Magnetized Filamentary Gas Flows Feeding the Young Embedded
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The Dunhuang Chinese Sky: a Comprehensive Study of the Oldest Known Star Atlas
25/02/09JAHH/v4 1 THE DUNHUANG CHINESE SKY: A COMPREHENSIVE STUDY OF THE OLDEST KNOWN STAR ATLAS JEAN-MARC BONNET-BIDAUD Commissariat à l’Energie Atomique ,Centre de Saclay, F-91191 Gif-sur-Yvette, France E-mail: [email protected] FRANÇOISE PRADERIE Observatoire de Paris, 61 Avenue de l’Observatoire, F- 75014 Paris, France E-mail: [email protected] and SUSAN WHITFIELD The British Library, 96 Euston Road, London NW1 2DB, UK E-mail: [email protected] Abstract: This paper presents an analysis of the star atlas included in the medieval Chinese manuscript (Or.8210/S.3326), discovered in 1907 by the archaeologist Aurel Stein at the Silk Road town of Dunhuang and now held in the British Library. Although partially studied by a few Chinese scholars, it has never been fully displayed and discussed in the Western world. This set of sky maps (12 hour angle maps in quasi-cylindrical projection and a circumpolar map in azimuthal projection), displaying the full sky visible from the Northern hemisphere, is up to now the oldest complete preserved star atlas from any civilisation. It is also the first known pictorial representation of the quasi-totality of the Chinese constellations. This paper describes the history of the physical object – a roll of thin paper drawn with ink. We analyse the stellar content of each map (1339 stars, 257 asterisms) and the texts associated with the maps. We establish the precision with which the maps are drawn (1.5 to 4° for the brightest stars) and examine the type of projections used. -
NGC 1333 Plunkett Et
Outflows in protostellar clusters: a multi-wavelength, multi-scale view Adele L. Plunkett1, H. G. Arce1, S. A. Corder2, M. M. Dunham1, D. Mardones3 1-Yale University; 2-ALMA; 3-Universidad de Chile Interferometer and Single Dish Overview Combination FCRAO-only v=-2 to 6 km/s FCRAO-only v=10 to 17 km/s K km s While protostellar outflows are generally understood as necessary components of isolated star formation, further observations are -1 needed to constrain parameters of outflows particularly within protostellar clusters. In protostellar clusters where most stars form, outflows impact the cluster environment by injecting momentum and energy into the cloud, dispersing the surrounding gas and feeding turbulent motions. Here we present several studies of very dense, active regions within low- to intermediate-mass Why: protostellar clusters. Our observations include interferometer (i.e. CARMA) and single dish (e.g. FCRAO, IRAM 30m, APEX) To recover flux over a range of spatial scales in the region observations, probing scales over several orders of magnitude. How: Based on these observations, we calculate the masses and kinematics of outflows in these regions, and provide constraints for Jy beam km s Joint deconvolution method (Stanimirovic 2002), CARMA-only v=-2 to 6 km/s CARMA-only v=10 to 17 km/s models of clustered star formation. These results are presented for NGC 1333 by Plunkett et al. (2013, ApJ accepted), and -1 comparisons among star-forming regions at different evolutionary stages are forthcoming. using the analysis package MIRIAD. -1 1212COCO Example: We mapped NGC 1333 using CARMA with a resolution of ~5’’ (or 0.006 pc, 1000 AU) in order to Our study focuses on Class 0 & I outflow-driving protostars found in clusters, and we seek to detect outflows and associate them with their driving sources. -
The Discovery of Herbig-Haro Objects in Ldn 673
