X-Ray Super-Flares from Pre-Main Sequence Stars: Flare Energetics and Frequency
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Arxiv:2012.09981V1 [Astro-Ph.SR] 17 Dec 2020 2 O
Contrib. Astron. Obs. Skalnat´ePleso XX, 1 { 20, (2020) DOI: to be assigned later Flare stars in nearby Galactic open clusters based on TESS data Olga Maryeva1;2, Kamil Bicz3, Caiyun Xia4, Martina Baratella5, Patrik Cechvalaˇ 6 and Krisztian Vida7 1 Astronomical Institute of the Czech Academy of Sciences 251 65 Ondˇrejov,The Czech Republic(E-mail: [email protected]) 2 Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetsky pr. 13, 119234, Moscow, Russia 3 Astronomical Institute, University of Wroc law, Kopernika 11, 51-622 Wroc law, Poland 4 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotl´aˇrsk´a2, 611 37 Brno, Czech Republic 5 Dipartimento di Fisica e Astronomia Galileo Galilei, Vicolo Osservatorio 3, 35122, Padova, Italy, (E-mail: [email protected]) 6 Department of Astronomy, Physics of the Earth and Meteorology, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynsk´adolina F-2, 842 48 Bratislava, Slovakia 7 Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, H-1121 Budapest, Konkoly Thege Mikl´os´ut15-17, Hungary Received: September ??, 2020; Accepted: ????????? ??, 2020 Abstract. The study is devoted to search for flare stars among confirmed members of Galactic open clusters using high-cadence photometry from TESS mission. We analyzed 957 high-cadence light curves of members from 136 open clusters. As a result, 56 flare stars were found, among them 8 hot B-A type ob- jects. Of all flares, 63 % were detected in sample of cool stars (Teff < 5000 K), and 29 % { in stars of spectral type G, while 23 % in K-type stars and ap- proximately 34% of all detected flares are in M-type stars. -
Curriculum Vitae - 24 March 2020
Dr. Eric E. Mamajek Curriculum Vitae - 24 March 2020 Jet Propulsion Laboratory Phone: (818) 354-2153 4800 Oak Grove Drive FAX: (818) 393-4950 MS 321-162 [email protected] Pasadena, CA 91109-8099 https://science.jpl.nasa.gov/people/Mamajek/ Positions 2020- Discipline Program Manager - Exoplanets, Astro. & Physics Directorate, JPL/Caltech 2016- Deputy Program Chief Scientist, NASA Exoplanet Exploration Program, JPL/Caltech 2017- Professor of Physics & Astronomy (Research), University of Rochester 2016-2017 Visiting Professor, Physics & Astronomy, University of Rochester 2016 Professor, Physics & Astronomy, University of Rochester 2013-2016 Associate Professor, Physics & Astronomy, University of Rochester 2011-2012 Associate Astronomer, NOAO, Cerro Tololo Inter-American Observatory 2008-2013 Assistant Professor, Physics & Astronomy, University of Rochester (on leave 2011-2012) 2004-2008 Clay Postdoctoral Fellow, Harvard-Smithsonian Center for Astrophysics 2000-2004 Graduate Research Assistant, University of Arizona, Astronomy 1999-2000 Graduate Teaching Assistant, University of Arizona, Astronomy 1998-1999 J. William Fulbright Fellow, Australia, ADFA/UNSW School of Physics Languages English (native), Spanish (advanced) Education 2004 Ph.D. The University of Arizona, Astronomy 2001 M.S. The University of Arizona, Astronomy 2000 M.Sc. The University of New South Wales, ADFA, Physics 1998 B.S. The Pennsylvania State University, Astronomy & Astrophysics, Physics 1993 H.S. Bethel Park High School Research Interests Formation and Evolution -
[CII] Emission Properties of the Massive Star-Forming Region
