of 440 dense clumps with no star-formation indicators, representing the largest and most robust sample of pre-protocluster candidates from a blind survey to date. Distributions of I(HCO+), I(N2H+), dv(HCO+), dv(N2H+), mass surface density, and kinetic temperature show strong progressions when separated by evolutionary stage. No progressions are found in size or dust mass; however, weak progressions are observed in area > 2 pc^2 and dust mass > 3 10^3 Msun. An observed breakdown occurs in the size-linewidth relationship and we find no improvement when sampling by evolutionary stage. Author(s): Brian E. Svoboda1, Yancy Shirley1, 2, Erik Rosolowsky3, Timothy Ellsworth-Bowers4, Adam Ginsburg5, Miranda Dunham6, Michele Pestalozzi7, Jason Glenn4 Institution(s): 1. Steward Observatory, University of Arizona, Tucson, AZ. 2. National Radio Astronomy Observatory, Charlottesville, VA. 3. University of Alberta, Edmonton, AB, Canada. 4. University of Colorado, Boulder, CO. 5. European Southern Observatory, Munich, Bavaria, Germany. 6. Yale, New Haven, CT. 7. University of Gothenberg, Gothenberg, Västergötland and Bohuslän, Sweden. Contributing team(s): Bolocam Galactic Plane Survey Team 108.04 – Spectroscopic infrared extinction mapping as a probe of grain growth in IRDCs We present photometric and spectroscopic tests of MIR to FIR extinction laws toward IRDC G028.36+00.07, a potential site of massive star formation. Lim & Tan (2014, hereafter LT14) developed methods of FIR extinction mapping of this source using Spitzer-MIPS 24 micron and Herschel-PACS 70 micron images, and extending the MIR 8 micron mapping methods of (Butler & Tan 2012, hereafter BT12), finding evidence for grain growth in the highest mass surface density regions. Here we present initial results of spectroscopic infrared extinction (SIREX) mapping using Spitzer-IRS (14 to 38 micron) data of the same IRDC. These methods allow us to measure the SED of the diffuse Galactic ISM, which we compare to theoretical models of Draine & Li (2007), as well as to search for opacity law variations with mass surface density within the IRDC. By comparison with theoretical dust models, e.g., Ossenkopf & Henning (1994) and Ormel et al. (2011), we are able to search for compositional signatures of the grain ices, such as water and methanol. We find evidence for generally flatter MIR to FIR extinction laws as mass surface density increases, strengthening the evidence for grain and ice mantle growth in higher density regions. Author(s): Wanggi Lim1, 2, Sean J. Carey2, Jonathan C. Tan1, 3 Institution(s): 1. Department of Astronomy, University of Florida , Gainesville, FL. 2. Infrared Processing and Analysis Center, Pasadena, CA. 3. Department of Physics,University of Florida, Gainesville, FL.

108.05 – ON THE INTERNAL DYNAMICS OF STARLESS CORES: STABILITY OF STARLESS CORES WITH INTERNAL MOTIONS AND COLLAPSE DYNAMICS In order to understand the collapse dynamics of observed low-mass starless cores, we revise the conventional stability condition of hydrostatic Bonnor-Ebert spheres to take internal motions into account. Because observed starless cores resemble Bonnor-Ebert density structures, the stability and dynamics of the starless cores are frequently analyzed by comparing to the conventional stability condition of a hydrostatic Bonnor-Ebert sphere. However, starless cores are not hydrostatic but have observed internal motions. In this study, we take gaseous spheres with a homologous internal velocity field and derive stability conditions of the spheres utilizing a virial analysis. We propose two limiting models of spontaneous gravitational collapse: the collapse of critical Bonnor-Ebert spheres and uniform density spheres. The collapse of these two limiting models are intended to provide the lower and the upper limits, respectively, of the infall speeds for a given density structure. The results of our study suggest that the stability condition sensitively depends on internal motions. A homologous inward motion with a transonic speed can reduce the critical size compared to the static Bonnor-Ebert sphere by more than a factor of two. As an application of the two limiting models of spontaneous gravitational collapse, we compare the density structures and infall speeds of the observed starless cores L63, L1544, L1689B, and L694-2 to the two limiting models. L1689B and L694-2 seem to have been perturbed to result in faster infall motions than for spontaneous gravitational collapse. Author(s): Youngmin Seo1, Yancy L. Shirley1, Seung Soo Hong2 Institution(s): 1. University of Arizona, Tucson, AZ. 2. Seoul National University, Seoul, Korea, Republic of. 108.06 – The Relationship Between Dense Cores, Filaments, and YSOs in the Perseus and Serpens Molecular Clouds The CARMA Large Area Star Formation Survey (CLASSy) provides a broad overview of the molecular emission from dense gas distribution in a total of five regions in the Perseus and Serpens Molecular Clouds with 7" angular resolution. These regions span a wide range of star formation activity, allowing a detailed comparison of the dense gas, dust, and young stellar object distributions on the scales from thousands of AU to 1-2 parsecs. This poster will specifically looks at the relationship between dense cores, filaments, and YSO's in these regions. Author(s): Lee G. Mundy1, Shaye Storm1, Manuel Fernandez-Lopez2, Katherine Lee1, Leslie Looney2, Eve Ostriker3, Hector Arce4, Eric Rosolowsky5 Institution(s): 1. Univ. of Maryland, College Park, MD. 2. University of Illinois, Urbana-Champaign, IL. 3. Princeton University, Princeton, NJ. 4. Yale University, New Haven, CT. 5. University of Alberta, Edmonton, AB, Canada. Contributing team(s): the CLASSy Team