Draft version December 4, 2017 Typeset using LATEX default style in AASTeX61 THE DISCOVERY OF HERBIG-HARO OBJECTS IN LDN 673 T. A. Rector1 | R. Y. Shuping2 | L. Prato3 | H. Schweiker4, 5, 6 | 1Department of Physics and Astronomy, University of Alaska Anchorage, Anchorage, AK 99508, USA 2Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301, USA 3Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001, USA 4National Optical Astronomy Observatory, Tucson, AZ 85719, USA 5Kitt Peak National Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation. 6WIYN Observatory, Tucson, AZ 85719, USA ABSTRACT We report the discovery of twelve faint Herbig-Haro (HH) objects in LDN 673 found using a novel color-composite imaging method that reveals faint Hα emission in complex environments. Follow-up observations in [S II] confirmed their classification as HH objects. Potential driving sources are identified from the Spitzer c2d Legacy Program catalog and other infrared observations. The twelve new HH objects can be divided into three groups: Four are likely associated with a cluster of eight YSO class I/II IR sources that lie between them; five are colinear with the T Tauri multiple star system AS 353, and are likely driven by the same source as HH 32 and HH 332; three are bisected by a very red source that coincides with an infrared dark cloud. We also provide updated coordinates for the three components of HH 332. Inaccurate numbers were given for this object in the discovery paper. -
Arxiv:2005.05466V1 [Astro-Ph.GA] 11 May 2020 Surface Density
Draft version May 13, 2020 Typeset using LATEX preprint style in AASTeX62 Star-Gas Surface Density Correlations in Twelve Nearby Molecular Clouds I: Data Collection and Star-Sampled Analysis Riwaj Pokhrel,1, 2 Robert A. Gutermuth,2 Sarah K. Betti,2 Stella S. R. Offner,3 Philip C. Myers,4 S. Thomas Megeath,1 Alyssa D. Sokol,2 Babar Ali,5 Lori Allen,6 Tom S. Allen,7, 8 Michael M. Dunham,9 William J. Fischer,10 Thomas Henning,11 Mark Heyer,2 Joseph L. Hora,4 Judith L. Pipher,12 John J. Tobin,13 and Scott J. Wolk4 1Ritter Astrophysical Research Center, Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606, USA 2Department of Astronomy, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USA 3Department of Astronomy, The University of Texas at Austin, 2500 Speedway, Austin, TX 78712, USA 4Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 5Space Sciences Institute, 4750 Walnut Street, Suite 205, Boulder, CO, USA 6National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ, 85719, USA 7Portland State University, 1825 SW Broadway Portland, OR 97207, USA 8Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001, USA 9Department of Physics, State University of New York at Fredonia, 280 Central Ave, Fredonia, NY 14063, USA 10Space Telescope Science Institute, Baltimore, MD 21218, USA 11Max-Planck-Institute for Astronomy, K¨onigstuhl17, D-69117 Heidelberg, Germany 12Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA 13National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA (Received ...; Revised ...; Accepted May 13, 2020) Submitted to ApJ ABSTRACT We explore the relation between the stellar mass surface density and the mass surface density of molecular hydrogen gas in twelve nearby molecular clouds that are located at <1.5 kpc distance. -
The Future of the GBT
The Future of the GBT Felix J. Lockman NRAO Green Bank Arecibo, July 2009 UNOFFICIAL The Future of the GBT Felix J. Lockman NRAO Green Bank Arecibo, July 2009 Characteristics of the GBT Large Collecting Area Sensitive to Low Surface Brightness Sky Coverage & Tracking (>85%) Angular Resolution Frequency Coverage Radio Quiet Zone Unblocked Aperture state-of-art receivers & detectors modern control software flexible scheduling Unique capabilities which complement EVLA, VLBA, and ALMA The Advantage of Unblocked Optics Dynamic Range Near sidelobes reduced by a factor >10 from conventional antennas Gain & Sensitivity The 100 meter diameter GBT performs better than a 120 meter conventional antenna Reduced Interference 2002 panels active surface retroreflectors for future metrology A telescope designed to be enhanced Unique active surface →Unlike any other radio telescope← Green Bank and the GBT A telescope that works well over a factor of 1000 in frequency/wavelength / energy -- equivalent to the range from the infrared (10μ) to the soft X-ray (0.01μ) GALEX HST Chandra Spitzer “...just hitting its stride” Future Prospects & Development at NRAO and in the US Radio Community ~ 2008 NRAO Staff Retreat 4 AOC Auditorium, NRAO, Socorro, NM ~ April 10-11, 2008 A telescope for fundamental physics The fastest pulsars test our understanding of matter at the most extreme densities “A Radio Pulsar Spinning at 716 Hz” Hessels et al 2006 Science A telescope for fundamental physics The fastest pulsars test our understanding of matter at the most extreme densities -
