Active Close Binaries

897 Pages·1990·64.78 MB·English

by  Zdeněk Kopal (auth.), Cafer İbanoğlu (eds.)

Active Close Binaries
NATO ASI Series
Advanced Science Institutes Series
A Series presenting the results of activities sponsored by the NATO Science Committee,
which aims at the dissemination of advanced scientific and technological knowledge,
with a view to strengthening links between scientific communities.
The Series is published by an international board of publishers in conjunction with the
NATO Scientific Affairs Division
A Life Sciences Plenum Publishing Corporation
B Physics London and New York
C Mathematical Kluwer Academic Publishers
and Physical Sciences Dordrecht, Boston and London
D Behavioural and Social Sciences
E Applied Sciences
F Computer and Systems Sciences Springer-Verlag
G Ecological Sciences Berlin, Heidelberg, New York, London,
H Cell Biology Paris and Tokyo
Series C: Mathematical and Physical Sciences· Vol. 319
Active Close Binaries
edited by
Cafer ibanoglu
Ege University Science Faculty,
Astronomy and Space Sciences Department,
Bornova, Izmir, Turkey
Kluwer Academic Publishers
Dordrecht / Boston / London
Published in cooperation with NATO Scientific Affairs Division
Proceedings of the NATO Advanced Study Institute on
Active Close Binaries
Ku~adasl, Turkey
September 11-22, 1989
Ubrary of Congress Cataloglng-In-Publlcatlon Data
NATO Advanced Study InstItute on ActIve Close BInarIes (1989
Ku~adasl. Turkey)
ActIve close bInarIes I edIted by Cafer tbanoglu.
p. CI. -- (NATO AS1 serIes. SerIes C. Mnheutlcal and
physIcal scIences; yol. 319)
'ProceedIngs of the NATO Advanced Study InstItute on ActIve Close
BInaries. Ku~adaSl. Turkey. Septeaber 11-22. 1989.'
'PUbll$hed In cooperillon wtth NATO SCIentifIc Affatrs DIVISIon.'
Includes tndex.
1. Stars, Doutl1,--Congress8$. 2. Stirs, lIarUbl,--Congruus.
I. IDanoglu. Caftr, 19'16- II. North "tllntlc Truty
OrganizatIon. ScIentifIc AffaIrs DivISion. III. Tlth.
IV. SerIes, NATO "51 s.rIIS. Sir liS C. Math,.atlc. l .nd physlc.l
SCIences: no. 319.
OB821.N375 1989
523.8' <l1--dc20 90-44193
ISBN·13: 978·94·010·6790·4 e·ISBN·13: 978·94·009·0679·2
001: 10.I007f978·94·009·0679·2Z
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TABLE OF CONTENTS
PREFACE: C. ibanoglu IX
SCIENTIFIC AND ORGANIZING COMMITTEE Xl
CONFERENCE PHOTOGRAPH XlI
LIST OF PARTICIPANTS
XV
OPENING REMARKS: Physical Causes of the Light 1
Variations of Active Binary Systems and their
Interpretation: Z. Kopal
1. INTERACTION IN BINARIES AND ALGOLS
E. F. Guinan and Eclipsing Binaries as Astrophysical 7
S. M. Carroll Laboratories and the Strange Case of
Epsilon Au rigae
M. J. Plavec Accretion Disks in Non-Degenerate Binaries 37
M. J. Plavec Resolving the Puzzle of the W Serpentis Stars 49
R. H. Koch Extragalactic Interacting Binaries 61
M. Kitamura Effective Gravity-Darkening of Close Binary 69
Systems
R. H. Koch and Binary Activity at the Top of the Main 81
R. J. Pfeiffer Sequence: Y Cyg and U Oph
D. S. Hall Period Changes and Magnetic Cycles 95
A. Gimenez and Absolute Dimensions of Classical Algol-Type 121
J. M. Garcia Binaries
A. Gimenez Recent Results of Apsidal Motion Studies 137
in Eclipsing Binaries
T. Mazeh, On the Orbital Circularization of Close 145
D. W. Latham, Binaries
R. D. Mathieu
and B. W. Carney
H. Mauder Stellar Structure and Evolution with 155
respect to Binarity
vi
F. Barone, L. Milano An Optimization Method for Solutions of 161
and G. Russo Close Eclipsing Binaries
P. B. Etzel Spectrophotometry of Algol-Type Binaries 189
P. B. Etzel Complications in the Balmer-Line Spectrum 203
of TT Hydrae
P. G. Niarchos and An Optimization Technique for the 213
G. Pantazis Fourier Analysis of the Light Curves
of Totally Eclipsing Systems of
Algol Type
J. R. W. Heintze The Algol-Type Binary U Coronae Borealis: 219
a Triple?