108.07 – Mapping Collapsing Cores in Scattered Light: HST NICMOS+WFC3 Imaging of Orion Protostars A long standing question in the study of protostellar collapse is what halts the infall of a core onto a central protostar. Is the core eventually exhausted by infall, or does feedback from accretion-driven outflows disperse the core? Perhaps the best tracer of the impact of the outflow on the cores are the observed cavities carved by the outflows. We present a systematic study of near-infrared HST NICMOS+WFC3 1.6 micron images, mapping light scattered by dust grains in collapsing cores around low mass protostars with 80 AU resolution. These images are a component of HOPS, the Herschel Orion Protostar Survey, a multi-observatory survey designed to obtain 1-870 micron photometry, spectroscopy and imaging of a large sample of protostars in the Orion molecular clouds. Orion is home to half of the known protostars within 500 parsecs and is a largely unexplored ground for scattered-light studies of protostellar cores and disks. With 304 targets from the HOPS program imaged by the HST, we obtained a large sample of sources with resolved scattered light nebulae. The high spatial resolution allows us to determine properties of the protostars and collapsing cores that are not well constrained by the 1-870 micron spectral energy distributions. In particular, we map the profile of the outflow cavities for 25 sources by applying a variation of traditional edge detection techniques to the scattered light images and to radiative transfer models with known cavity geometries. From this, we estimate the fractional volumes of the collapsing cores dispersed by the outflows. Author(s): Joseph J. Booker1, Thomas Megeath1, William Fischer2, Marina Kounkel3, Charles Poteet4 Institution(s): 1. Department of Physics and Astronomy, University of Toledo, Toledo, OH. 2. Oberlin College, Oberlin, OH. 3. University of Michigan, Ann Arbor, MI. 4. Rensselaer Polytechnic Institute, Troy, NY. Contributing team(s): Herschel Orion Protostar Survey 108.08 – Kinematics of envelopes around First Core Candidates Simulations of star formation predict the formation of a young object that reaches hydrostatic equilibrium before the formation of the protostar. This first hydrostatic core which is a flattened, thermally supported structure with a size of a few AU will collapse after up to 10,000 years to form a second object in hydrostatic equilibrium, namely a (Class 0) protostar. We are studying a sample of eight first core candidates that have been identified as such based on the detection of a point source millimeter continuum emission very weak, or no continuum emission at ?<24 ?m and/or the presence of a low velocity outflow. Here, we present CARMA (NH2D, N2H+, HCO+, HCN) and ALMA (N2H+) molecular lines emission maps at a resolution of 500 to 1000 AU. At this scale we are able to study the kinematic and morphology of the dense envelope surrounding the first core candidates. The data show presence of infall and rotation. We study the kinematics of these sources by modeling the profile of the lines. We are studying the kinematics of these sources using a simple radiative transfer model. The data show presence of infall and rotation, and we aim to constrain the mass inside the resolution limit by modeling the velocity distribution of each envelope. This, along other properties (e.g., density profile, SED, level of deuteration) will help us constrain the evolutionary stage of these sources.

Author(s): Maria Jose Maureira1, Hector G. Arce1, Michael M. Dunham2, Diego Mardones5, Manuel Fernandez-Lopez6, Scott Schnee3, Jaime E. Pineda4, Diego Mardones5, Xuepeng Chen7, Tyler Bourke2, 8, Daniel Price9 Institution(s): 1. Department of Astronomy, Yale University, New Haven, CT. 2. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA. 3. National Radio Astronomy Observatory, Charlottesville, VA. 4. Institute for Astronomy, ETH Zurich, Zurich, Switzerland. 5. Departamento de Astronomia, Universidad de Chile, Santiago, Chile. 6. Instituto Argentino de Radioastronomia, Berazategui, Prov. de Buenos Aires, Argentina. 7. Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, Jiangsu, China. 8. SKA Organisation, Jodrell Bank Observatory, Manchester, Cheshire, United Kingdom. 9. Monash Centre for Astrophysics, Monash University, , VIC, Australia. 108.09 – Detection of ethylene glycol - toward W51/e2 and G34.3+0.02 Ethylene glycol (HOCH2CH2OH), also commenly known as antifreeze, is the reduced alcohol version of glycolaldehyde (CH2OHCHO). Glycoladehyde - the simplest possible aldehyde sugar (Marstokk and Møllendal 1973) - is the first intermediate step in the path toward forming more complex and biologically relevant molecules through the the formose reaction, which begins with formaldehyde (H2CO) and ends with the formation of sugars and ultimately ribose, the backbone of RNA (e.g., Larralde et al. 1995). The presence of glycolaldehyde is therefore an important indication that processes leading to biologically relevant molecules are taking place. It is however, still unclear as to how glycolaldehyde and ethylene glycol are formed in the ISM. It has been proposed that they share a common formation pathway through UV-irradiation of methanol (CH3OH) ices mixed with CO (Öberg et al. 2009). So far, ethylene glycol, in its lower energy con-former (g’Ga(CH2OH)2), has been detected toward SgrB2 (N) by Hollis et al. (2002), tentatively toward IRAS 16293-2422 (Jørgensen et al. 2012) and marginally by Kalenskii and Johansson (2010) toward W51 e1/e2. Here we present a firm detection of ethylene glycol toward W51/e2 as well as a first detection toward G34.3+0.02 at 1mm and 3mm using the IRAM 30m telescope. Author(s): Julie M. Lykke1, 2, Cécile Favre3, Edwin A. Bergin3, Jes K. Jørgensen1, 2 Institution(s): 1. Niels Bohr Institute, Centre for Star and Planet Formation, University of Copenhagen, Copenhagen, Denmark. 2. Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark. 3. Department of Astronomy, University of Michigan, Ann Arbor, MI. 108.10 – A Search for Very Low Luminosity Objects in Gould Belt clouds We present the results of a search for Very Low Luminosity Objects (VeLLOs) in the Gould Belt clouds using infrared observations from 1.25 to 70 micron by the Spitzer Space Telescope and 2MASS. More than 140 VeLLO candidates were selected through the criteria by Dunham et al. and this study.The candidates were then tested if they are embedded in their gas envelopes as Galactic sources with observations of N2H+ (J=1-0), a high density tracer, and archival Herschel data. From this study 55 new candidate VeLLOs were discovered. We investigate the spatial distribution of all existing VeLLO candidates in the clouds, finding that about 49 % of sources are located within dense regions of the clouds while the remaining 51 % are outside the clouds.

The VeLLOs within the clouds tend to have envelope masses of > 0.1 Msun while the sources outside clouds have masses of < 0.1 Msun, suggesting that their birth places are closely related to their envelope masses. We found that the numbers of YSOs and VeLLOs in all clouds are fairly well correlated. This indicates that the forming processes of the VeLLOs may be similar to those of normal stars.The bolometric luminosity and temperature of the VeLLO candidates are compared with predictions of episodic accretion models, showing that the low luminosities for most VeLLOs can be explained by their status in a quiescent phase between their episodic mass accretion. However, there are also a significant number of VeLLOs with very low envelope masses and lower luminosities than predicted by the episodic accretion models.They are likely either extragalactic contaminants or proto-brown dwarfs. Author(s): Mi-Ryang Kim1, 5, Chang Won Lee1, Michael M. Dunham2, Gwanjeong Kim1, 4, Neal J. Evans3, Lori E. Allen6 Institution(s): 1. KASI, Daejeon, Korea, Republic of. 2. CfA, Cambidge, MA. 3. The University of Texas at Austin, Austin, TX. 4. UST, Daejeon, Korea, Republic of. 5. CBNU, Cheongju, Korea, Republic of. 6. NOAO, Tucson, AZ. 108.11 – A single dish survey for outflow activity in the Very Low Luminosity Object candidates Very Low Luminosity Object (VeLLO) is a very faint ( Lint ? 0.1 L?) object deeply embedded in dense molecular clouds. This is important to study the precursors of low-mass or substellar objects because some of VeLLOs can be very faint protostars or others can be proto-brown dwarfs. The study of the molecular outflow in the VeLLOs will give us a hint to infer how accretion is being made around the VeLLOs, to diagnose present status and future fate of them, and to understand the origin of the formation of low-mass or substellar objects. For a systematic search for the molecular outflows in the VeLLOs, we selected the 62 samples from our new catalog by M. Kim et al. giving the most complete collection of the VeLLO candidates in nearly all molecular clouds of Gould Belt regions. We carried out pointing observations for them in CO (2-1) and/or CO (3-2) molecular lines using the SRAO, CSO, or ASTE radio single-dish telescopes. We then made mapping observations for 29 VeLLOs with the same molecular lines. In this workshop, we present the preliminary results of our search for molecular outflows toward these sources. 29 VeLLOs were mapped in either CO (2-1), 13CO (2-1), and C18O (2-1) or CO (3-2), 13CO (3-2), and C18O (3-2) molecular lines. From these observations, we found 6 new VeLLOs having a bipolar outflow. We derived their physical properties such as outflow mass, force, accretion rate, and so on. They have the sub-parsec size (0.03-0.6 pc) lobe of molecular outflow and the small mass accretion rate of (0.1-10.9)x10-7 M? yr-1. From these properties, we will discuss their present status and future fate with their envelop mass and internal luminosity. Author(s): Gwanjeong Kim1, 2, Chang Won Lee1, Miryang Kim1, 3, Kiyokane Kazuhiro4, 5, Masao Saito4 Institution(s): 1. Korea Astronomy and Space Science Institute, Daejeon, Korea, Republic of. 2. University of Science and Technology, Daejeon, Korea, Republic of. 3. Chungbuk National University, Cheongju, Korea, Republic of. 4. National Astronomical Observatory of Japan, Tokyo , Japan. 5. University of Tokyo, Tokyo, Japan.