Sydney Observatory Night Sky Map September 2012 a Map for Each Month of the Year, to Help You Learn About the Night Sky
Sydney Observatory night sky map September 2012 A map for each month of the year, to help you learn about the night sky www.sydneyobservatory.com This star chart shows the stars and constellations visible in the night sky for Sydney, Melbourne, Brisbane, Canberra, Hobart, Adelaide and Perth for September 2012 at about 7:30 pm (local standard time). For Darwin and similar locations the chart will still apply, but some stars will be lost off the southern edge while extra stars will be visible to the north. Stars down to a brightness or magnitude limit of 4.5 are shown. To use this chart, rotate it so that the direction you are facing (north, south, east or west) is shown at the bottom. The centre of the chart represents the point directly above your head, called the zenith, and the outer circular edge represents the horizon. h t r No Star brightness Moon phase Last quarter: 08th Zero or brighter New Moon: 16th 1st magnitude LACERTA nd Deneb First quarter: 23rd 2 CYGNUS Full Moon: 30th rd N 3 E LYRA th Vega W 4 LYRA N CORONA BOREALIS HERCULES BOOTES VULPECULA SAGITTA PEGASUS DELPHINUS Arcturus Altair EQUULEUS SERPENS AQUILA OPHIUCHUS SCUTUM PISCES Moon on 23rd SERPENS Zubeneschamali AQUARIUS CAPRICORNUS E SAGITTARIUS LIBRA a Saturn Centre of the Galaxy Antares Zubenelgenubi t s Antares VIRGO s t SAGITTARIUS P SCORPIUS P e PISCESMICROSCOPIUM AUSTRINUS SCORPIUS Mars Spica W PISCIS AUSTRINUS CORONA AUSTRALIS Fomalhaut Centre of the Galaxy TELESCOPIUM LUPUS ARA GRUSGRUS INDUS NORMA CORVUS INDUS CETUS SCULPTOR PAVO CIRCINUS CENTAURUS TRIANGULUM -
A Multi-Transition Molecular Line Study of Infrared Dark Cloud G331.71+00.59
Research in Astron. Astrophys. 2013 Vol. 13 No. 1, 28 – 38 Research in http://www.raa-journal.org http://www.iop.org/journals/raa Astronomy and Astrophysics A multi-transition molecular line study of infrared dark cloud G331.71+00.59 Nai-Ping Yu and Jun-Jie Wang National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China; [email protected] NAOC-TU Joint Center for Astrophysics, Lhasa 850000, China Received 2012 March 12; accepted 2012 August 3 Abstract Using archive data from the Millimeter Astronomy Legacy Team Survey at 90 GHz (MALT90), carried out using the Mopra 22-m telescope, we made the first multi-transition molecular line study of infrared dark cloud (IRDC) MSXDC G331.71+00.59. Two molecular cores were found embedded in this IRDC. Each of these cores is associated with a known extended green object (EGO), indicating places of massive star formation. The HCO+ (1–0) and HNC (1–0) transitions show promi- nent blue or red asymmetric structures, suggesting outflow and inflow activities of young stellar objects (YSOs). Other detected molecular lines include H13CO+ (1– 0), C2H (1–0), HC3N (10–9), HNCO(40;4–30;3) and SiO (2–1), which are typical of hot cores and outflows. We regard the two EGOs as evolving from the IRDC to hot cores. Using public GLIMPS data, we investigate the spectral energy distribution of EGO G331.71+0.60. Our results support this EGO being a massive YSO driving the outflow. G331.71+0.58 may be at an earlier evolutionary stage. -
Abstract Book & Logistics