March 2, 2021 [CII] emission properties of the massive star-forming region RCW 36 in a filamentary molecular cloud T. Suzuki1, S. Oyabu1, S. K. Ghosh2, D. K. Ojha2, H. Kaneda1, H. Maeda1, T. Nakagawa3, J. P. Ninan4, S. Vig5, M. Hanaoka1, F. Saito1, S. Fujiwara1, and T. Kanayama1 1 Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan 2 Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India 3 Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa, 252-5210, Japan 4 The Pennsylvania State University, University Park, State College, PA, USA 5 Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695 547, India Received / Accepted ABSTRACT Aims. To investigate properties of [C ii] 158 µm emission of RCW 36 in a dense filamentary cloud. Methods. [C ii] observations of RCW 36 covering an area of ∼ 30′ ×30′ were carried out with a Fabry-Pérot spectrometer aboard a 100-cm balloon-borne far-infrared (IR) telescope with an angular resolution of 90′′. By using AKARI and Herschel images, the spatial distribution of the [C ii] intensity was compared with those of emission from the large grains and polycyclic aromatic hydrocarbon (PAH). Results. The [C ii] emission is spatially in good agreement with shell-like structures of a bipolar lobe observed in IR images, which extend along the direction perpendicular to the direction of a cold dense filament. We found that the [C ii]–160 µm relation for RCW 36 shows higher brightness ratio of [C ii]/160 µm than that for RCW 38, while the [C ii]–9 µm relation for RCW 36 is in good agreement with that for RCW 38. -
Binocular Challenge Here
AHSP Binocular Observing Award Compiled by Phil Harrington www.philharrington.net • To qualify for the BOA pin, you must see 15 of the following 20 binocular targets. Check off each as you spot them. Seen # Object Const. Type* RA Dec Mag Size Nickname 1. M13 Her GC 16 41.7 +36 28 5.9 16' Great Hercules Globular 2. M57 Lyr PN 18 53.6 +33 02 9.7 86"x62" Ring Nebula 3. Collinder 399 Vul AS 19 25.4 +20 11 3.6 60' Coathanger/Brocchi’s Cluster 3.1 4. Albireo Cyg Dbl 19 30.7 +27 57 35” Color Contrasting Double 5.1 5. M27 Vul PN 19 59.6 +22 43 8.1 8’x6’ Dumbbell Nebula 6. NGC 6992 Cyg SNR 20 56.4 +31 43 - 60'x8 Veil Nebula (east) 7. NGC 7000 Cyg BN 20 58.8 +44 20 - 120'x100' North America Nebula 8. M15 Peg GC 21 30.0 +12 10 7.5 12’ Great Pegasus Cluster 9. M39 Cyg OC 21 32.2 +48 26 4.6 32' 10. Barnard 168 Cyg DN 21 53.2 +47 12 - 100'x10' West of Cocoon Nebula 11. IC 5146 Cyg BN/OC 21 53.5 +47 16 - 12'x12' Cocoon Nebula 12. M110 And Gx 00 40.4 +41 41 10 17’x10’ 13. M32 And Gx 00 42.8 +40 52 10 8’x6’ 14. M31 And Gx 00 42.8 +41 16 4.5 178’ Andromeda Galaxy 15. NGC 457 Cas OC 01 19.1 +58 20 6.4 13’ Owl Cluster/ET Cluster 16. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
1 the XMM-NEWTON SURVEY of the TAURUS MOLECULAR CLOUD: ACCRETION, JETS, and FLUORESCENCE M. Audard1, Manuel Güdel2, Kevin Brigg
1 THE XMM-NEWTON SURVEY OF THE TAURUS MOLECULAR CLOUD: ACCRETION, JETS, AND FLUORESCENCE M. Audard1, Manuel G¨udel2, Kevin Briggs2, and the XEST Team3 1Columbia Astrophysics Laboratory, 550 West 120th Street, NC 5247, New York, NY 10027, USA 2Paul Scherrer Institut, 5232 Villigen PSI, Switzerland ABSTRACT 1031 The Taurus Molecular Cloud (TMC) is one of the best studied star forming regions. It is close (140 pc) and represents the mode of isolated, non-clustered star for- mation. XMM-Newton has surveyed the richer 5 square degrees of the TMC in X-rays and has obtained high- 30 quality photometric and spectroscopic data of young stars 10 LX and brown dwarfs in their early stages of formation. We present results of the X-ray Emission Survey of TMC (XEST) on the following topics: i) Accretion. The ori- gin of X-rays in young, accreting stars is controversial, as accretion appears to be the dominant emission mech- 1029 anism in some classical T Tauri stars, whereas magnetic activity is the preferred explanation for others. The TMC 10-10 10-9 10-8 10-7 