108.12 – Chemical Differentiation of CS and N2H+ in Dense Starless Cores CS molecule as an important tracer for studying inward motions in dense cores is known to be adsorbed onto dusts in cold (T~10K) dense cores, resulting in its significant depletion in the central region of the cores which may hamper a proper study of kinematics stage of star formation. However, the chemical behavior of this molecule still seems under questions because of a paucity of the cases showing the CS depletion in dense cores. In this study we choose five ‘evolved’ dense starless cores, L1544, L1552, L1689B, L694-2 and L1197, to investigate how depletion of CS molecule is significant and how the molecule differentiates depending on the evolutional status of the dense cores, by using a rare isotopomer C34S. We performed mapping observations in C34S(J=2-1) and N2H+(J=1-0) with Nobeyama 45-m telescope. We compared the intensity maps of two molecular lines with 850?m continuum data as a reference of the density distribution of the dense cores, finding that CS molecules are centrally depleted in all of our targets and seen as ‘semi-ring-like’ holes in its distribution, while N2H+ shows a central peak distribution as the one in dust continuum. This is also seen in the abundance radial profiles of two molecules for all of our targets where the CS abundance decreases toward the core center while the N2H+ keeps abundant constantly. Our data confirm the claim that CS molecule generally depletes out in the central region in starless cores, while N2H+ keeps abundant as they get evolved. The quantitative analysis on CS depletion in the dense cores, for example, the size of CS depletion area and radial (or gas density) dependence of CS depletion, is presented in the conference. Author(s): Shinyoung Kim1, Chang Won Lee2, 3, Jungjoo Sohn1, Gwanjeong Kim2, 3, Mi-Ryang Kim2, 4 Institution(s): 1. Korea National University of Education, Chungbuk, Korea, Republic of. 2. Korea Astronomy and Space Science Institute, Daejeon, Korea, Republic of. 3. University of Science and Technology, Daejeon, Korea, Republic of. 4. Chungbuk National University, Cheongju, Korea, Republic of. 108.13 – Formation of Magnetized Prestellar Cores with Ambipolar Diffusion and Turbulence We investigate the roles of magnetic fields and ambipolar diffusion during prestellar core formation in turbulent giant molecular clouds (GMCs), using three-dimensional numerical simulations. Our simulations focus on the shocked layer produced by a converging flow within a GMC, and survey varying ionization and angle between the upstream flow and magnetic field. We also include ideal magnetohydrodynamic (MHD) and hydrodynamic models. From our simulations, we identify hundreds of self-gravitating cores that form within 1 Myr, with masses M~0.04-2.5 solar-mass and sizes L~0.015-0.07 pc, consistent with observations of the peak of the core mass function (CMF). Median values are M=0.47 solar-mass and L=0.03 pc. Core masses and sizes do not depend on either the ionization or upstream magnetic field direction. In contrast, the mass-to-magnetic flux ratio does increase with lower ionization, from twice to four times the critical value. The higher mass-to-flux ratio for low ionization is the result of enhanced transient ambipolar diffusion when the shocked layer first forms. However, ambipolar diffusion is not necessary to form low-mass supercritical cores. For ideal MHD, we find similar masses to other cases. These masses are 1-2 orders of magnitude lower than the value that defines a magnetically supercritical sphere under post-shock ambient conditions. This discrepancy is the result of anisotropic contraction along field lines, which is clearly evident

in both ideal MHD and diffusive simulations. We interpret our numerical findings using a simple scaling argument which suggests that gravitationally critical core masses will depend on the sound speed and mean turbulent pressure in a cloud, regardless of magnetic effects. Author(s): Che-Yu Chen1, Eve Ostriker2 Institution(s): 1. University of Maryland, College Park, MD. 2. Princeton University, Princeton, NJ. 200 – Plenary: The Theory of Dense Core Collapse Plenary Session – Grove – 29 Jul 2014 09:00 am to 09:45 am Chair(s): Mario Tafalla 200.01 – The Theory of Dense Core Collapse I will review the theory of dense core collapse, with an emphasis on disk formation. Disk formation, once thought to be a simple consequence of the conservation of angular momentum during hydrodynamic core collapse, is far more subtle in magnetized gas. In this case, rotation can be strongly magnetically braked. Indeed, both analytic arguments and numerical simulations have shown that disk formation is suppressed in ideal MHD at the observed level of core magnetization. I will discuss the physical reason for this so-called “magnetic braking catastrophe,” and review possible resolutions to the problem that have been proposed so far, including non-ideal MHD effects, misalignment between the magnetic field and rotation axis, and turbulence. Other aspects of core collapse, such as fragmentation and outflow generation, will also be discussed. Author(s): Zhi-Yun Li1 Institution(s): 1. UC, Berkeley, Berkeley, CA. 201 – Plenary: Identification of Super-Jeans Mass Cores Plenary Session – Grove – 29 Jul 2014 09:45 am to 10:30 am Chair(s): Mario Tafalla 201.01 – Identification of Super-Jeans Mass Cores Pre-stellar cores are starless cores that are gravitationally bound and hence likely to collapse into protostars. Observationally identifying examples of such cores as bound can be tricky, however, given the uncertainties involved in the opacities, dust-to-gas ratios, temperatures, and distances of cores. Nevertheless, some starless cores are seen to be "super-Jeans," i.e., more massive than its thermal Jeans mass, suggesting they may collapse or fragment into protostars. (Of course, this occurrence depends on other forms of non-thermal support.) We present evidence for several super-Jeans mass cores identified by SCUBA observations, and describe the prospects for identifying more examples from the JCMT and Herschel Gould Belt Surveys. Such cores may have interesting kinematics even prior to collapse. For example, recent JCMT observations of a selection of pre-stellar cores show either inward or outward motions. In addition, we also describe one super-Jeans starless core, L1689-SMM16, that appears to be experiencing oscillations. Indeed, oscillations may be seen in cores that are significantly super-Jeans, as compression waves pass from warm exteriors to cold interiors.