MASSIVE STAR FORMATION 2007 Observations confront Theory September 10 – 14, 2007 Convention Centre Heidelberg, Germany ABSTRACT BOOK & LOGISTICS 2 List of Contents Heidelberg Map Extract Page 7 Room Plan of the Convention Center Page 9 Social Events Page 11 Proceedings Information Page 13 Scientific Program Page 15 Abstracts for Talk Contributions Page 25 Abstracts for Poster Contributions Page 91 List of Participants Page 245 3 4 LOGISTICS 5 6 A Cutout Map of Heidelberg 7 The image shows a cutout from the Heidelberg map included in your conference papers. Three impor- tant locations, the Convention Centre (“Stadthalle”), the Heidelberg Castle (“Schloß”), and the University including the Old Assembly Hall are indicated with ellipses. Note that the Konigstuhl¨ Hill with the Lan- dessternwarte and MPIA is not included here. 8 A Sketch of the Room Plan in the Convention Center Internet cafe Main hall for talks and posters Coffee Reception Area Desk Main Entrance Internet Connection We provide an “Internet Cafe”´ with 8 comput- ers and additional plugins for laptops. Furthermore, the Coffee Area will be wireless and you can easily connect to the Internet via a normal DHCP connection from there. The WLAN net will have the name Kon- gresshaus. Convention Center Telephone during the meeting The Convention Center provides a telephone number for callers from outside: +49 (0)6221 14 22 812 9 10 Social Events Beside the scientific program, we have arranged for some “Social Events” that, we hope, are a nice and light addition to the concentrated series of talks during the conference. Welcome Reception On Monday, September 10, we will have the welcome reception at the Heidelberg Castle at 19:30 in the evening. -
Early Stages of Massive Star Formation
Early Stages of Massive Star Formation Vlas Sokolov Munchen¨ 2018 Early Stages of Massive Star Formation Vlas Sokolov Dissertation an der Fakultat¨ fur Physik der Ludwig–Maximilians–Universitat¨ Munchen¨ vorgelegt von Vlas Sokolov aus Kyjiw, Ukraine Munchen,¨ den 13 Juli 2018 Erstgutachter: Prof. Dr. Paola Caselli Zweitgutachter: Prof. Dr. Markus Kissler-Patig Tag der mundlichen¨ Prufung:¨ 27 August 2018 Contents Zusammenfassung xv Summary xvii 1 Introduction1 1.1 Overview......................................1 1.2 The Interstellar Medium..............................2 1.2.1 Molecular Clouds..............................5 1.3 Low-mass Star Formation..............................9 1.4 High-Mass Star and Cluster Formation....................... 12 1.4.1 Observational perspective......................... 14 1.4.2 Theoretical models............................. 16 1.4.3 IRDCs as the initial conditions of massive star formation......... 18 1.5 Methods....................................... 20 1.5.1 Radio Instrumentation........................... 20 1.5.2 Radiative Processes in the Dark Clouds.................. 22 1.5.3 Blackbody Dust Emission......................... 23 1.5.4 Ammonia inversion transitions....................... 26 1.6 This Thesis..................................... 28 2 Temperature structure and kinematics of the IRDC G035.39–00.33 31 2.1 Abstract....................................... 31 2.2 Introduction..................................... 32 2.3 Observations.................................... 33 2.3.1 GBT observations............................ -
Arxiv:2004.14050V1 [Astro-Ph.SR] 29 Apr 2020
Draft version April 30, 2020 Typeset using LATEX twocolumn style in AASTeX63 A detailed analysis on the cloud structure and dynamics in Aquila Rift Tomomi Shimoikura,1 Kazuhito Dobashi,2 Yoshiko Hatano,2 and Fumitaka Nakamura3, 4 1Otsuma Women's University ` Chiyoda-ku,Tokyo, 102-8357, Japan 2Tokyo Gakugei University Koganei, 184-8501, Tokyo 3National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588, Japan 4Department of Astronomical Science, School of Physical Science, SOKENDAI (The Graduate University for Advanced Studies), Osawa, Mitaka, Tokyo 181-8588, Japan (Accepted April 23, 2020) Submitted to APJ ABSTRACT We present maps in several molecular emission lines of a 1 square-degree region covering the W40 and Serpens South molecular clouds belonging to the Aquila Rift complex. The observations were made with the 45 m telescope at the Nobeyama Radio Observatory. We