10-6 10-5 Mdot contains several accreting stars whose spectra help us un- derstand the importance of accretion for the production of X-rays. ii) Jets. Young, accreting stars display jets detected in the optical, near-infrared, and radio domains. There is now evidencethat jets are also detected in X-rays in some TMC targets. iii) Fluorescence. The detection of 7.5 an emission feature at 6.4 keV indicates that fluorescence of Fe in a cool environment,e.g., the accretion disk, takes place due to photoionization by hard X-rays or collisions logTav with electron beams. -
Statistics of Superimposed Flares in the Taurus Molecular Cloud
A&A 468, 477–484 (2007) Astronomy DOI: 10.1051/0004-6361:20066551 & c ESO 2007 Astrophysics The XMM-Newton extended survey of the Taurus molecular cloud Special feature Statistics of superimposed flares in the Taurus molecular cloud K. Arzner1, M. Güdel1, K. Briggs1, A. Telleschi1, and M. Audard2, 1 Paul Scherrer Institut, CH 5232 Villigen, Switzerland e-mail: [email protected] 2 Columbia Astrophysics Laboratory, 550 West 120th St., MC 5247, New York, NY 10027, USA Received 12 October 2006 / Accepted 19 February 2007 ABSTRACT Context. Stochastically occurring flares provide a possible mechanism of coronal heating in magnetically active stars such as T Tauri objects in star-forming regions. Aims. We investigate the statistics of stellar X-ray light curves from the XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST). Methods. To this end, the light curve is modeled as superimposed flares occurring at random times and with random amplitudes. The flare shape is estimated non-parametrically from the observations, while the flare amplitude distribution is modeled as a truncated power law, and the flare times are assumed as uniformly distributed. From these model assumptions, predictions on the binned counts are derived and compared with the observations. Results. From a sample of 22 XEST observations matching the above model assumptions we find that the majority of cases have flare amplitude distributions with slopes steeper than two. This favours the role of small flares in coronal heating for 5 targets, of which, however, 4 are foreground or background main-sequence stars. Key words. methods: statistical – stars: coronae – stars: pre-main sequence – X-rays: stars 1. -
Instruction Manual Meade Instruments Corporation
Instruction Manual 7" LX200 Maksutov-Cassegrain Telescope 8", 10", and 12" LX200 Schmidt-Cassegrain Telescopes Meade Instruments Corporation NOTE: Instructions for the use of optional accessories are not included in this manual. For details in this regard, see the Meade General Catalog. (2) (1) (1) (2) Ray (2) 1/2° Ray (1) 8.218" (2) 8.016" (1) 8.0" Secondary 8.0" Mirror Focal Plane Secondary Primary Baffle Tube Baffle Field Stops Correcting Primary Mirror Plate The Meade Schmidt-Cassegrain Optical System (Diagram not to scale) In the Schmidt-Cassegrain design of the Meade 8", 10", and 12" models, light enters from the right, passes through a thin lens with 2-sided aspheric correction (“correcting plate”), proceeds to a spherical primary mirror, and then to a convex aspheric secondary mirror. The convex secondary mirror multiplies the effective focal length of the primary mirror and results in a focus at the focal plane, with light passing through a central perforation in the primary mirror. The 8", 10", and 12" models include oversize 8.25", 10.375" and 12.375" primary mirrors, respectively, yielding fully illuminated fields- of-view significantly wider than is possible with standard-size primary mirrors. Note that light ray (2) in the figure would be lost entirely, except for the oversize primary. It is this phenomenon which results in Meade 8", 10", and 12" Schmidt-Cassegrains having off-axis field illuminations 10% greater, aperture-for-aperture, than other Schmidt-Cassegrains utilizing standard-size primary mirrors. The optical design of the 4" Model 2045D is almost identical but does not include an oversize primary, since the effect in this case is small. -