Author(s): James Di Francesco1 Institution(s): 1. Herzberg Inst. of Astrophysics, Victoria, BC, Canada. 202 – Plenary: Inward Motions in Dense Molecular Cores Plenary Session – Grove – 29 Jul 2014 11:00 am to 11:45 am Chair(s): Mario Tafalla 202.01 – Inward Motions in Dense Molecular Cores I will review our molecular line searches for inward motion in starless dense cores. Conducted over ten years, these studies have found such motions to be prevalent in these objects. I will discuss the statistics of this internal motion, and its relationship to core density and evolution. Blue asymmetric profiles are dominant, indicating that inward motions are prevalent. These blue profiles are more common, and their asymmetry is bluer, at core positions with higher N2H+ line emission or higher column density. Based on their molecular line maps, starless cores can be classified into four different types: contracting, oscillating, expanding, and static. Contracting cores have the highest column density, greater than 6 x 10^21 cm-2, while static cores have the lowest. Our classification may indicate an evolutionary progression: static cores in the earliest stage, expanding and/or oscillating cores in the next, and contracting cores in the final stage. Author(s): Chang Won Lee1 Institution(s): 1. Korea Astronomy & Space Science Institute, Yuseong-gu, Daejeon, Korea, Republic of. 203 – Tuesday Session 1 Oral Session – Grove – 29 Jul 2014 11:45 am to 12:05 pm Chair(s): Mario Tafalla 203.01 – Mid-infrared Variability and Mass Accretion Toward NGC 2264 Protostars Variable mass accretion has been suggested to be an important aspect of protostar formation. Mid-infrared wavelength observations trace variations in accretion luminosity and thus can probe mass accretion on sub-AU scales. We present results from the Spitzer YSOVAR campaign towards class I protostars in NGC 2264. The precise (0.02 mag) several hour cadence light curves at 3.6 and 4.5 microns show that young star variability is ubiquitous, with a variety of morphologies and time scales. A structure function analysis shows the light curves, on average, have a power-law behavior up to 30 days. Moreover, the average structure function is the same for protostars in NGC 2264 and Orion. The power-law behavior suggests a stochastic process such as turbulent mass accretion. We discuss theoretical models and the prospects for determining mass accretion rates from synoptic studies. Author(s): Susan Terebey1, Ann Marie Cody2, Luisa M. Rebull2, John R. Stauffer2 Institution(s): 1. Cal. State Univ. at Los Angeles, Los Angeles, CA. 2. Caltech, Pasadena, CA. Contributing team(s): YSOVAR Science Team, CSI2264 Science Team

204 – Plenary: The First ALMA View of IRAS 16293-2422: Infall and Rotation Plenary Session – Grove – 29 Jul 2014 01:35 pm to 02:20 pm Chair(s): Mario Tafalla 204.01 – The First ALMA View of IRAS 16293-2422: Infall and Rotation The collapse of a dense core is a crucial step in understanding the formation of a star. There have been several claims for the observation of infall onto a protostar, however, it has never been free of controversy. Here we present ALMA Science Verification observations IRAS 16293-2422 proto-binary that allow us to study the kinematic of the gas close to the protostar. Thanks to the great sensitivity and image quality obtained with ALMA, we identify an inverse P-Cygni profile towards IRAS16293 B on complex organic molecules which provide the first incontrovertible detection of infall towards a protostar. We model the profile and estimate an infall rate of 4.5 x 10^-5 Msun/year. With the same observations we study the rotation towards IRAS16293 A, which display a position-velocity diagram consistent with pure rotation around a central mass of 0.53 Msun, but no evidence for infall could be identified. Finally, I will discuss the future prospects of using ALMA to study the infall around protostars. Author(s): Jaime E. Pineda1 Institution(s): 1. University of Manchester, UK, Manchester, Lancashire, UK, United Kingdom. 205 – Plenary: The Role of Environment in the Formation of Low Mass Stars: Lessons from the Orion Molecular Clouds Plenary Session – Grove – 29 Jul 2014 02:20 pm to 03:05 pm Chair(s): Mario Tafalla 205.01 – The Role of Environment in the Formation of Low Mass Stars: Lessons from the Orion Molecular Clouds Low mass stars form in diverse environmental conditions, and understanding how these conditions influence the fragmentation and collapse of the molecular gas into stars is of key interest. The Orion molecular clouds are a remarkable laboratory for studying low mass star formation across the full range of environments, from crowded clusters containing massive stars, to moderate sized groups ofintermediate and low mass stars, and finally to relatively isolated low mass star formation. We present results from the Herschel Orion Protostar Survey, or HOPS, a study of over 300 protostar in the Orionclouds with the Herschel, Spitzer, Hubble and APEX telescopes. These data provide the means to identify young stars and protostars, determine the properties of the protostars, and map the column density of the dense gas in their surroundings. We examine how the properties of the protostars depend on the local environment, as traced by the surface densities of YSOs and gas, and we discuss the implications for our understanding of low mass star formation. Author(s): S. Thomas Megeath1 Institution(s): 1. Univ. Of Toledo, Toledo, OH.

