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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. -
The AAVSO DSLR Observing Manual
The AAVSO DSLR Observing Manual AAVSO 49 Bay State Road Cambridge, MA 02138 email: [email protected] Version 1.2 Copyright 2014 AAVSO Foreword This manual is a basic introduction and guide to using a DSLR camera to make variable star observations. The target audience is first-time beginner to intermediate level DSLR observers, although many advanced observers may find the content contained herein useful. The AAVSO DSLR Observing Manual was inspired by the great interest in DSLR photometry witnessed during the AAVSO’s Citizen Sky program. Consumer-grade imaging devices are rapidly evolving, so we have elected to write this manual to be as general as possible and move the software and camera-specific topics to the AAVSO DSLR forums. If you find an area where this document could use improvement, please let us know. Please send any feedback or suggestions to [email protected]. Most of the content for these chapters was written during the third Citizen Sky workshop during March 22-24, 2013 at the AAVSO. The persons responsible for creation of most of the content in the chapters are: Chapter 1 (Introduction): Colin Littlefield, Paul Norris, Richard (Doc) Kinne, Matthew Templeton Chapter 2 (Equipment overview): Roger Pieri, Rebecca Jackson, Michael Brewster, Matthew Templeton Chapter 3 (Software overview): Mark Blackford, Heinz-Bernd Eggenstein, Martin Connors, Ian Doktor Chapters 4 & 5 (Image acquisition and processing): Robert Buchheim, Donald Collins, Tim Hager, Bob Manske, Matthew Templeton Chapter 6 (Transformation): Brian Kloppenborg, Arne Henden Chapter 7 (Observing program): Des Loughney, Mike Simonsen, Todd Brown Various figures: Paul Valleli Clear skies, and Good Observing! Arne Henden, Director Rebecca Turner, Operations Director Brian Kloppenborg, Editor Matthew Templeton, Science Director Elizabeth Waagen, Senior Technical Assistant American Association of Variable Star Observers Cambridge, Massachusetts June 2014 i Index 1. -
Stable and Unstable Accretion in the Classical T Tauri Stars IM Lup and RU Lup As Observed by MOST
Mon. Not. R. Astron. Soc. 000, 000–000 (2015) Printed 27 August 2018 (MN LATEX style file v2.2) Stable and unstable accretion in the classical T Tauri stars IM Lup and RU Lup as observed by MOST Michal Siwak1⋆, Waldemar Ogloza1, Slavek M. Rucinski2, Anthony F. J. Moffat3, Jaymie M. Matthews4, Chris Cameron5, David B. Guenther6, Rainer Kuschnig4,9, Jason F. Rowe7, Dimitar Sasselov8, Werner W. Weiss9 1Mount Suhora Astronomical Observatory, Cracov Pedagogical University, ul. Podchorazych 2, 30-084 Cracov, Poland 2Department of Astronomy and Astrophysics, University of Toronto, 50 St. George St., Toronto, Ontario, M5S 3H4, Canada 3D´epartment de Physique, Universit´ede Montr´eal, C.P.6128, Succursale: Centre-Ville, Montr´eal, QC, H3C 3J7, Canada 4Department of Physics & Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, B.C., V6T 1Z1, Canada 5Department of Mathematics, Physics & Geology, Cape Breton University, 1250 Grand Lake Road, Sydney,NS, B1P 6L2, Canada 6Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Marys University, Halifax, N.S., B3H 3C3, Canada 7NASA Ames Research Center, Moffett Field, CA 94035, USA 8Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 9Universit¨at Wien, Institut f¨ur Astrophysik, T¨urkenschanzstrasse 17, A-1180 Wien, Austria Accepted 2015 December 2; Received 2015 November 11; in original form 2015 September 6 ABSTRACT Results of the time variability monitoring of the two classical T Tauri stars, RU Lup and IM Lup, are presented. Three photometric data sets were utilised: (1) simultaneous (same field) MOST satellite observations over four weeks in each of the years 2012 and 2013, (2) multicolour observations at the SAAO in April – May of 2013, (3) archival V - filter ASAS data for nine seasons, 2001 – 2009. -