List of Bright Nebulae Primary I.D. Alternate I.D. Nickname
List of Bright Nebulae Alternate Primary I.D. Nickname I.D. NGC 281 IC 1590 Pac Man Neb LBN 619 Sh 2-183 IC 59, IC 63 Sh2-285 Gamma Cas Nebula Sh 2-185 NGC 896 LBN 645 IC 1795, IC 1805 Melotte 15 Heart Nebula IC 848 Soul Nebula/Baby Nebula vdB14 BD+59 660 NGC 1333 Embryo Neb vdB15 BD+58 607 GK-N1901 MCG+7-8-22 Nova Persei 1901 DG 19 IC 348 LBN 758 vdB 20 Electra Neb. vdB21 BD+23 516 Maia Nebula vdB22 BD+23 522 Merope Neb. vdB23 BD+23 541 Alcyone Neb. IC 353 NGC 1499 California Nebula NGC 1491 Fossil Footprint Neb IC 360 LBN 786 NGC 1554-55 Hind’s Nebula -Struve’s Lost Nebula LBN 896 Sh 2-210 NGC 1579 Northern Trifid Nebula NGC 1624 G156.2+05.7 G160.9+02.6 IC 2118 Witch Head Nebula LBN 991 LBN 945 IC 405 Caldwell 31 Flaming Star Nebula NGC 1931 LBN 1001 NGC 1952 M 1 Crab Nebula Sh 2-264 Lambda Orionis N NGC 1973, 1975, Running Man Nebula 1977 NGC 1976, 1982 M 42, M 43 Orion Nebula NGC 1990 Epsilon Orionis Neb NGC 1999 Rubber Stamp Neb NGC 2070 Caldwell 103 Tarantula Nebula Sh2-240 Simeis 147 IC 425 IC 434 Horsehead Nebula (surrounds dark nebula) Sh 2-218 LBN 962 NGC 2023-24 Flame Nebula LBN 1010 NGC 2068, 2071 M 78 SH 2 276 Barnard’s Loop NGC 2149 NGC 2174 Monkey Head Nebula IC 2162 Ced 72 IC 443 LBN 844 Jellyfish Nebula Sh2-249 IC 2169 Ced 78 NGC Caldwell 49 Rosette Nebula 2237,38,39,2246 LBN 943 Sh 2-280 SNR205.6- G205.5+00.5 Monoceros Nebula 00.1 NGC 2261 Caldwell 46 Hubble’s Var. -
New Infrared Star Clusters and Candidates in the Galaxy Detected with 2MASS
Astronomy & Astrophysics manuscript no. (will be inserted by hand later) New infrared star clusters and candidates in the Galaxy detected with 2MASS C.M. Dutra1,2 and E. Bica1 1 Universidade Federal do Rio Grande do Sul, IF, CP 15051, Porto Alegre 91501–970, RS, Brazil 2 Instituto Astronomico e Geofisico da USP, CP 3386, S˜ao Paulo 01060-970, SP, Brazil Received ; accepted Abstract. A sample of 42 new infrared star clusters, stellar groups and candidates was found throughout the Galaxy in the 2MASS J, H and especially KS Atlases. In the Cygnus X region 19 new clusters, stellar groups and candidates were found as compared to 6 such objects in the previous literature. Colour-Magnitude Diagrams using the 2MASS Point Source Catalogue provided preliminary distance estimates in the range 1.0 < d⊙ < 1.8 kpc for 7 Cygnus X clusters. Towards the central parts of the Galaxy 7 new IR clusters and candidates were found as compared to 61 previous objects. A search for prominent dark nebulae in KS was also carried out in the central bulge area. We report 5 dark nebulae, 2 of them are candidates for molecular clouds able to generate massive star clusters near the Nucleus, such as the Arches and Quintuplet clusters. Key words. (Galaxy): open clusters and associations: individual 1. Introduction objects. Despite a systematic search for faint clusters on the Palomar plates like that generating the Berkeley clus- The digital Two Micron All Sky Survey (2MASS) ters (Setteducati & Weaver 1962), or the individual lists infrared atlas (Skrutskie et al. 1997 – web inter- which generated the ESO catalogue (Lauberts 1982 and face http://www.ipac.caltech.edu/2mass/) can provide a references therein), until quite recently new star clusters wealth of new objects for future studies with large tele- and candidates both on the Palomar and ESO/SERC scopes, a role similar to that played in the optical by the Schmidt plates could still be found (e.g. -
