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. A. A. Sigut, A. K. Mahjour, and C. Tycner 325
Binary stars: a cheat sheet J. Southworth 329
Hot Subdwarf Stars and Binary Evolution D. Brown 335
Eclipsing binaries with possible β Cephei variables F. Kahraman Aliçavuş, and G. Handler 339
Results of the ensemble asteroseismology of B-type stars in open cluster NGC 6910 D. Moździerski, A. Pigulski, Z. Kołaczkowski, G. Michalska, G. Kopacki, F. Carrier, P. Walczak, A. Narwid, M. Stęślicki, J.-N. Fu, et al. 341
β-Cep pulsator in the eclipsing binary V381 Car: mode identification and seismic modelling A. Miszuda, J. Daszyńska-Daszkiewicz, and W. Szewczuk 345
KIC 10661783 – binary system with a δ Sct type component A. Miszuda, W. Szewczuk, and J. Daszyńska-Daszkiewicz 349
KIC 9163796 – a benchmark binary for age determination D. H. Grossmann, P. G. Beck, and A. Hanslmeier 351
The spectroscopic multiplicity fraction in a sample of A/F-type (candidate) hybrid stars from the Kepler mission P. Lampens, L. Vermeylen, P. De Cat, Á. Sodór, Zs. Bógnar, Y. Frémat, M. Skarka, H. Lehmann, A. Samadi, L. Fox-Machado, et al. 353
Possible Connection Between P Cygni and Neighboring Open Clusters S. Beradze, and N. Kochiashvili 355
Parameters of detached O- and B-type eclipsing binaries in the LMC M. Taormina 357
Other and more challenges 361
Protostellar accretion bursts and their effect on pre-main-sequence stellar evolution E. Vorobyov, and V. Elbakyan 363 vi Stars and their variability, observed from space
Recent advances in numerical models that include atomic diffusion in stars G. Alecian 367
The photometric variability of magnetic hot stars: deviations from centered dipoles M. S. Munoz, and G. A. Wade 371
From Ancestors to Offspring: tracing the connection between magnetic fluxes of OB and neutron stars E. I. Makarenko, A. P. Igoshev, and A.F. Kholtygin 375
Rotational inversions along the lower part of the red-giant branch F. Ahlborn, E. P. Bellinger, S. Hekker, S. Basu, and G. C. Angelou 377
Analysis of Photometry of Stars from Space and Ground-Based Surveys D. E. Tvardovskyi, I. L. Andronov, K. D. Andrych, and L. L. Chinarova 381
From monitoring survey of variable red giant stars to the evolution of the galaxy: Andromeda VII M. Navabi, M. Noori, E. Saremi, A. Javadi, J. van Loon, and H. Khosroshahi 383
Stellar spheres of influence 387
Disks around Be stars and complex radiation effects N. D. Kee 389
Tracing stellar wind variability from space J. Krtička, and A. Feldmeier 395
Star–planet magnetic interactions A. F. Lanza 403
Dynamics of star-disk interaction processes in young, low-mass stars as seen from space L. Venuti 409
Cepheid Spheres of Influence N. R. Evans, H. M. Günther, H. E. Bond, G. H. Schaefer, B. D. Mason, M. Karovska , E. Tingle , S. Wolk et al. 415
The distance of the long-period Cepheid RS Puppis from its remarkable light echoes P. Kervella 419
BRITE Photometric Variability of the Intriguing Wolf-Rayet Star WR6: Rotational or Binary Modulations? N. St-Louis, A.F.J Moffat, T. Ramiaramanantsoa, and G. Lenoir-Craig 423
Do planet systems influence the host star atmospheric abundances ? T. Ryabchikova 427
Flares of M stars in the Upper Scorpius region and flares/CMEs of the active M-star ADLeo E. W. Guenther, D. Wöckel, and P. Muheki 431
Starspots and rotation velocities of normal A- and Am- stars O. Trust, E. Jurua, P. De Cat, and S. Joshi 433
Ultraviolet variability of B, Be, and B[e] stars I. Krtičková, and J. Krtička 435
Type II Cepheids in the Kepler K2 mission M. I. Jurkovic, E. Plachy, L. Molnár, M. A. T. Groenewegen, and R. Szabó 437
Transiting exocomets detected in broadband light by TESS in the β Pictoris system S. Zieba, K. Zwintz, M. A. Kenworthy, and G. M. Kennedy 439 Contents vii
The influence of stellar X-ray and UV radiation on exoplanets S.R.G. Joyce, J.P. Pye, J.D. Nichols, and The Exoplanets-A consortium 441
The Ondřejov Exoplanet Group M. Blažek, P. Kabáth, M. Skarka, T. Klocová, M. Špoková, J. Šubjak, J. Dvořáková, J. Žák, D. Dupkala, and E. Plávalová 443
Southern Bp-e star HD124448 M. Zboril 447
Lessons learned 449
BRITE-Constellation Operations and Data Collection R. Kuschnig 451
Solar-Like Oscillations: Lessons Learned & First Results from TESS D. Huber, K. Zwintz, and the BRITE team 457
RR Lyrae and Cepheid variables with TESS E. Plachy, and TASC WG6 465
Magnetic OB[A] Stars with TESS: probing their Evolutionary and Rotational properties - The MOBSTER Collaboration A. David-Uraz, C. Neiner, J. Sikora, J. Barron, D. M. Bowman, P. Cerrahoğlu, D. H. Cohen, C. Erba, V. Khalack, O. Kobzar, et al. 471
TOSC: an algorithm for the tomography of spotted transit chords G. Scandariato 475
Asteroseismic analysis of the SPB star HD 54967 observed by TESS P. Walczak, W. Szewczuk, and J. Daszyńska-Daszkiewicz 479
Eclipsing binaries hiding in the background: the Kepler pixel project A. Forró, and R. Szabó 481
Conclusion 483
Celebrating five years of BRITE-Constellation with good good good, good vibrations during the end-of- conference summary party C. Aerts 485
Author Index 487