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Stars and Their Variability, Observed from Space

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Stars and their variability observed from space C. Neiner, W. W. Weiss, D. Baade, R. E. Griffin, C. C. Lovekin, A. F. J. Moffat (eds) Proceedings of the conference Stars and their variability, observed from space held in Vienna on August 19-23, 2019 Credit: University of Vienna © Stars from Space ii Stars and their variability, observed from space Contents i Table of contents i Preface ix List of participants xi Introduction 1 The Space Photometry Revolution F. Kerschbaum 3 Putting stars into boxes R. E. Griffin 5 Parameter space and pattern 9 Gaia’s revolution in stellar variability L. Eyer, L. Rimoldini, L. Rohrbasser, B. Holl, M. Audard, D.W. Evans, P. Garcia-Lario, P. Gavras, G. Clementini, S. T. Hodgkin, et al. 11 What we can learn from constant stars, and what does constant mean? E. Paunzen, J. Janík, J. Krtička, Z. Mikulášek, and M. Zejda 19 Pre-TESS observations of pulsating white dwarf stars at Konkoly Observatory Zs. Bognár, Cs. Kalup, and Á. Sódor 25 A pre-main sequence variability classifier for TESS M. Müllner, and K. Zwintz 27 Classification of variable stars D. Tarczay-Nehéz, R. Szabó, and Z. Szeleczky 29 Pulsation 33 The demystification of classical Be stars through space photometry D. Baade, and T. Rivinius 35 Potential and challenges of pre-main sequence asteroseismology K. Zwintz 39 Observations of internal structures of low-mass main-sequence stars and red giants S. Hekker 45 What physics is missing in theoretical models of high-mass stars: new insights from asteroseismology D. M. Bowman 53 Cepheids under the magnifying glass − not so simple, after all! R. I. Anderson 61 Asteroseismology of Rapidly Rotating Stars with Acoustic Modes D. R. Reese 67 The BRITE-SONG of Aldebaran – stellar music in three voices P. G. Beck, R. Kuschnig, G. Houdek, T. Kallinger, W. W. Weiss, P. L. Palle, F. Grundahl, A. Hatzes, H. Parviainen, C. Allende Prieto, et al. 75 ii Stars and their variability, observed from space The complex asteroseismology of SX Phoenicis J. Daszyńska-Daszkiewicz, P. Walczak, A. Pamyatnykh, W. Szewczuk, and W. Dziembowski 81 Modelling Long-Period Variables in the Gaia Era M. Trabucchi, T. Lebzelter, N. Mowlavi, P. R. Wood, P. Marigo, G. Pastorelli, and I. Lecoeur-Taïbi 87 The planet-host pulsating star HR 8799 as seen by BRITE Á. Sódor, and Zs. Bognár 91 The non-radial pulsation pattern of the Algol star RZ Cas H. Lehmann, F. Pertermann, V. Tsymbal, A. Tkachenko, and D. E. Mkrtichian 93 Pre-main Sequence Gravity-Mode Pulsators in K2 L. Ketzer, and K. Zwintz 95 Asteroseismology of the β Cen System C. Lovekin, and J. Tompkins 99 The prototype star γ Doradus observed by TESS S. Christophe, V. Antoci, E. Brunsden, R.-M. Ouazzani, and S.J.A.J. Salmon 101 The existence of hot γ Doradus and A–F-type hybrid stars F. Kahraman Aliçavuş, E. Poretti, G. Catanzaro, B. Smalley, E. Niemczura, M. Rainer, and G. Handler 103 Effect of the magnetic field on period spacings of gravity modes in rapidly rotating stars V. Prat, S. Mathis, B. Buysschaert, J. Van Beeck, D. M. Bowman, C. Aerts, and C. Neiner 105 Dynamical Mass of a Type II Cepheid and a disk around its Be star companion B. Pilecki 107 Galactic Red Supergiants in Gaia DR2 M. Messineo, and A.G.A. Brown 111 The pulsation spectrum of a mass-accreting component of AS Eri D. Mkrtichian, K. Gunsriwiwat, C. Engelbrecht, N. A-thano, H. Lehmann, P. Lampens, J. Matthews, E. Rodriguez, and A. Kusakin 113 Cepheids Near and Far D. Tarczay-Nehéz, L. Szabados, and Z. Dencs 115 Science with BRITE-Constellation at the University of Innsbruck K. Zwintz, R. Kuschnig, C. Arnold, F. Brüser, M. J. Dornacher, S. Gössl, A. Ivanov, M. Mayerl, M. Müller, M. Müllner, et al. 119 Long-term BRITE and SMEI space photometry of γ Cas (B0.5 IVe) C. C. Borre, D. Baade, A. Pigulski, A. Weiss, T. Rivinius, and The BRITE Team 121 Variability other than pulsation 123 CHEOPS & stars (& asteroseismology) S. Barceló Forteza, A. Moya, A. Bonfanti, S.J.A.J. Salmon, V. Van Grootel, and D. Barrado 125 Early-type magnetic stars: The rotation challenge G. Mathys 131 Be star variability as seen from ground-based and space photometry J. Labadie-Bartz, and A. C. Carciofi 137 Contents iii BRITEness variations of the BRITEst hot stars T. Ramiaramanantsoa, A. F. and J. Moffat 147 Shine BRITE: shedding light on stellar variability through advanced models D. Fabbian, F. Kupka, D. Krüger, N. M. Kostogryz, and N. Piskunov 155 Rieger-type periodicity in the activity of solar-type stars E. Gurgenashvili, T.V. Zaqarashvili, V. Kukhianidze, A. Reiners, and T. Reinhold 161 Superfast spectral variations of OBA stars A.A. Batrakov, A.F. Kholtygin, S. Hubrig, S. Fabrika, A.F. Valeev, and