Gamma-Ray Imaging Observations of the Crab and Cygnus Regions
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Far-Infrared Observations of a Massive Cluster Forming in the Monoceros R2 filament Hub? T
Astronomy & Astrophysics manuscript no. monr2_hobys˙final˙corrected c ESO 2017 December 5, 2017 Far-infrared observations of a massive cluster forming in the Monoceros R2 filament hub? T. S. M. Rayner1??, M. J. Griffin1, N. Schneider2; 3, F. Motte4; 5, V. K¨onyves5, P. Andr´e5, J. Di Francesco6, P. Didelon5, K. Pattle7, D. Ward-Thompson7, L. D. Anderson8, M. Benedettini9, J.-P. Bernard10, S. Bontemps3, D. Elia9, A. Fuente11, M. Hennemann5, T. Hill5; 12, J. Kirk7, K. Marsh1, A. Men'shchikov5, Q. Nguyen Luong13; 14, N. Peretto1, S. Pezzuto9, A. Rivera-Ingraham15, A. Roy5, K. Rygl16, A.´ S´anchez-Monge2, L. Spinoglio9, J. Tig´e17, S. P. Trevi~no-Morales18, and G. J. White19; 20 1 Cardiff School of Physics and Astronomy, Cardiff University, Queen's Buildings, The Parade, Cardiff, Wales, CF24 3AA, UK 2 I. Physik. Institut, University of Cologne, 50937 Cologne, Germany 3 Laboratoire d'Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, all´eeG. Saint-Hilaire, 33615 Pessac, France 4 Universit´eGrenoble Alpes, CNRS, Institut de Planetologie et d'Astrophysique de Grenoble, 38000 Grenoble, France 5 Laboratoire AIM, CEA/IRFU { CNRS/INSU { Universit´eParis Diderot, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France 6 NRC, Herzberg Institute of Astrophysics, Victoria, Canada 7 Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK 8 Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506, USA 9 INAF { Istituto di Astrofisica e Planetologia Spaziali, via Fosso del Cavaliere 100, I-00133 Roma, Italy 10 -
Data Delivery Document
The CygnusX Legacy Project Data Description: Delivery 1: July 2011 CygnusX team: Joseph L. Hora1 (PI), Sylvain Bontemps2, Tom Megeath3, Nicola Schneider4 , Frederique Motte4, Sean Carey5, Robert Simon6, Eric Keto1, Howard Smith1, Lori Allen7, Rob Gutermuth8, Giovanni Fazio1, Kathleen Kraemer9, Don Mizuno10, Stephan Price9, Joseph Adams11, Xavier Koenig12 1Harvard-Smithsonian Center for Astrophysics, 2Observatoire de Bordeaux, 3University of Toledo, 4CEA-Saclay, 5Spitzer Science Center, 6Universität zu Köln, 7NOAO, 8Smith College, 9Air Force Research Lab, 10Boston College, 11Cornell University, 12Goddard Space Flight Center Table of Contents 1. Project Summary ..................................................................................................................... 3 1.1 IRAC observations ........................................................................................................... 3 1.2 MIPS observations ........................................................................................................... 4 1.3 Data reduction .................................................................................................................. 5 1.3.1 IRAC reduction ......................................................................................................... 5 1.3.2 MIPS reduction ......................................................................................................... 7 2. Point Source Catalog.............................................................................................................. -
Discovery of a Wolf–Rayet Star Through Detection of Its Photometric Variability