P. Koubsky, J. Horn, Interacting Binary CX Draconis 237
P. Harmanec,
G. J. Peters and
R. S. Polidan
J. F. Lu Disk-Driven Precession in Active Close Binaries 239
and in Active Galactic Nuclei
J. S. Shaw Near-Contact Binary Stars 241
H. Rovithis-Livaniou, Observations and Light Curve Analysis of 253
P. G. Niarchos Eclipsing Binaries of W UMa Type
and P. Rovithis
T. Mazeh, D. W. La- A Radial Velocity Search for Brown Dwarfs 267
tham, R. P. Sfef- and the Low-Mass Companion
anik, G. Torres
and E. Wasserman
Z. Miiyesseroglu, O. Photometry of Some Close Binaries at 277
Demircan, E. Der the Ankara University Observatory
man and S. Selam
D. S. Hall and Circularization, Synchronization, and Differ- 287
G. W. Henry ential Rotation in Chromospherically Active Binaries
2. BINARY EVOLUTION AND THE CONTACT QUESTION
C. Maceroni and Do Thermally Decoupled Late-Type Contact 309
F. Van't Veer Binaries Really Exist?
F. Van't Veer and The Evolution of the Period and Synchronization 321
C. Maceroni for Close G-type MS Binaries
J. R. W. Heintze, The A-Type W UMa System AW UMa 331
J. J. M. In't Zand
and F. Van't Veer
vii
S. Catalano Rotation and Activity 347
B. H. Foing Solar-Like Magnetic Structures in 363
Active Close Binaries
D. S. Hall and Starspot Lifetimes 377
M. R. Busby
R. F. Webbink and Tidal Torques and Magnetic Stellar 393
M. S. Hjellming Winds in RS CV n Binaries
S. Catalano Flares on RS CVn and Related Binaries 411
O. Demircan Activity and Evolution in RS CVn Systems 431
D. H. Bradstreet and Deciphering Long-Term Photospheric and 467
E. F. Guinan Chromospheric Activity on the Contact Binary
Binary VW Cephei
K. G. Strassmeier Synoptic Doppler Imaging and Photometry of 485
Spotted Chromospherically Active Stars
F. Scaltriti Infrared Studies on Active Binaries and 493
Circumstellar Matter
M. J. Arevalo and Infrared Photometry of RS CVn Short 501
C. Lazaro Period Systems
K. G. Strassmeier On Chromospheric Emission and Photometric 509
Variability of Active Late-Type Stars
3. HIGH ENERGY BINARIES AND EXOTIC OBJECTS
C. ibanoglu Long-Term Observations of Active Binaries 515
K. Olah Similarities and Differences between the Light 545
Variability of the K Giant and Dwarf Active
Binaries HK Lac and BY Dra
J. E. Armentia, M. J. Recent Measures of Call Hand K Chromospheric 551
Fernandez-Figueroa, Fluxes in a Sample of RS CVn Systems
M. Cornide
E. de Castro
and J. Fabregat
S. Evren Photometric Variability of II Peg 561
C. Lazaro Activity Cycle in the RS CVn System II Peg 573
A. Esendemir and Low Flux Line Profiles on the IUE Spectra 579
U. Kiziloglu of II Peg
M. C. Akan A Photometric Study of UV Psc 591
M.Orio Novae and their Non-Spherically-Symmetric 601
Explosions
J. A. Mattei Optical Properties of Cataclysmic Variable 611
viii
Stars
C. A. la Dous IUE Spectra of Cataclysmic Variables: 629
Observational Results and Theoretical Implications
L. Milano, F. Barone Binaries and Pulsars as Gravitational Wave Sources: 639
and G. Russo Possibility of Direct Detection by Ground Based
Experiments
T. J. Herczeg Neutron Star Masses 693
D. J. Barry High Angular Resolution Studies of Binaries 729
at Georgia State University
S. Bowyer Extreme Ultraviolet Spectroscopy as a Probe 737
of Active Close Binaries
4. COOL CLOSE BINARIES AND RS CVn STARS
J. L. Linsky Modelling the Coronae and Chromospheres of RS CV n 747
Systems by the Analysis of Ultraviolet, X-Ray and
Radio Observations
J. Kuijpers Magnetic Flares in Close Binaries 761
J. E. Neff The Evolution of Chromospheric Structure 805
on AR Lacertae
J. E. Neff Spatial Resolution of Stellar Atmospheres within Active 809
Close Binaries
T. Banks and Information Limit Optimization Techniques Applied to 821
E. Budding AB Dor
E. Budding and The Complementarity of Doppler Imaging and Starspot 831
M. Zeilik Modelling
B. H. Foing Perspectives for Ground-Based and Space 845
Research on Active Close Binaries
B. Zafiropoulos and Unified Treatment of Satellite Motion in Various 859
F. Zafiropoulos Potential Fields
V. Keskin Light Curve Variations of the RS CVn Type 865
Eclipsing Binary ER Vulpeculae
P. B. Etzel and Synthesis Methods for Eclipsing Binary 873
K. C. Leung Light Curves
K. C. Leung Types of Contact Binary Systems and Ways 881
to Find Them
M. T. Edalati and A Photometric Analysis of Eclipsing Systems 891
K. C. Leung in NGC188
INDEX 897
PREFACE
Since the 1970s symposia or colloquia devoted to recent research on close
binaries have been held around the world almost annually. At meetings of the
General Assembly of the International Astronomical Union this topic has also
been discussed in detail at presentations in various commission meetings and
also as invited talks by leading astronomers in the field. In recent years,
fundamental changes have taken place in the study of close binaries due to the
improvements in observational techniques, extension of observations from X-ray
to radio regions of the electromagnetic spectrum, and advances in theoretical
studies.