A.E. Kostenkov 163 Results of Light-Curves Analyses for the Dwarf Nova EX Dra I. Voloshina, and T. Khruzina 165 Instrinsic X-ray variability of O stars and Wolf-Rayet stars A.M.T. Pollock 167 Astronomical potential of satellite star trackers A.M.T. Pollock 169 EM Cep – an interesting Be star N. Kochiashvili, I. Kochiashvili, R. Natsvlishvili, S. Beradze, and M. Vardosanidze 171 Old and New observational Data for P Cygni S. Beradze, N.Kochiashvili, I.Kochiashvili, R.Natsvlishvili, and M.Vardosanidze 173 Discovery of the first Ap star in an eclipsing binary system M. Skarka, P. Kabáth, E. Paunzen, M. Mašek, J. Žák, and J. Janík 175 MOBSTER: Search for period evolution in Orion’s Magnetic B-type Stars M. E. Shultz, A. David-Uraz, J. Labadie-Bartz, Z. Mikulášek, and V. Petit 177 The strange case of HD 65987, a magnetic Bp star with two periods J. D. Landstreet, A. David-Uraz, O. Kochukhov, C. Neiner, P. Nelson, and G. Wade 181 Multi-Instrument Analysis of Gaia, Kepler K2, ASAS-SN, and ASAS Observations of Long-Period Variables E. Hartig, T. Lebzelter, and K.H. Hinkle 183 The imposter Be star HD 19818: superflares in a cool giant? J. Labadie-Bartz, and A. C. Carciofi 185 STEREO Observations of Be Stars D. Ozuyar, and L. Balona 189 Variability of Wolf-Rayet Stars through MOST(LY) BRITE Eyes G. Lenoir-Craig, N. St-Louis, A.F.J. Moffat, T. Ramiaramanantsoa, and H. Pablo 191 Simultaneous photometric and spectroscopic analysis of a new outburst of V1686 Cyg H.R. Andreasyan 193 Magnetic field measurements of Kepler Ap/CP2 stars I. I. Romanyuk, Z. Mikulášek, S. Hümmerich, I. Yakunin, A. Moiseeva, J. Janík, K. Bernhard, J. Krtička, E. Paunzen, M. Jagelka, et al. 197 Near-ultraviolet Variability in the Kepler Field E. Bertone, M. Sachkov, D. Olmedo, M. Olmedo, and M. Chavez 199 Modelling 201 iv Stars and their variability, observed from space Listening to the Heartbeat: Tidal Asteroseismology in Action Z. Guo 203 3D Hydrodynamical Simulations of Stellar Convection for Helio- and Asteroseismology F. Kupka 209 Challenges to modelling from ground-breaking new data of present/future space and ground facilities G. Clementini, M. Marconi, and A. Garofalo 215 Open problems in high-mass stellar evolution S. Ekström, G.Meynet, C. Georgy, R. Hirschi, A. Maeder, J. Groh, P. Eggenberger, and G. Buldgen 223 Internal stellar magnetic fields J. Fuller 229 Search for Quiet Stellar-mass Black Holes by Asteroseismology from Space H. Shibahashi, and S. J. Murphy 235 Accretion simulations of η Carinae and implications for the evolution of massive binaries A. Kashi 243 From the Sun to solar-like stars: how does the solar modelling problem affect our studies of solar-like oscillators? G. Buldgen, C. Pezzotti, M. Farnir, S.J.A.J. Salmon, and P. Eggenberger 249 Asteroseismic Binaries as non-Solar Mixing Length Calibrators M. Joyce 255 Unbiased seismic model fitting T. Kallinger 259 The relevance of partial ionization in the outer layers of F stars A. Brito, and I. Lopes 265 KIC 11971405 - the SPB star with the four asymptotic sequences of g modes W. Szewczuk, P. Walczak, and J. Daszyńska-Daszkiewicz 271 The slowly pulsating B-star 18 Peg: A testbed for upper main sequence stellar evolution A. Irrgang, P. De Cat, A. Pigulski, G. Handler, A. Tkachenko, and the BRITE team 275 Determination of precise stellar parameters of Kepler LEGACY targets using the WhoSGlAd method M. Farnir, M.-A. Dupret, S.J.A.J. Salmon, A. Noels, and G. Buldgen 281 From light-curves to frequencies of oscillation modes using TACO N. Themeßl, J. S. Kuszlewicz, A. García Saravia Ortiz de Montellano, and S. Hekker 287 A Novel Modeling of Magneto-Rotating Stellar Evolution K. Takahashi 293 New fully evolutionary models for asteroseismology of ultra-massive white-dwarf stars A. H. Córsico, F. C. De Gerónimo, M. E. Camisassa, and L. G. Althaus 297 Magneto-Rossby waves and short-term periodicity in solar-type stars T. Z. Zaqarashvili 301 A solution to the “solar abundance” problem Q.-S. Zhang, Y. Li, and J. Christensen-Dalsgaard 303 The Age of Zero Age Main Sequence Stars as an Analytic Function of Mass T. Steindl, and K. Zwintz 307 Contents v Study of convection in one and multi-dimensional pulsating models G. B. Kovács, R. Szabó, and J. Nuspl 309 Convection in rotating stars: convective penetration and mixing K. C. Augustson, and S. Mathis 311 Gravity offset and coupling factor of mixed modes in RGB stars C. Pinçon 313 Better Physics for Modelling Stars and their Oscillations R. Trampedach, G. Houdek, and W. Däppen 317 Binaries and clusters 319 R-mode oscillations in eclipsing binaries H. Saio 321 Stellar inclination angles from Be Star Hα emission-line profiles T.
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  • The Long-Period Galactic Cepheid RS Puppis - I