206 – Tuesday Session 2 Oral Session – Grove – 29 Jul 2014 03:05 pm to 03:45 pm Chair(s): Mario Tafalla 206.01 – The VLA Perseus Protostar Survey: Class 0/I Disks and Multiplicity We present results to-date of the Jansky VLA Perseus young protostellar disk and multiplicity survey of all known Class 0 and I protostars in the Perseus molecular cloud (d~230 pc). The ~80 protostars are observed at at 8 mm, 1 cm, 4 cm and 6.6 cm, sensitive to both dust and free-free emission from the protostars. The survey consists of A and B configuration observations, resolving features as small as ~0.06'' while remaining sensitive to ~4'' structures. The 15 AU spatial resolution is capable of detecting close binaries and samples completely the peak of the protostellar field binary separation distribution (~50 AU) for the first time, which is a possible bimodal distribution, and we have already detected 16 previously unknown close binaries. We are able to resolve disks as small as R~15 AU and have so far resolved 6 candidate disks with R>20 AU. We have also detected 3 candidate circumbinary disks, one of which displays prominent extended circumbinary emission that is possibly a fragmenting circumbinary disk--a theorized mechanism for binary formation. This is the largest and most complete millimeter/centimeter high-resolution survey of protostellar disks and binaries. The results of the binary separation distribution and multiplicity frequency will significantly improve our understanding of earliest stages of binary formation. The survey has already doubled the number of known Class 0 disk candidates and will lead to further understanding of the prevalence of close binaries and disks at early times as observations continue. Author(s): Dominique Segura-Cox1, Leslie Looney1, John Tobin2, Zhi-Yun Li3, Claire Chandler4, Mike Dunham5, Sarah Sadavoy6, Carl Melis7, Kaitlin Kratter8, Laura Perez4, Robert Harris1 Institution(s): 1. University of Illinois, Urbana, IL. 2. NRAO, Charlottesville, VA. 3. University of Virginia, Charlottesville, VA. 4. NRAO, Socorro, NM. 5. CfA, Cambridge, MA. 6. MPIA, Heidelberg, Germany. 7. University of San Diego, San Diego, CA. 8. University of Arizona, Tucson, AZ. 206.02 – Detection of a Magnetized Disk around a Very Young Protostar We present subarcsecond resolution polarimetric observations of the 878 ?m thermal dust continuum emission obtained with the Submillimeter Array toward the IRAS 16293-2422 protostellar binary system. We report the detection of linearly polarized dust emission arising from the circumstellar disk associated with the IRAS 16293-2422 B protostar. The fractional polarization of ~= 1.4% is only slightly lower than that expected from theoretical calculations in such disks. The magnetic field structure on the plane of the sky derived from the dust polarization suggests a complex magnetic field geometry in the disk, possibly associated with a rotating disk that is wrapping the field lines as expected from the simulations. The polarization around IRAS 16293-2422 A at subarcsecond angular resolution is only marginally detected. Author(s): Ramprasad Rao1, Josep Miquel Girart2, Shih Ping Lai3, Dianiel P. Marrone4 Institution(s): 1. Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), Hilo, HI. 2. IEEC CSIC, Barcelona, Catalonia, Spain. 3. NTHU, Hsinchu, Taiwan. 4. University of Arizona, Tucson, AZ.

207 – Tuesday Session 3 Oral Session – Grove – 29 Jul 2014 04:00 pm to 06:00 pm Chair(s): Mario Tafalla 207.01 – Bridging the Gap between Large-Scale Simulations and Observations of Star Forming Cores Numerical simulations and observations of star forming cores are topics that both see a lot of progress these years. MHD simulations of molecular clouds have reached a level, where it is possible to evolve the cloud on parsec scale, while simultaneously resolving the neighbourhood around the individual protostars on AU scale. At the same time interferometers such as ALMA, with its increased sensitivity and resolving capabilities, are making it possible to zoom in on the protostellar cores in their earliest stages and map their gas and dust content. The advances in simulations and observations also open the possibility of comparing the two directly. I will present synthetic observations of a large number of protostellar cores, created from the high resolution numerical simulations of Haugbølle, Padoan and Nordlund in prep (see Padoan et al 2012 for similar lower resolution models). The synthetic observations are compared directly to real observations obtained from a range of different submm telescopes. The motivation for comparing real and synthetic observations is twofold. It enables us to test the validity of the simulations by ensuring that the synthetic observations agree with the real ones, and in the cases where they differ to identify the issues. In addition to this, through the simulations we are able to gain additional insight into the physics behind the observations. I will present several cases where synthetic and real observations have been compared. In one example of this we used 24 ?m Spitzer maps, and 850 ?m SCUBA maps from Perseus and Ophiuchus to calculate the distribution of distances between protostars and their parental cores (Jørgensen et. al. 2007, 2008). Both real and synthetic observations produce a centrally peaked distribution (HWHM smaller than the typical core radius). This indicates that on average newly formed protostars do not migrate far away from their parental core. Author(s): Søren Frimann1, 2, Jes Kristian Jørgensen1, 2, Troels Haugbølle2, 1 Institution(s): 1. Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark. 2. Centre for Star and Planet Formation, University of Copenhagen, Copenhagen, Denmark. 207.02 – Evidence of Feedback? A Correlation Between Class 0 Protostars and the Dense Gas Distribution in the Perseus Molecular Cloud Class 0 protostars are an early, deeply embedded stage of star formation. Additionally, Class 0 protostars are thought to be relatively short-lived, and thus, they represent well the instantaneous star formation activity in their parent cloud. Here, we present a catalogue of 28 Class 0 protostars for the Perseus molecular cloud identified using Herschel observations from the Gould Belt Survey and archival Spitzer catalogues of young stellar objects (YSOs). We compare the instances of Class 0 sources in seven different clumps in Perseus, and determined that those clumps with broader column density distributions have higher fractions of Class 0 protostars and higher instantaneous star formation efficiencies. These correlations suggest that the quantity of high column density material in a clump relates to the age of its YSO population. We propose that feedback from either the formation of YSOs or their evolution alters the

ambient (column) density structure, producing lower fractions of high column density material and thereby slowing the formation of additional Class 0 protostars. Author(s): Sarah Sadavoy1, James Di Francesco2, Philippe Andre3, Stefano Pezzuto4 Institution(s): 1. Max Planck Institute for Astronomy, Heidelberg, Germany. 2. NRC, Victoria, BC, Canada. 3. CEA, Saclay, France. 4. IAPS, Rome, Italy. Contributing team(s): Herschel Gould Belt Survey 207.03 – Shocked and Scorched - Free-Floating Evaporating Gas Globules and StarFormation Massive stars have a strong feedback effect on their environment, via their winds, UV radiation, and ultimately, supernova blast waves, all of which can alter the likelihood for the formation of stars in nearby clouds and limit the accretion process of nearby protostars. Free-floating Evaporating Gaseous Globules, or frEGGs, are a newly recognized class of stellar nurseries embedded within the giant HII regions found in massive star-formation region (MSFRs). We recently discovered the prototype frEGG in the Cygnus MSFR with HST. Further investigation using the Spitzer and Herschel archives have revealed a much larger number (>50) in Cygnus and other MSFRs. Our molecular-line observations of these show the presence of dense clouds with total masses of cool molecular gas exceeding 0.5 to a few Msun associated with these objects, thereby disproving the initial hypothesis based on their morphology that these have an origin similar to the proplyds (cometary-shaped photoevaporating protoplanetary disks) found in Orion. We report the results of our molecular-line studies and detailed high-resolution optical (with HST) or near-IR (with AO at the Keck Observatory) imaging of a few frEGGs in Cygnus, Carina and the W5 MSFRs. The images show the presence of young stars with associated outflow cavities and/or jets in the heads of the tadpole-shaped frEGGs. These results support our hypothesis that frEGGs are density concentrations originating in giant molecular clouds, that, when subject to the compression by the strong winds and ionization from massive stars in these MSFRs, become active star-forming cores. In summary, by virtue of their distinct, isolated morphologies, frEGGs offer us a clean probe of triggered star formation on small scales in the vicinity of massive stars. Author(s): Raghvendra Sahai1, Mark Morris2, Mark Claussen3 Institution(s): 1. JPL, Pasadena, CA. 2. UCLA, Los Angeles, CA. 3. NRAO, Socorro, NM. 207.04 – Study of Outflow and Molecular Lines from the Observations of BHR71 by The Herschel Key Program,``Dust, Ice, and Gas In Time" (DIGIT) The infall and outflow processes initiated by the collapse a dense core are widely observed in Class 0 protostars, and significantly change the density and temperature structure of the prestellar core as well as the following disk and envelope evolution. Since the Class 0 protostars are usually embedded in the cold molecular envelope preventing them from being observed at visible or near-IR wavelengths, the spectral analyses of the far-IR spectra provide us a window to look through the envelope and constrain the physical properties of the envelope and the core. BHR71, a Class 0 embedded protostar, is located in an isolated neighborhood with a collimated bipolar outflow and shows a rich far-IR spectrum as observed in the DIGIT program (PI: Neal Evans) with Herschel. It has numerous molecular and atomic features that can constrain its physical properties and the density structure well. In this research, we developed a