Pos(MULTIF2017)001
Multifrequency Astrophysics (A pillar of an interdisciplinary approach for the knowledge of the physics of our Universe) ∗† Franco Giovannelli PoS(MULTIF2017)001 INAF - Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere, 100, 00133 Roma, Italy E-mail: [email protected] Lola Sabau-Graziati INTA- Dpt. Cargas Utiles y Ciencias del Espacio, C/ra de Ajalvir, Km 4 - E28850 Torrejón de Ardoz, Madrid, Spain E-mail: [email protected] We will discuss the importance of the "Multifrequency Astrophysics" as a pillar of an interdis- ciplinary approach for the knowledge of the physics of our Universe. Indeed, as largely demon- strated in the last decades, only with the multifrequency observations of cosmic sources it is possible to get near the whole behaviour of a source and then to approach the physics governing the phenomena that originate such a behaviour. In spite of this, a multidisciplinary approach in the study of each kind of phenomenon occurring in each kind of cosmic source is even more pow- erful than a simple "astrophysical approach". A clear example of a multidisciplinary approach is that of "The Bridge between the Big Bang and Biology". This bridge can be described by using the competences of astrophysicists, planetary physicists, atmospheric physicists, geophysicists, volcanologists, biophysicists, biochemists, and astrobiophysicists. The unification of such com- petences can provide the intellectual framework that will better enable an understanding of the physics governing the formation and structure of cosmic objects, apparently uncorrelated with one another, that on the contrary constitute the steps necessary for life (e.g. Giovannelli, 2001). -
Tetrahedral Hydrocarbon Nanoparticles in Space: X-Ray Spectra
Mon. Not. R. Astron. Soc. 000, 1–7 (2018) Printed 15 October 2018 (MN LATEX style file v2.2) Tetrahedral hydrocarbon nanoparticles in space: X-ray spectra G. Bilalbegovic´1, A. Maksimovic´2, L. A. Valencic3;4 1Department of Physics, Faculty of Science, University of Zagreb, Bijenickaˇ cesta 32, 10000 Zagreb, Croatia 2Center of Excellence for Advanced Materials and Sensing Devices, Rudjer Boskoviˇ c´ Institute, Bijenickaˇ cesta 54, 10000 Zagreb, Croatia 3NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 4The Johns Hopkins University, Department of Physics & Astronomy, 366 Bloomberg Center, 3400 N. Charles St., Baltimore, MD 21218, USA 15 October 2018 ABSTRACT It has been proposed, or confirmed, that diamond nanoparticles exist in various environ- ments in space: close to active galactic nuclei, in the vicinity of supernovae and pulsars, in the interior of several planets in the Solar system, in carbon planets and other exoplanets, carbon- rich stars, meteorites, in X-ray active Herbig Ae/Be stars, and in the interstellar medium. Using density functional theory methods we calculate the carbon K-edge X-ray absorption spectrum of two large tetrahedral nanodiamonds: C26H32 and C51H52. We also study and test our methods on the astrophysical molecule CH4, the smallest C-H tetrahedral structure. A possible detection of nanodiamonds from X-ray spectra by future telescopes, such as the project Arcus, is proposed. Simulated spectra of the diffuse interstellar medium using Cyg X-2 as a source show that nanodiamonds studied in this work can be detected by Arcus, a high resolution X-ray spectrometer mission selected by NASA for a Phase A concept study. -
The Loopy UV Line Profiles of RU Lupi: Accretion, Outflows, and Fluorescence