    The Long-Period Galactic Cepheid RS Puppis - I

    The long-period Galactic Cepheid RS Puppis - I. A geometric distance from its light echoes Pierre Kervella, Antoine Mérand, Laszlo Szabados, Pascal Fouqué, David Bersier, Emanuela Pompei, Guy Perrin To cite this version: Pierre Kervella, Antoine Mérand, Laszlo Szabados, Pascal Fouqué, David Bersier, et al.. The long- period Galactic Cepheid RS Puppis - I. A geometric distance from its light echoes. Astronomy and Astrophysics - A&A, EDP Sciences, 2007, 480 ( 1), pp.167 - 178. 10.1051/0004-6361:20078961. hal-00250342 HAL Id: hal-00250342 https://hal.archives-ouvertes.fr/hal-00250342 Submitted on 11 Feb 2008 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. Astronomy & Astrophysics manuscript no. ms8961.hyper15682 c ESO 2008 February 11, 2008 The long-period Galactic Cepheid RS Puppis I. A geometric distance from its light echoes⋆ P. Kervella1, A. M´erand2, L. Szabados3, P. Fouqu´e4, D. Bersier5, E. Pompei6, and G. Perrin1 1 LESIA, Observatoire de Paris, CNRS UMR 8109, UPMC, Universit´eParis Diderot, 5 Place Jules Janssen, F-92195 Meudon, France 2 Center for High Angular Resolution Astronomy, Georgia State University, PO Box 3965, Atlanta, Georgia 30302-3965, USA 3 Konkoly Observatory, H-1525 Budapest XII, P.
  • The Messenger