found that the 12CO and 13CO emission lines consist of several velocity components with different spatial distributions. The component that forms the main cloud of W40 and Serpens South, which we call the \main component", −1 −1 has a velocity of VLSR ' 7 km s . There is another significant component at VLSR ' 40 km s , which we call the \40 km s−1 component". The latter component is mainly distributed around two young clusters: W40 and Serpens South. Moreover, the two components look spatially anti-correlated. Such spatial configuration suggests that the star formation in W40 and Serpens South was induced by the collision of the two components. We also discuss a possibility that the 40 km s−1 component consists of gas swept up by superbubbles created by SNRs and stellar winds from the Scorpius-Centaurus Association. -
Eric Keto Publications REFEREED JOURNALS 2014
{ 1 { Eric Keto Publications REFEREED JOURNALS 2014 (1) Chitsazzadeh, S., Di Francesco, J., Schnee, S., Friesen, R. K., Shimajiri, Y., Langston, G. I., Sadavoy, S. I., Bourke, T. L., Keto, E., Pineda, J. E., Takakuwa, S., Tatematsu, K., 2014, ApJ, 790, 129-150 "Physical and Chemical Characteristics of L1689-SMM16, an Oscillating Prestellar Core in Ophiuchus" (2) Zhang, Q. Qiu, K., Girart, J., Hauyu, L., Tang, Y.-W., Koch, P., Li, Z.-Y., Keto, E., Ho, P.T.P., Rao, R., Lai, S.-P., Ching, T.-C., Frau, P., Chen, H.-H., Li, H.-B., Padovani, M., Bontemps, S., Csengeri, T., Juarez, C., 2014, ApJ in press, arXiv:1407.3984, "Magnetic Fields and Massive Star Formation" (3) Inoue, M., Algaba-Marcos, J. C., Asada, K., Chang, C.-C., Chen, M.-T., Han, J., Hi- rashita, H., Ho, P.T.P., Hsieh, S.-N., Huang, T., Jiang, H., Koch, P. M., Kubo, D. Y., Kuo, C.-Y., Liu, B., Martin-Cocher, P., Matsushita, S., Meyer-Zhao, Z., Naka- mura, M., Nishioka, H., Nystrom, G., Pradel, N., Pu, H.-Y., Raffin, P. A., Shen, H.-Y., Snow, W., Srinivasan, R., Wei, T.-S., Blundell, R., Burgos, R., Grimes, P., Keto, E., Paine, S., Patel, N., Sridharan, T. K., Doeleman, S. S., Fish, V., Brisken, W., Napier, P., 2014, Radio Science Journal, in press, arXiv:1407.2450 "Greenland Telescope Project | Direct Confirmation of Black Hole with Sub-millimeter VLBI" (4) van Loo, S., Keto, E., Zhang, Q., 2014, ApJ, 789, 37-50, "Core and Filament Formation in Magnetized, Self-gravitating Isothermal Layers" (5) Keto, E., Burkert, A., 2014, MNRAS, 441, 1468-1473, "From filaments to oscillating starless -
Publications 2012
Publications - print summary 27 Feb 2013 1 *Abramowski, A.; Acero, F.; Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Balzer, A.; Barnacka, A.; Barres de Almeida, U.; Becherini, Y.; Becker, J.; and 201 coauthors "A multiwavelength view of the flaring state of PKS 2155-304 in 2006". (C) A&A, 539, 149 (2012). 2 *Ackermann, M.; Ajello, J.; Ballet, G.; Barbiellini, D.; Bastieri, A.; Belfiore; Bellazzini, B.; Berenji, R.D. and 57 coauthors "Periodic emission from the Gamma-Ray Binary 1FGL J1018.6–5856". (O) Science, 335, 189-193 (2012). 3 *Agliozzo, C.; Umana, G.; Trigilio, C.; Buemi, C.; Leto, P.; Ingallinera, A.; Franzen, T.; Noriega-Crespo, A. "Radio detection of nebulae around four luminous blue variable stars in the Large Magellanic Cloud". (C) MNRAS, 426, 181-186 (2012). 4 *Ainsworth, R.E.; Scaife, A.M.M.; Ray, T.P.; Buckle, J.V.; Davies, M.; Franzen, T.M.O.; Grainge, K.J.B.; Hobson, M.P.; Shimwell, T.; and 12 coauthors "AMI radio continuum observations of young stellar objects with known outflows". (O) MNRAS, 423, 1089-1108 (2012). 5 *Allison, J.R.; Curran, S.J.; Emonts, B H.C.; Geréb, K.; Mahony, E.K.; Reeves, S.; Sadler, E.M.; Tanna, A.; Whiting, M.T.; Zwaan, M.A. "A search for 21 cm H I absorption in AT20G compact radio galaxies". (C) MNRAS, 423, 2601-2616 (2012). 6 *Allison, J R.; Sadler, E.M.; Whiting, M.T. "Application of a bayesian method to absorption spectral-line finding in simulated ASKAP Data". (A) PASA, 29, 221-228 (2012). 7 *Alves, M.I.R.; Davies, R.D.; Dickinson, C.; Calabretta, M.; Davis, R.; Staveley-Smith, L.