submitted to AJ The loopy UV line profiles of RU Lupi: accretion, outflows, and fluorescence Gregory J. Herczeg1, Frederick M. Walter2, Jeffrey L. Linsky1, G¨osta F. Gahm3, David R. Ardila4, Alexander Brown5, Christopher M. Johns-Krull6, Michal Simon2, Jeff A. Valenti7 ABSTRACT We present far-ultraviolet spectra of the classical T Tauri star RU Lupi covering the 912–1710 A˚ spectral range, as observed by the HST /STIS and FUSE satellites. We use these spectra, which are rich in emission and absorption lines, to probe both the accreting and outflowing gas. Absorption in the Lyα profile constrains the extinction to AV ∼ 0.07 mag, which we confirm with other diagnostics. We estimate a mass −8 −1 accretion rate of (5 ± 2) × 10 M⊙ yr using the optical-NUV accretion continuum. The accreting gas is also detected in bright, broad lines of C IV, Si IV, and N V, which all show complex structures across the line profile. Many other emission lines, including those of H2 and Fe II, are pumped by Lyα. RU Lupi’s spectrum varies significantly in the FUV; our STIS observations occurred when RU Lupi was brighter than several other observations in the FUV, possibly due to a high mass accretion rate. Subject headings: accretion, accretion disks — circumstellar matter — line: iden- tification — stars: individual (RU Lupi) — stars: pre-main sequence — ultraviolet: stars 1. INTRODUCTION Classical T Tauri stars (CTTSs) are likely prototypes of the young Sun when it was accreting arXiv:astro-ph/0504654v1 29 Apr 2005 material from its circumstellar disk. In the standard -
Where Are the Hot Ion Lines in Classical T Tauri Stars Formed?
Accretion, winds and jets: High-energy emission from young stellar objects Dissertation zur Erlangung des Doktorgrades des Departments Physik der Universit¨at Hamburg vorgelegt von Hans Moritz G¨unther aus Hamburg Hamburg 2009 ii Gutachter der Dissertation: Prof. Dr. J. H. M. M. Schmitt Prof. Dr. E. Feigelson Gutachter der Disputation: Prof. Dr. P. H. Hauschildt Prof. Dr. G. Wiedemann Datum der Disputation: 13.03.2009 Vorsitzender des Pr¨ufungsausschusses: Dr. R. Baade Vorsitzender des Promotionsausschusses: Prof. Dr. R. Klanner Dekan der MIN Fakult¨at: Prof. Dr. A. Fr¨uhwald (bis 28.02.2009) Prof. Dr. H. Graener (ab 01.03.2009) iii Zusammenfassung Sterne entstehen durch Gravitationsinstabilit¨aten in molekularen Wolken. Wegen der Erhaltung des Drehimpulses geschieht der Kollaps nicht sph¨arisch, sondern das Material f¨allt zun¨achst auf eine Akkretionsscheibe zusammen. In dieser Doktorarbeit wird hochenergetische Strahlung von Sternen untersucht, die noch aktiv Material von ihrer Scheibe akkretieren, aber nicht mehr von einer Staub- und Gash¨ulle verdeckt sind. In dieser Phase nennt man Sterne der Spektraltypen A und B Herbig Ae/Be (HAeBe) Sterne, alle sp¨ateren Sterne heißen klassische T Tauri Sterne (CTTS); eigentlich werden beide Typen ¨uber spektroskopische Merkmale definiert, aber diese fallen mit den hier genannten Entwicklungsstadien zusammen. In dieser Arbeit werden CTTS und HAeBes mit hochaufl¨osender Spektroskopie im R¨ontgen- und UV-Bereich untersucht und Simulationen f¨ur diese Stadien gezeigt. F¨ur zwei Sterne werden R¨ontgenspektren reduziert und vorgestellt: Der CTTS V4046 Sgr wurde mit Chandra f¨ur 100 ks beobachtet. Die Lichtkurve dieser Beobachtung zeigt einen Flare und die Triplets der He Isosequenz (Si xiii, Ne ix und O vii) deuten auf hohe Dichten im emittierenden Plasma hin. -
Thomas J. Maccarone Texas Tech
Thomas J. Maccarone PERSONAL Born August 26, 1974, Haverhill, Massachusetts, USA INFORMATION US Citizen CONTACT Department of Physics & Astronomy Voice: +1-806-742-3778 INFORMATION Texas Tech University Lubbock TX 79409 E-mail: [email protected] RESEARCH Compact object populations, especially in globular clusters; accretion and ejection physics; time INTERESTS series analysis methodology PROFESSIONAL Texas Tech University EXPERIENCE Lubbock, Texas Presidential Research Excellence Professor, Department of Physics & Astronomy August 2018-present Professor, Department of Physics & Astronomy August 2017- August 2018 Associate Professor, Department of Physics January 2013 - August 2017 University of Southampton Southampton, UK