robust data reduction (Green et al. 2013a, b) and automatic line fitting package that ensures all of the molecular and atomic lines are extracted to the same standard and it can be easily used for any other protostars observed by Herschel as well. We found 44 and 28 emission lines in the central spaxel in the PACS and the SPIRE bands respectively, including CO, 13CO, OH, and H2O. The extended feature observed at low-J CO and several H2O lines are consistent to the outflow direction but less collimated and a heterogeneous environment is concluded from the rotational diagram analysis. A dust Monte Carlo radiative transfer simulation using RADMC-3D will reveal the embedded structure with a dust density profile of a flared disk and a spherical envelope with bipolar outflow cavity. We will use a line radiative transfer simulation for multiple species to constrain the chemical abundance distributions and their temperature profiles.With high sensitivity spatial resolved spectra and simulated internal structure analysis of BHR71 will provide a good test of theoretical models of the infall and outflow. Author(s): Yao-Lun Yang1, Joel D. Green1, Neal J. Evans1 Institution(s): 1. University of Texas at Austin, Austin, TX. Contributing team(s): DIGIT Team 207.05 – Using Spinning Dust Emission To Constrain The Abundance Of Small Dust Grains In Dense Cores Dense cores within molecular clouds represent a crucial step in the life cycle of dust as it evolves from the diffuse to the dense media, however, the size distribution of dust grains in these environments is still uncertain. In this analysis we constrain the abundance of small dust grains in dense cores using observations of spinning dust emission. If small dust grains are present in these cores, then even though stellar photons cannot penetrate deep enough to excite them to emit at mid-IR wavelengths, the small dust grains will be spun-up by collisions and emit spinning dust radiation. Therefore spinning dust emission can be used as a direct probe of the small dust grains in these cores. With this in mind, we present the first attempt to observe spinning dust emission in molecular cores and use it to constrain the abundance of the small dust grains, and hence help to determine the evolution of dust within these dense environments. Author(s): Christopher T. Tibbs1, Roberta Paladini1, Kieran Cleary1, Keith Grainge2, Stephen Muchovej1, Tim Pearson1, Yvette Perrott3, Anthony Readhead1, Clare Rumsey3, Anna Scaife4, Matthew Stevenson1, Jackie Villadsen1 Institution(s): 1. California Institute Of Technology, Pasadena, CA. 2. University Of Manchester, Manchester, United Kingdom. 3. University Of Cambridge, Cambridge, United Kingdom. 4. University Of Southampton, Southampton, United Kingdom. 300 – Plenary: Modeling Massive Star Formation Plenary Session – Grove – 30 Jul 2014 09:00 am to 09:45 am Chair(s): Gary Fuller (University of Manchester) 300.01 – Modeling Massive Star Formation In this contribution I will discuss how massive star forming cores might compare to their lower mass brethren using insights from theoretical models. Is there such a thing as a truly massive

pre-stellar core? Do massive star forming cores grow in mass, or is the core mass fixed when a protostar is formed? What is the role of filaments in forming massive protostellar cores? After I have discussed these theoretical considerations I will then examine how such questions can be tested by observations. Author(s): Rowan Smith1 Institution(s): 1. Institut für Theoretische Astrophysik, Heidelberg, Germany. 301 – Plenary: Infrared Dark Clouds: Cloud Dynamics and Core Formation Plenary Session – Grove – 30 Jul 2014 09:45 am to 10:30 am Chair(s): Gary Fuller (University of Manchester) 301.01 – Infrared Dark Clouds: Cloud Dynamics and Core Formation In the past ten years, Infrared Dark Clouds (IRDCs) have received considerable attention. The darkness of these clouds ensures that little protostellar feedback has managed to disturb the initial conditions for star formation. IRDCs are ideal targets to study the earliest stages of star formation. In this talk I will review recent progress which has been made on our understanding of IRDC fragmentation and core formation. I will focus my talk on IRDC core properties, and will question the role of cloud dynamics on the mass determination of star forming cores. I will further argue that large-scale cloud collapse is a key stage of massive star formation, and discuss its implications on a universal star formation process. Author(s): Nicolas Peretto1 Institution(s): 1. Cardiff University, Cardiff, Wales, United Kingdom. 302 – Plenary: Fragmentation of Molecular Clumps and Formation of Massive Cores Plenary Session – Grove – 30 Jul 2014 11:00 am to 11:45 am Chair(s): Gary Fuller (University of Manchester) 302.01 – Fragmentation of Molecular Clumps and Formation of Massive Cores Massive protostars are born in parsec-scale molecular clumps that collapse and fragment, leading to the formation of a cluster of stellar objects. The interplay among gravity, turbulence and magnetic fields affects the outcome of fragmentation. The physical condition (temperature and density) in molecular clumps limits the Jeans mass to about 1 Msun. This creates a theoretical puzzle for massive star formation since dense cores much larger than 1 Msun tend to further fragment into lower mass entities. In this talk, I will present recent high resolution observations of massive molecular clumps at very early evolutionary stages. I will discuss fragmentation, physical and chemical evolution of molecular coresand the implication of these findings to current theoretical ideas of massive star and cluster formation. I will also present measurements of dust polarization of a large sample of massive molecular clumps, which suggest that magnetic fields play an important role during the collapse of molecular clumps and the formation of dense cores. Author(s): Qizhou Zhang1 Institution(s): 1. Harvard-Smithsonian, CfA, Cambridge, MA.