Meeting Program
A A S MEETING PROGRAM 211TH MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY WITH THE HIGH ENERGY ASTROPHYSICS DIVISION (HEAD) AND THE HISTORICAL ASTRONOMY DIVISION (HAD) 7-11 JANUARY 2008 AUSTIN, TX All scientific session will be held at the: Austin Convention Center COUNCIL .......................... 2 500 East Cesar Chavez St. Austin, TX 78701 EXHIBITS ........................... 4 FURTHER IN GRATITUDE INFORMATION ............... 6 AAS Paper Sorters SCHEDULE ....................... 7 Rachel Akeson, David Bartlett, Elizabeth Barton, SUNDAY ........................17 Joan Centrella, Jun Cui, Susana Deustua, Tapasi Ghosh, Jennifer Grier, Joe Hahn, Hugh Harris, MONDAY .......................21 Chryssa Kouveliotou, John Martin, Kevin Marvel, Kristen Menou, Brian Patten, Robert Quimby, Chris Springob, Joe Tenn, Dirk Terrell, Dave TUESDAY .......................25 Thompson, Liese van Zee, and Amy Winebarger WEDNESDAY ................77 We would like to thank the THURSDAY ................. 143 following sponsors: FRIDAY ......................... 203 Elsevier Northrop Grumman SATURDAY .................. 241 Lockheed Martin The TABASGO Foundation AUTHOR INDEX ........ 242 AAS COUNCIL J. Craig Wheeler Univ. of Texas President (6/2006-6/2008) John P. Huchra Harvard-Smithsonian, President-Elect CfA (6/2007-6/2008) Paul Vanden Bout NRAO Vice-President (6/2005-6/2008) Robert W. O’Connell Univ. of Virginia Vice-President (6/2006-6/2009) Lee W. Hartman Univ. of Michigan Vice-President (6/2007-6/2010) John Graham CIW Secretary (6/2004-6/2010) OFFICERS Hervey (Peter) STScI Treasurer Stockman (6/2005-6/2008) Timothy F. Slater Univ. of Arizona Education Officer (6/2006-6/2009) Mike A’Hearn Univ. of Maryland Pub. Board Chair (6/2005-6/2008) Kevin Marvel AAS Executive Officer (6/2006-Present) Gary J. Ferland Univ. of Kentucky (6/2007-6/2008) Suzanne Hawley Univ. -
Astrophysical Studies of Extrasolar Planetary Systems Using Infrared Interferometric Techniques Olivier Absil
Astrophysical studies of extrasolar planetary systems using infrared interferometric techniques Olivier Absil To cite this version: Olivier Absil. Astrophysical studies of extrasolar planetary systems using infrared interferometric techniques. Astrophysics [astro-ph]. Université de Liège, 2006. English. tel-00124720 HAL Id: tel-00124720 https://tel.archives-ouvertes.fr/tel-00124720 Submitted on 15 Jan 2007 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Facult´edes Sciences D´epartement d’Astrophysique, G´eophysique et Oc´eanographie Astrophysical studies of extrasolar planetary systems using infrared interferometric techniques THESE` pr´esent´eepour l’obtention du diplˆomede Docteur en Sciences par Olivier Absil Soutenue publiquement le 17 mars 2006 devant le Jury compos´ede : Pr´esident: Pr. Jean-Pierre Swings Directeur de th`ese: Pr. Jean Surdej Examinateurs : Dr. Vincent Coude´ du Foresto Dr. Philippe Gondoin Pr. Jacques Henrard Pr. Claude Jamar Dr. Fabien Malbet Institut d’Astrophysique et de G´eophysique de Li`ege Mis en page avec la classe thloria. i Acknowledgments First and foremost, I want to express my deepest gratitude to my advisor, Professor Jean Surdej. I am forever indebted to him for striking my interest in interferometry back in my undergraduate student years; for introducing me to the world of scientific research and fostering so many international collaborations; for helping me put this work in perspective when I needed it most; and for guiding my steps, from the supervision of diploma thesis to the conclusion of my PhD studies.