The Astronomical Journal, 143:136 (6pp), 2012 June doi:10.1088/0004-6256/143/6/136 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. DISCOVERY OF A WOLF–RAYET STAR THROUGH DETECTION OF ITS PHOTOMETRIC VARIABILITY Colin Littlefield1, Peter Garnavich2, G. H. “Howie” Marion3,Jozsef´ Vinko´ 4,5, Colin McClelland2, Terrence Rettig2, and J. Craig Wheeler5 1 Law School, University of Notre Dame, Notre Dame, IN 46556, USA 2 Physics Department, University of Notre Dame, Notre Dame, IN 46556, USA 3 Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA 4 Department of Optics, University of Szeged, Hungary 5 Astronomy Department, University of Texas, Austin, TX 78712, USA Received 2011 November 9; accepted 2012 April 4; published 2012 May 2 ABSTRACT We report the serendipitous discovery of a heavily reddened Wolf–Rayet star that we name WR 142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low- resolution spectroscopy revealed a strong emission line at 7100 Å, suggesting an unusual object and prompting further study. A spectrum taken with the Hobby–Eberly Telescope confirms strong He ii emission and an N iv 7112 Å line consistent with a nitrogen-rich Wolf–Rayet star of spectral class WN6. Analysis of the He ii line strengths reveals no detectable hydrogen in WR 142b. A blue-sensitive spectrum obtained with the Large Binocular Telescope shows no evidence for a hot companion star. The continuum shape and emission line ratios imply a reddening of E(B − V ) = 2.2–2.6 mag. -
Cygnus X-3 and the Case for Simultaneous Multifrequency
by France Anne-Dominic Cordova lthough the visible radiation of Cygnus A X-3 is absorbed in a dusty spiral arm of our gal- axy, its radiation in other spectral regions is observed to be extraordinary. In a recent effort to better understand the causes of that radiation, a group of astrophysicists, including the author, carried 39 Cygnus X-3 out an unprecedented experiment. For two days in October 1985 they directed toward the source a variety of instru- ments, located in the United States, Europe, and space, hoping to observe, for the first time simultaneously, its emissions 9 18 Gamma Rays at frequencies ranging from 10 to 10 Radiation hertz. The battery of detectors included a very-long-baseline interferometer consist- ing of six radio telescopes scattered across the United States and Europe; the Na- tional Radio Astronomy Observatory’s Very Large Array in New Mexico; Caltech’s millimeter-wavelength inter- ferometer at the Owens Valley Radio Ob- servatory in California; NASA’s 3-meter infrared telescope on Mauna Kea in Ha- waii; and the x-ray monitor aboard the European Space Agency’s EXOSAT, a sat- ellite in a highly elliptical, nearly polar orbit, whose apogee is halfway between the earth and the moon. In addition, gamma- Wavelength (m) ray detectors on Mount Hopkins in Ari- zona, on the rim of Haleakala Crater in Fig. 1. The energy flux at the earth due to electromagnetic radiation from Cygnus X-3 as a Hawaii, and near Leeds, England, covered function of the frequency and, equivalently, energy and wavelength of the radiation. -
Globules and Pillars in Cygnus X II
A&A 599, A37 (2017) Astronomy DOI: 10.1051/0004-6361/201628962 & c ESO 2017 Astrophysics Globules and pillars in Cygnus X II. Massive star formation in the globule IRAS 20319+3958?,?? A. A. Djupvik1, F. Comerón2, and N. Schneider3 1 Nordic Optical Telescope, Rambla José Ana Fernández Pérez 7, 38711 Breña Baja, Spain e-mail: [email protected] 2 European Southern Observatory, 3107 Alonso de Córdova, Vitacura, Santiago, Chile 3 KOSMA, I. Physik. Institut, Zülpicher Str. 77, Universität Köln, 50937 Köln, Germany Received 17 May 2016 / Accepted 9 November 2016 ABSTRACT Globules and pillars, impressively revealed by the Spitzer and Herschel satellites, for example, are pervasive features found in regions of massive star formation. Studying their embedded stellar populations can provide an excellent laboratory to test theories of triggered star formation and the features that it may imprint on the stellar aggregates resulting from it. We studied the globule IRAS 20319+3958 in Cygnus X by means of visible and near-infrared imaging and spectroscopy, complemented with mid-infrared Spitzer/IRAC imaging, in order to obtain a census of its stellar content and the nature of its embedded sources. Our observations show that the globule contains an embedded aggregate of about 30 very young (.1 Myr) stellar objects, for which we estimate a total mass of ∼90 M . The most massive members are three systems containing early B-type stars. Two of them most likely produced very compact H II regions, one of them being still highly embedded and coinciding with a peak seen in emission lines characterising the photon dominated region (PDR). -