303 – Wednesday Session 1 Oral Session – Grove – 30 Jul 2014 11:45 am to 12:05 pm Chair(s): Gary Fuller (University of Manchester) 303.01 – Physical and Chemical Properties of Massive Starless Cores in Infrared Dark Clouds Massive starless cores are the initial conditions of massive stars in some theories of massive star formation, so it is important to identify and characterize such objects. I summarize our group’s efforts to find massive starless cores in Infrared Dark Clouds (IRDCs), using MIR and FIR extinction mapping together with molecular line follow-up, especially of deuterated species with ALMA. Several candidates have been identified, including examples with masses up to about 60 solar masses. I discuss the dynamical state of the cores, including implications for magnetic field strengths. By modeling the chemical evolution of the cores, especially the rise in the level of deuteration of certain species, we are also able to constrain chemical ages and rates of collapse. Author(s): Jonathan Tan1 Institution(s): 1. University of Florida, Gainesville, FL. 304 – Plenary: Formation of Massive Clusters in the Galactic Center: Theory and Observations Plenary Session – Grove – 30 Jul 2014 01:35 pm to 02:20 pm Chair(s): Gary Fuller (University of Manchester) 304.01 – Formation of Massive Clusters in the Galactic Center: Theory and Observations The ultimate goal of star formation studies is an end-to-end understanding of stellar mass assembly as a function of environment. Existing observations have two fundamental limitations to reaching this goal: they predominantly focus on regions with similar environmental conditions, and observations of a region can only provide a single evolutionary snapshot. In this talk I will discuss a way we may be able to overcome both these problems by exploiting a causally-related system of clouds in the extreme environment of the Galactic Center. Specifically, I will present results from both observational and numerical simulation studies testing whether star formation has been triggered in these clouds by close passage to the bottom of the Galactic gravitational potential, at the location of the supermassive black hole, Sgr A*. If the scenario can be confirmed, this system of gas clouds will provide a laboratory for studying stellar mass assembly as a function of ABSOLUTE time, allowing us to: (i) directly test theoretical predictions of molecular cloud structure evolution in turbulent clouds; (ii) unambiguously determine how postulated critical density thresholds for star formation vary with environment; (iii) follow the mass assembly of gravitationally bound cores, including likely precursors to stars >100 Msun, thereby directly testing SF theories at the most extreme mass ranges. Author(s): Steve Longmore1 Institution(s): 1. Liverpool John Moores University, Liverpool, England, United Kingdom.

305 – Plenary: Clumps & Cores in Massive Star-Forming Regions from Orion to the Central Molecular Zone Plenary Session – Grove – 30 Jul 2014 02:20 pm to 03:05 pm Chair(s): Gary Fuller (University of Manchester) 305.01 – Clumps & Cores in Massive Star-Forming Regions from Orion to the Central Molecular Zone I will present Bolocam, Herschel Hi-GAL, and ALMA results on selected massive star and star cluster-forming clumps. While the Central Molecular Zone (CMZ) contains many dense and compact clumps sufficiently massive to form young massive clusters (YMCs) such as the Arches, it is unclear if the best studied example, G0.25+0.02 (a.k.a the "Brick") will actually do so. In the Galactic disk no "pre-stellar" clumps with sufficient mass to form a YMC have yet been found. Thus, in cluster formation, the equivalent of a "pre-stellar" core may be rare. All detected clumps sufficiently massive to form a YMC are already forming massive stars. In the Galactic disk, YMCs may be assembled by the merger of sub-clusters dragged-in by converging gas flows. Author(s): John Bally1 Institution(s): 1. Univ. of Colorado, Boulder, CO. 306 – Wednesday Session 2 Oral Session – Grove – 30 Jul 2014 03:05 pm to 03:45 pm Chair(s): Gary Fuller (University of Manchester) 306.01 – CN Zeeman Mapping of Magnetic Fields in Dense Molecular Cores The many possible roles of magnetic fields in star formation remain unclear, requiring observations of magnetic fields at all stages and conditions to further our understanding. Zeeman observations provide the only direct measurement of magnetic field strengths in molecular clouds and cores, and maps provide information about field structure. Of the Zeeman-sensitive species, CN offers the best opportunity to sample the higher density gas in molecular cores and their envelopes. Earlier single-dish CN Zeeman N=1-0 measurements were with 23" resolution; needed next are higher angular resolution CN Zeeman maps in order to explore magnetic field strengths and morphologies in dense cores and their envelopes. Here I report CARMA Zeeman-effect mapping of the N=2-1 CN transitions with ~3" resolution toward W3OH and DR21OH, both high-mass star formation regions that have previous single-dish Zeeman detections at 23” resolution. Toward W3OH the line-of-sight field strength reaches 4 mG (4 times higher than the single-dish result) with clear spatial structure. The analysis of DR21OH results will be completed by the meeting and presented also. These are the first interferometric CN Zeeman observations and detections of dense molecular cores. I discuss the implications for the role of magnetic fields in the formation and evolution of dense cores and the possibilities for future ALMA Zeeman work. Author(s): Richard Crutcher1 Institution(s): 1. Univ. of Illinois, Urbana, IL.

307 – Wednesday Session 3 Oral Session – Grove – 30 Jul 2014 04:00 pm to 06:00 pm Chair(s): Gary Fuller (University of Manchester) 307.01 – The high-mass star-forming core G35.2N: what have we learnt from SOFIA and ALMA observations? G35.2N is a luminouos, star forming core in a filamentary cloud at a distance of 2.2 kpc. It is associated with a thermal N-S radio jet and a misaligned NE-SW CO outflow observed both with SOFIA FORCAST (30 and 40 microns, ~4" resolution; Zhang, Tan, de Buizer et al. 2013) and with ALMA band 7 (850 micron line and continuum, 0.4" resolution; Sanchez-Monge, Cesaroni, Beltran et al. 2013, 2014). The ALMA observations revealed a NW-SE Keplerian rotating disk in the CH3CN molecule (Sanchez-Monge et al.) with an enclosed protostellar mass of 18 +/- 3 Mo, whose orientation is inconsistent with the N-S radio jet, and whose protostellar mass is marginally inconsistent with the one inferred from the SED modelling (20-34 Mo, L ~ 10(5) Lo; Zhang et al.) We review the various assumptions involved in the derivation of the disk interpretation and the SED modelling. The dynamical mass could be in the form of a close binary (two 9 Mo stars, say) in which case the predicted total luminosity would be 3 x 10(4) Lo, close to the actually observed one (as opposed to the modelled one, which takes into account the flashlight effect and unmeasured radiation that escapes along a bipolar cavity). One the other hand, if the inferred higher-luminosity model is correct, the disk interpretation of ALMA rotation curve may have to be challenged, and what seems like a nice disk might be a more complex dynamical structure, such as a warped or precessing disk around a binary protostar or a different (outflow-related) velocity-structure altogether. These observations show the complexity of the interpretation of multi-wavelength observations of high-mass star forming regions when viewed with different spatial resolutions. Author(s): Hans Zinnecker1, Goeran Sandell1 Institution(s): 1. NASA - Ames Research Center, Moffett Field, CA. 307.02 – Physical Conditions and Star Formation in Cluster-Forming Molecular Clumps The CHaMP project has identified a uniform sample of 303 massive (20-8000 M ?), dense (200-30,000 cm-3) molecular clumps in a large sector of the southern Milky Way that includes much of the Carina Arm. These are the kinds of clumps that are likely to be the precursors to IRDCs, large stellar clusters, and massive stars. We report new IR and mm-wave results of the physical conditions in these clouds and their star formation activity. These include a correlation between several molecular tracers and the ionising output from embedded MYSOs, and widespread spatial variability in several line ratios. An analysis of the HCN emission further reveals that the physical conditions in the gas (i.e., the excitation temperature, optical depth, and column density) do not follow the molecular line emissivity in a straightforward way. This has important consequences for the interpretation of wider correlations, such as the Kennicutt-Schmidt and/or Larson's relations. Such relations may have hidden biases that depend on the spatial variation in physical conditions illustrated by our results. Author(s): Peter J. Barnes1, William J. Schap1, Adam G. Ginsburg2, Tony Ordonez1 Institution(s): 1. University of Florida, Gainesville, FL. 2. ESO, Garching, Bavaria, Germany.