Lecturer, then Reader, School of Physics and Astronomy July 2005-December 2012 University of Amsterdam Amsterdam, The Netherlands Postdoctoral researcher May 2003 - June 2005 SISSA (Scuola Internazionale di Studi Avanazti/International School for Advanced Studies) Trieste, Italy Postdoctoral researcher November 2001 - April 2003 Yale University New Haven, Connecticut USA Research Assistant May 1997 - August 2001 Jet Propulsion Laboratory Pasadena, California USA Summer Undergraduate Research Fellow June 1994 - August 1994 EDUCATION Yale University, New Haven, CT USA Department of Astronomy Ph.D., December 2001 Dissertation Title: “Constraints on Black Hole Emission Mechanisms” Advisor: Paolo S. Coppi M.S., M.Phil., Astronomy, May 1999 California Institute of Technology, Pasadena, California USA B.S., Physics, June, 1996 HONORS AND Integrated Scholar, Designation from Texas Tech for faculty who integrate teaching, research and AWARDS service activities together, 2020 Professor of the Year Award, Texas Tech Society of Physics Students, 2017, 2019 Dirk Brouwer Prize from Yale University for “a contribution of unusual merit to any branch of astronomy,” 2003 Harry A. -
Mètodes De Detecció I Anàlisi D'exoplanetes
MÈTODES DE DETECCIÓ I ANÀLISI D’EXOPLANETES Rubén Soussé Villa 2n de Batxillerat Tutora: Dolors Romero IES XXV Olimpíada 13/1/2011 Mètodes de detecció i anàlisi d’exoplanetes . Índex - Introducció ............................................................................................. 5 [ Marc Teòric ] 1. L’Univers ............................................................................................... 6 1.1 Les estrelles .................................................................................. 6 1.1.1 Vida de les estrelles .............................................................. 7 1.1.2 Classes espectrals .................................................................9 1.1.3 Magnitud ........................................................................... 9 1.2 Sistemes planetaris: El Sistema Solar .............................................. 10 1.2.1 Formació ......................................................................... 11 1.2.2 Planetes .......................................................................... 13 2. Planetes extrasolars ............................................................................ 19 2.1 Denominació .............................................................................. 19 2.2 Història dels exoplanetes .............................................................. 20 2.3 Mètodes per detectar-los i saber-ne les característiques ..................... 26 2.3.1 Oscil·lació Doppler ........................................................... 27 2.3.2 Trànsits -
The Sun: the First 4.6 Gyr Color of Frederick M
ado. The Sun: The First 4.6 Gyr Color of Frederick M. Walter1 Abstract. I present an overview of some observations of young and active solar- University like stars with non-solar-like characteristics. I ask whether the solar anal- ogy can be extrapolated to explain very active stars without violating 2003 simple geometrical constraints. Is a young and active star merely an ex- treme version of today's Sun, with the same atmospheric structures but Sun, with ¯lling factors reaching (or exceeding) unity? In light of evidence for large scale quasi-dipolar magnetic topologies on the young and restless The stars, maybe it is time to rethink our paradigms. & There is something fascinating about science. One gets such whole- Systems, sale returns of conjecture out of such a trifling investment of fact. Mark Twain ¡¡ Life on the Mississippi lar Stel Despite appearances, this is not a review of the evolution of stellar magnetic activity. It is, rather, a set of variations on a theme: the solar analogy, as a guide to the interpretation of the coronae and chromospheres of the most active Stars, stars, needs to be reconsidered. You may alternatively consider this an extended ol introduction and overview, designed to set the scene for the contributed papers Co in this session. To that end, making no pretense of being complete or unbiased, on I present a series of observations focussed on non-solar-like properties in active cool stars, intended to provoke discussion. Our paradigm has long been that stellar magnetic activity is just like solar magnetic activity, only ever-so-much-more-so. -