The Outskirts of Cygnus OB2 ⋆
Astronomy & Astrophysics manuscript no. 9917 c ESO 2008 May 27, 2008 The outskirts of Cygnus OB2 ? F. Comeron´ 1??, A. Pasquali2, F. Figueras3, and J. Torra3 1 European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany e-mail: [email protected] 2 Max-Planck-Institut fur¨ Astronomie, Konigstuhl¨ 17, D-69117 Heidelberg, Germany e-mail: [email protected] 3 Departament d'Astronomia i Meteorologia, Universitat de Barcelona, E-08028 Barcelona, Spain e-mail: [email protected], [email protected] Received; accepted ABSTRACT Context. Cygnus OB2 is one of the richest OB associations in the local Galaxy, and is located in a vast complex containing several other associations, clusters, molecular clouds, and HII regions. However, the stellar content of Cygnus OB2 and its surroundings remains rather poorly known largely due to the considerable reddening in its direction at visible wavelength. Aims. We investigate the possible existence of an extended halo of early-type stars around Cygnus OB2, which is hinted at by near- infrared color-color diagrams, and its relationship to Cygnus OB2 itself, as well as to the nearby association Cygnus OB9 and to the star forming regions in the Cygnus X North complex. Methods. Candidate selection is made with photometry in the 2MASS all-sky point source catalog. The early-type nature of the selected candidates is conrmed or discarded through our infrared spectroscopy at low resolution. In addition, spectral classications in the visible are presented for many lightly-reddened stars. Results. A total of 96 early-type stars are identied in the targeted region, which amounts to nearly half of the observed sample. -
The Broad-Band Spectrum of Cygnus X-1 Measured by INTEGRAL
A&A 446, 591–602 (2006) Astronomy DOI: 10.1051/0004-6361:20053068 & c ESO 2006 Astrophysics The broad-band spectrum of Cygnus X-1 measured by INTEGRAL M. Cadolle Bel1,2,P.Sizun1, A. Goldwurm1,2, J. Rodriguez1,3,4,P.Laurent1,2,A.A.Zdziarski5, L. Foschini6, P. Goldoni1,2, C. Gouiffes` 1, J. Malzac7, E. Jourdain7, and J.-P. Roques7 1 Service d’Astrophysique, CEA-Saclay, 91191 Gif-Sur-Yvette, France e-mail: [email protected] 2 APC-UMR 7164, 11 place M. Berthelot, 75231 Paris, France 3 AIM-UMR 7158, France 4 ISDC, 16 Chemin d’Ecogia, 1290 Versoix, Switzerland 5 N. Copernicus Astronomical Center, 00-716 Warsaw, Poland 6 INAF/IASF, Sezione di Bologna, Via Gobetti 101, 40129 Bologna, Italy 7 Centre d’Etude´ Spatiale des Rayonnements, 31028 Toulouse, France Received 15 March 2005 / Accepted 31 August 2005 ABSTRACT The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations. These data provide evidence for significant spectral variations over the period. In the framework of the accreting black hole phenomenology, the source was most of the time in the Hard State and occasionally switched to the so-called “Intermediate State”. Using the results of the analysis performed on these data, we present and compare the spectral properties of the source over the whole energy range (5 keV–1 MeV) covered by the high-energy instruments on board INTEGRAL, in both observed spectral states. Fe line and reflection component evolution occurs with spectral changes in the hard and soft components. -
The Astronomical Zoo: Discovery and Classification