307.03 – SMA and VLA Observations of Dense Cores at Different Evolutionary Phases in Filamentary IRDCs Infrared dark clouds (IRDCs) are recognized as nurseries of high-mass stars in the Galaxy given that they are massive, dense, and cold. High angular resolution millimeter/sub-millimeter observations are necessary to penetrate the dense gas and resolve the embedded cores in these clouds. With the SMA, we selected four dense molecular clumps probably at quite different evolutionary phases in the IRDC G28.53-0.25, and obtained their dust emission and molecular spectral lines. We identified six dense cores. Those at very early phases exhibit few spectral lines, while those that are more evolved exhibit complex organic molecular lines as well as signature of outflows. Both types of cores are massive enough (a few tens of solar mass) to form high-mass (>8 Msun) stars. VLA ammonia spectral lines were also obtained, to constrain optical depth, temperature, and gas kinematics. Furthermore, we selected four filamentary IRDCs from our VLA ammonia survey of high-mass star forming regions, and conducted a mini survey with the SMA in order to study the relation between filaments and high-mass star formation. We found star forming cores in the intersection of filaments, as well as cores embedded in filaments that show little star formation signatures. Author(s): Xing Lu1, 2, Qizhou Zhang1, Hauyu B. Liu3 Institution(s): 1. Harvard-Smithsonian CfA, Cambridge, MA. 2. School of Astronomy and Space Science, Nanjing University, Nanjing, Jiangsu, China. 3. Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan. 307.04 – Hot Ammonia in the Densest Massive Cores Hot molecular cores are believed to be the birthplace of high-mass (O-B type) stars. Their formation process is however still a matter of debate, chiefly owing to the lack of observational evidence of accreting O-type young stars. In this context, imaging of optically-thin, highly-excited molecular lines at cm-wavelengths provide the best tool for probing the hottest and densest gas at small radii from O-type forming stars, i.e. in centrifugally-supported disks and/or infalling envelopes, whose innermost regions can be inaccessible even to (sub)mm interferometry because of large optical depth of dust emission. In particular, ammonia is an excellent "thermometer" of dense molecular gas and it can trace excitation up to temperatures of 2000 K by observing its inversion transitions within a relatively narrow frequency range, 20-40 GHz, which are sensitive to gas of different temperatures and densities. I will report initial results from an imaging survey of hot-cores in the Galaxy in the ammonia lines from (6,6) up to (14,14) with the JVLA. Towards NGC7538 IRS1 and W51, the multi-transition data sets enabled us to identify the densest massive hot cores known and to probe kinematics of rotating disks and infalling envelopes around O-type young stars. Author(s): Ciriaco Goddi1, Qizhou Zhang2 Institution(s): 1. JIVE, Dwingeloo, Netherlands. 2. CfA, Cambridge, MA. 307.05 – Issues with SED fitting, PMS tracks, and the birthline exemplified with two cores near IRAS 05345+3157 SED fitting is a powerful tool to characterize dense cores and the SED models by Robitaille et al. make it easy to find a good fit. However, the interpretation of the results is far from straight

forward as I will demonstrate using two intermediate-mass cores near IRAS 05345+3157. I will discuss the SED fitting and a method to analyse biases introduced by the model grid and some degeneracies in the parameter space. At that point, one has the detailed parameters for the central source and the envelope. However, the radius for the central sources of the core in IRAS 05345+3157 are larger than any protostar should be. The problem is that the central sources of the SED models were populated from pre-main sequence (PMS) tracks including the unphysical portion above the birthline. Another unphysical situation might arise from models having an accretion disk but the central sources are picked from by definition non-accreting PMS tracks. We are trying to correct the SED fitting result for these issues. Author(s): Randolf Klein1 Institution(s): 1. USRA-SOFIA, Moffett Field, CA.

Authors Index

Andre, Philippe 100.01 Arce, Hector G 108.08 Arce, Hector 107.01 Bally, John 305.01 Barnes, Peter John 307.02 Battersby, Cara 306.02 Booker, Joseph J. 108.07 Boss, Alan P. 108.01 Bourke, Tyler L. 104.01 Carey, Sean J 108.04 Chen, Che-Yu 108.13 Cimorelli, Salvatore 108.02 Cody, Ann Marie 203.01 Crutcher, Richard 306.01 Di Francesco, James 201.01 Di Francesco, James 207.02 Favre, Cécile 108.09 Forbrich, Jan 107.04 Friesen, Rachel 102.01 Frimann, Søren 207.01 Girart, Josep Miquel 206.02 Goddi, Ciriaco 307.04 Green, Joel D 207.04 Hacar, Alvaro 103.01 Hennebelle, Patrick 107.03 Jørgensen, Jes Kristian 207.01 Keiser, Sandra A 108.01 Kim, Gwanjeong 108.11 Kim, Mi-Ryang 108.10 Kim, Shinyoung 108.12 Kirk, Helen 101.01 Klein, Randolf 307.05 Klein, Richard I. 106.02 Lee, Chang Won 108.10, 108.11, 108.12 Li, Pak Shing 106.02 Li, Zhi-Yun 200.01 Lim, Wanggi 108.04 Longmore, Steve 304.01 Looney, Leslie 206.01 Lu, Xing 307.03 Lykke, Julie M 108.09 Maureira, Maria Jose 108.08

Megeath, S. Thomas 205.01 Megeath, Thomas 108.07 Morris, Mark 207.03 Mundy, Lee 107.02 Mundy, Lee G. 108.06 Myers, Phil 306.02 Ntormousi, Evangelia 107.03 Öberg, Karin 107.04 Ostriker, Eve 108.13 Ostriker, Eve C. 105.01 Paladini, Roberta 207.05 Peretto, Nicolas 301.01 Pineda, Jaime E. 204.01 Rao, Ramprasad 206.02 Sadavoy, Sarah 207.02 Sahai, Raghvendra 207.03 Samuels, Charles 108.02 Sandell, Goeran 307.01 Schap, William J 307.02 Schnee, Scott 107.01 Segura-Cox, Dominique 206.01 Seo, Youngmin 108.05 Shirley, Yancy 108.03 Shirley, Yancy L 108.05 Smith, Rowan 300.01 Storm, Shaye 108.06 Storm, Shaye 107.02 Svoboda, Brian E. 108.03 Tafalla, Mario 103.01 Tan, Jonathan 303.01 Terebey, Susan 203.01 Tibbs, Christopher T 207.05 Vazquez-Semadeni, Enrique 106.01 Won Lee, Chang 202.01 Wu, Yuefang 107.05 Yang, Yao-Lun 207.04 Zhang, Qizhou 307.03, 307.04 Zhang, Qizhou 302.01 Zinnecker, Hans 307.01