2013 Version
Citizen Science with Variable Stars Brought to you by the AAVSO, Astronomers without Borders, the National Science Foundation and Your Universe Astronomers need your help! Many bright stars change in brightness all the time and for many different reasons. Some stars are too bright for professionals to CitizenSky is a collaboration of the look at with most large telescopes. So, we American Association of need your help to watch these stars as they Variable Star Observers (AAVSO), the University of dim and brighten over the next several years. Denver, the Adler Planetarium, the Johns Hopkins University and the California Academies of This guide will help you find these bright Science with support from the National Science Foundation. stars, measure their brightness and then submit the measurements to assist professional astronomers. Participate in one of the largest and longest running citizen science projects in history! Thousands of people just like you are helping o ut. Astronomers need large numbers of people to get the amount of precision they need to do their research. You are the key. Header artwork is reproduced with permission from Sky & Telescope magazine (www.skyandtelescope.com) Betelgeuse – Alpha Orionis From the city or country sky, from almost any part of the world, the majestic figure of Orion dominates the night sky with his belt, sword, and club. Low and to the right is the great red pulsating supergiant, Betelgeuse (alpha Orionis). Recently acquiring fame for being the first star to have its atmosphere directly imaged (shown below), alpha Orionis has captivated observers' attention for centuries. At minimum brightness, as in 1927 and 1941, its magnitude may drop below 1.2. -
Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al
Noname manuscript No. (will be inserted by the editor) Weighing stars from birth to death: mass determination methods across the HRD Aldo Serenelli · Achim Weiss · Conny Aerts · George C. Angelou · David Baroch · Nate Bastian · Paul G. Beck · Maria Bergemann · Joachim M. Bestenlehner · Ian Czekala · Nancy Elias-Rosa · Ana Escorza · Vincent Van Eylen · Diane K. Feuillet · Davide Gandolfi · Mark Gieles · L´eoGirardi · Yveline Lebreton · Nicolas Lodieu · Marie Martig · Marcelo M. Miller Bertolami · Joey S.G. Mombarg · Juan Carlos Morales · Andr´esMoya · Benard Nsamba · KreˇsimirPavlovski · May G. Pedersen · Ignasi Ribas · Fabian R.N. Schneider · Victor Silva Aguirre · Keivan G. Stassun · Eline Tolstoy · Pier-Emmanuel Tremblay · Konstanze Zwintz Received: date / Accepted: date A. Serenelli Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E- 08193, Spain and Institut d'Estudis Espacials de Catalunya (IEEC), Carrer Gran Capita 2, Barcelona, E-08034, Spain E-mail: [email protected] A. Weiss Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany C. Aerts Institute of Astronomy, Department of Physics & Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium and Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands G.C. Angelou Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany D. Baroch J. C. Morales I. Ribas Institute of· Space Sciences· (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E-08193, arXiv:2006.10868v2 [astro-ph.SR] 9 Apr 2021 Spain and Institut d'Estudis Espacials de Catalunya (IEEC), C/Gran Capit`a2-4, E-08034 2 Serenelli, Weiss, Aerts et al.