Theme 6: The Astronomical Zoo: discovery and classification 6.1 Discovery As discussed earlier, astronomy is atypical among the exact sciences in that discovery normally precedes understanding, sometimes by many years. Astronomical discovery is usually driven by availability of technology rather than by theoretical predictions or speculation. Figure 6.1, redrawn from Martin Harwit’s Cosmic Discovery (MIT Press, 1984), show how the rate of disco- very of “astronomical phenomena” (i.e. classes of object, rather than properties such as dis- tance) has increased over time (the line is a rough fit to an exponential), and 50 the age of the necessary technology at the time the discovery was made. (I 40 have not attempted to update Harwit’s data, because the decision as to what 30 constitutes a new phenomenon is sub- 20 jective to some degree; he puts in seve- ral items that I would not have regar- 10 ded as significant, omits some I would total numberof classes have listed, and doesn’t always assign 0 the same date as I would.) 1550 1600 1650 1700 1750 1800 1850 1900 1950 date Note that the pace of discoveries accel- erates in the 20th century, and the time Impact of new technology lag between the availability of the ne- 15 cessary technology and the actual dis- covery decreases. This is likely due to 10 the greater number of working astro- <1954 nomers: if the technology to make the 5 discovery exists, someone will make it. 1954-74 However, Harwit also makes the point 0 that the discoveries made in the period Numberof discoveries <5 5-10 10-25 25-50 >50 1954−74 were generally (~85%) made Age of required technology (years) by people who were not initially trained in astronomy (mostly physi- Figure 6.1: astronomical discoveries. -
X-Ray Studies of Ultraluminous X-Ray Sources
Durham E-Theses X-ray studies of ultraluminous X-ray sources LUANGTIP, WASUTEP How to cite: LUANGTIP, WASUTEP (2015) X-ray studies of ultraluminous X-ray sources, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/11266/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk X-ray studies of ultraluminous X-ray sources Wasutep Luangtip A Thesis presented for the degree of Doctor of Philosophy Centre for Extragalactic Astronomy Department of Physics University of Durham United Kingdom September 2015 X-ray studies of ultraluminous X-ray sources Wasutep Luangtip Submitted for the degree of Doctor of Philosophy September 2015 Abstract Ultraluminous X-ray sources (ULXs) are extra-galactic, non-nuclear point sources, with X-ray luminosities brighter than 1039 erg s−1, in excess of the Eddington limit for 10 M⊙ black holes. -
The Dependence of Protostellar Luminosity on Environment in the Cygnus-X Star-Forming Complex
The Dependence of Protostellar Luminosity on Environment in the Cygnus-X Star-Forming Complex E. Kryukova1, S. T. Megeath1, J. L. Hora2, R. A. Gutermuth3, S. Bontemps4,5, K. Kraemer6, M. Hennemann7, N. Schneider4,5, Howard A. Smith2, F. Motte7 ABSTRACT The Cygnus-X star-forming complex is one of the most active regions of low and high mass star formation within 2 kpc of the Sun. Using mid-infrared pho- tometry from the IRAC and MIPS Spitzer Cygnus-X Legacy Survey, we have identified over 1800 protostar candidates. We compare the protostellar lumi- nosity functions of two regions within Cygnus-X: CygX-South and CygX-North. These two clouds show distinctly different morphologies suggestive of dissimilar star-forming environments. We find the luminosity functions of these two regions are statistically different. Furthermore, we compare the luminosity functions of protostars found in regions of high and low stellar density within Cygnus-X and find that the luminosity function in regions of high stellar density is biased to higher luminosities. In total, these observations provide further evidence that the luminosities of protostars depend on their natal environment. We discuss the implications this dependence has for the star formation process. Subject headings: infrared: stars, stars: protostars, stars: formation, stars: lu- minosity function 1Ritter Astrophysical Observatory, Department of Physics and Astronomy, University of Toledo, Toledo, OH; [email protected] 2Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 3Department of Astronomy, University of Massachusetts, Amherst, MA 4Univ. Bordeaux, LAB, UMR 5804, F-33270, Floirac, France. 5CNRS, LAB, UMR 5804, F-33270, Floirac, France 6Institute for Scientific Research, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467, USA 7Laboratoire AIM, CEA/IRFU - CNRS/INSU - Universit´eParis Diderot, Service d’Astrophysique, Bˆat. -