    The Messenger

    ESO 50th anniversary celebrations The Messenger Allocation of observing programmes La Silla–QUEST Survey b Pictoris and RS Puppis No. 150 – December 2012 – 150 No. ESO 50th Anniversary A Milestone for The Messenger in ESO’s 50th Anniversary Year Tim de Zeeuw1 nent launch of the construction of the trated book by Govert Schilling and Lars 39.3-metre diameter European Extremely Christensen (Europe to the Stars), many Large Telescope on Cerro Armazones additional images on the ESO website, 1 ESO with a projected start of operations in exhibitions and competitions, one of the about ten years’ time. Meanwhile, the latter with, as a prize, the opportunity number of Member States has increased to observe at Paranal, and a gala event In May 1974, Adriaan Blaauw launched to 14, with Brazil poised to join as the for representatives of the Member States The Messenger. He stated the goal first from outside Europe as soon as the and key contributors to ESO’s develop- explicitly: “To promote the participation Accession Agreement is ratified. ment, past and present (see the report of ESO staff in what goes on in the on p. 7, with copies of the speeches). In Organisation, especially at places of duty ESO’s mission is to design, construct and this special issue, four former Directors other than our own. Moreover, The operate powerful ground-based observ- General also contribute their reflections Messenger may serve to give the world ing facilities which enable astronomers on the significance of the 50th anniver- outside some impression of what hap­ to make important scientific discoveries sary: Lodewijk Woltjer (1975–1987), pens inside ESO.” Today The Messenger and to play a leading role in promoting Harry van der Laan (1988–1992), Riccardo is known the world over, and has reached and organising cooperation in astronomi- Giacconi (1993–1999) and Catherine a major milestone with the publication cal research.
  • Radial Velocity Observations of Classical Pulsating Stars

    Radial Velocity Observations of Classical Pulsating Stars

    Radial Velocity Observations of Classical Pulsating Stars Richard I. Anderson1 1. European Southern Observatory Karl-Schwarzschild-Str. 2, D-85748 Garching b. Munchen,¨ Germany I concisely review the history, applications, and recent developments pertaining to radial velocity (RV) observations of classical pulsating stars. The focus lies on type-I (classical) Cepheids, although the historical overview and most tech- nical aspects are also relevant for RR Lyrae stars and type-II Cepheids. The presence and impact of velocity gradients and different experimental setups on measured RV variability curves are discussed in some detail. Among the recent developments, modulated spectral line variability results in modulated RV curves that represent an issue for Baade-Wesselink-type distances and the detectability of spectroscopic companions, as well as challenges for stellar models. Spectral line asymmetry (e.g. via the bisector inverse span; BIS) provides a useful tool for identifying modulated spectral variability due to perturbations of velocity gradients. The imminent increase in number of pulsating stars observed with time series RVs by Gaia and ever increasing RV zero-point stability hold great promise for high-precision velocimetry to continue to provide new insights into stellar pulsations and their interactions with atmospheres. 1 Introduction Classical pulsating stars such as RR Lyrae stars and type-I & II Cepheids feature radial pulsations that manifest as periodic spectral variability. Radial velocity (RV) observations reduce the complexity of spectral variability (in Teff , log g, turbulence, velocity gradients, line asymmetries, among others) to a series of easy-to-interpret 1 Doppler shifts in units of km s− . Although RVs are convenient quantities to work with, their seeming simplicity can be misleading.