For more than a decade, a group of astronomers at Ege University Observatory
has been concentrating on active close binaries with particular emphasis on
the behaviour of the light curves of chromospherically active systems. Thus,
we decided to organize an international meeting in Western Anatolia, where
this part of Turkey had been the cradle for great developments in science
during antiquity. KUljadasi, located only minutes away from Ephesus, one of
the seven wonders of the world, was selected to be the meeting site.
Close binary systems constitute a very rich source of information about the
physical properties of the component stars. Some systems are eclipsing
variables, where periodic recurrences of eclipses are observed as
comparatively brief decreases in the total brightness of the binary system.
Precise methods of photometric observations make it possible to obtain the
light variations of these systems because of eclipses and other phenomena.
Therefore, close binaries may be considered as astrophysical laboratories.
The subject matter encompasses a number of broad areas, related to different
classes of binaries. The specific areas that were discussed at this meeting
were broad, extending from systems such as Algols and W Serpentis stars which
are non-degenerate binaries with circum stellar disk and wind structures; to
near-contact short period binaries with starspots; chromospheric and coronal
activity indicators; and cataclysmic variables and X-ray emitting neutron
stars with close binary components which are· in the advanced stages of
evolution of close binary phenomena.
The light variations of close binaries, excluding the changes from eclipses,
were addressed by two different models: il Photometric effects by oscillating
components, and ii) Star-spot and other surface inhomogeneities on close
binary companions. The data, gathered with different techniques, indicated
that such binaries are commonly chromospheric-active and have large, hot
coronae and play an important role in understanding the evolution of the
stellar components and the structure of their atmospheres and coronae.
Studies of the outer atmospheres may in fact lead to better understanding of
solar activity. Although the meeting concentrated on the phenomena associated
with the outer atmospheres of the late-type components of these systems, other
related topics of interest such as mass-exchange, mass-transfer, and mass loss
were also discussed.
ix
x
Recent advances, such as space-borne instruments and new generation
ground-based equipment are having profound effects in the study of active
close binaries. The data obtained from X-ray to radio wavelengths allow us to
model the coronae and chromospheres of chromospherically active RS CVn
systems. The relations between activity and evolution in the RS CVn systems
were discussed in detail. Theoretical implications of magnetic flares, tidal
torques, and magnetic stellar winds in active binaries were compared with
observational results. Period changes, particularly in chromospherically
active binaries and synthronization of starspot lifetimes with activity cycles
were also considered.
Many phenomena observed in active close binaries could not be explained by
the starspot hypothesis alone. Observations of active binaries planned for
the next decade from both ground- and space-based observatories, will
hopefully lead to further advances in the field.
The meeting was supported financially by NATO and partly by the Scientific
and Research Councils of Greece and Turkey. I want to express my very sincere
thanks to these organizations, whose financial support made this meeting
possible to organize. The Scientific Committee made every effort to assure
the success of the meeting. All the local arrangements, including very
successful social programmes were on the shoulders of the Local Organizing
Committee. Their dedicated work and help throughout the meeting will be
remembered by all. Special thanks to Professor Zdenek Kopal and Dr. Janet
AkyUz Mattei, who did not spare their help at ~very aspect of the meeting.
Last, but not least, I would like to thank all the speakers for their
scientific contributions and for sending me their camera-ready manuscripts
which helped to make my editorial responsibilities much easier. Finally, my
sincere thanks to Kluwer Academic Publishers, especially Mrs. Nel de Boer, for
their excellent cooperation.
22 January 1990