III. the S106 Molecular Cloud As Part of the Cygnus X Cloud Complex
A&A 474, 873–882 (2007) Astronomy DOI: 10.1051/0004-6361:20077540 & c ESO 2007 Astrophysics A multiwavelength study of the S106 region III. The S106 molecular cloud as part of the Cygnus X cloud complex N. Schneider1,4,R.Simon4, S. Bontemps2, F. Comerón3, and F. Motte1 1 DAPNIA/SAp CEA/DSM, Laboratoire AIM CNRS - Université Paris Diderot, 91191 Gif-sur-Yvette, France e-mail: [email protected] 2 OASU/LAB-UMR5804, CNRS, Université Bordeaux 1, 33270 Floirac, France 3 ESO, Karl-Schwarzschild Str. 2, 85748 Garching, Germany 4 I. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany Received 26 March 2007 / Accepted 15 August 2007 ABSTRACT Context. The distance to the wellknown bipolar nebula S106 and its associated molecular cloud is highly uncertain. Values between 0.5 and 2 kpc are given in the literature, favoring a view of S106 as an isolated object at a distance of 600 pc as part of the “Great Cygnus Rift”. However, there is evidence that S106 is physically associated with the Cygnus X complex at a distance of ∼1.7 kpc (Schneider et al. 2006, A&A, 458, 855). In this case, S106 is a more massive and more luminous star forming site than previously thought. Aims. We aim to understand the large-scale distribution of molecular gas in the S106 region, its possible association with other clouds in the Cygnus X south region, and the impact of UV radiation on the gas. This will constrain the distance to S106. Methods. We employ a part of an extended 13CO and C18O1→ 0 survey, performed with the FCRAO, and data from the MSX and Spitzer satellites to study the spatial distribution and correlation of molecular cloud/PDR interfaces in Cygnus X south. -
A Spitzer View of Star Formation in the Cygnus X North Complex I
University of Massachusetts Amherst ScholarWorks@UMass Amherst Astronomy Department Faculty Publication Series Astronomy 2010 A SPITZER VIEW OF STAR FORMATION IN THE CYGNUS X NORTH COMPLEX I. M. Beerer X. P. Koenig J. L. Hora R. A. Gutermuth University of Massachusetts - Amherst Follow this and additional works at: https://scholarworks.umass.edu/astro_faculty_pubs Part of the Astrophysics and Astronomy Commons Recommended Citation Beerer, I. M.; Koenig, X. P.; Hora, J. L.; and Gutermuth, R. A., "A SPITZER VIEW OF STAR FORMATION IN THE CYGNUS X NORTH COMPLEX" (2010). The Astrophysical Journal. 119. 10.1088/0004-637X/720/1/679 This Article is brought to you for free and open access by the Astronomy at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Astronomy Department Faculty Publication Series by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Accepted for publication in The Astrophysical Journal A Preprint typeset using LTEX style emulateapj v. 11/10/09 A SPITZER VIEW OF STAR FORMATION IN THE CYGNUS X NORTH COMPLEX I. M. Beerer,1 X. P. Koenig,2 J. L. Hora2, R. A. Gutermuth,34 S. Bontemps,5 S. T. Megeath,6, N. Schneider,5 F. Motte7, S. Carey,8 R. Simon,9 E. Keto,2 H. A. Smith,2 L. E. Allen,8 G. G. Fazio,2 K. E. Kraemer,11 S. Price,11, D. Mizuno,12 J. D. Adams,13 J. Hernandez,´ 14 P. W. Lucas15 Accepted for publication in The Astrophysical Journal ABSTRACT We present new images and photometry of the massive star forming complex Cygnus X obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope.