Activity in Red-Dwarf Stars: Proceedings of the 71st Colloquium of the International Astronomical Union Held in Catania, Italy, August 10–13, 1982

Front Matter....Pages i-xxvi
Introductory Address....Pages 1-3
Magnetic Fields and Activity of the Sun and Stars: An Overview....Pages 5-14
Front Matter....Pages 15-15
Global and Photospheric Physical Parameters of Active Dwarf Stars....Pages 17-33
Mean Colors and Effective Temperatures of K and M Dwarfs....Pages 35-38
The Quiescent Chromospheres and Transition Regions of Active Dwarf Stars: What are We Learning from Recent Observations and Models?....Pages 39-60
The Structure and Energy Balance in Main Sequence Stars....Pages 61-65
The Distribution of Chromospheric Emission Strengths Among Red Dwarfs....Pages 67-70
Chromospheric Emission and Rotation of Main Sequence Stars....Pages 71-73
Late-Type Ca II Emission-Line Stars in the Southern Hemisphere....Pages 75-76
The Atmosphere of a Probably Very Young by Dra-Type Flare Star....Pages 77-77
Some Properties of Stellar Transition Regions....Pages 79-81
Quiescent Coronae of Active Chromosphere Stars....Pages 83-108
Einstein and IUE Observations of Nearby Red Dwarfs....Pages 109-124
X-Ray Emission from Flare Stars....Pages 125-129
Stellar X-Ray Activity in the Hyades....Pages 131-134
Front Matter....Pages 135-135
Spots, Spot-Cycles and Magnetic Fields of Late-Type Dwarfs....Pages 137-156
Optical Photometry of Flares and Flare Statistics....Pages 157-174
The ITA Survey on Red Dwarf Variable Stars — Final Report....Pages 175-177
Synopsis of by Dra and II Peg Light Curves: Variability and Possible Evidence of Differential Rotation....Pages 179-184
Two-Spot Modeling of Synoptic Light Curves of II Peg....Pages 185-188
Front Matter....Pages 135-135
Variable K-Type Stars in the Pleiades....Pages 189-193
Stellar Activity and Calcium Emission Variability....Pages 195-199
EV Lacertae: Is Flare Activity Related to an Unseen Planet-Like Companion?....Pages 201-202
An Unusual Flare on EV Lac....Pages 203-205
Optical and Ultraviolet Stellar Flare Spectroscopy....Pages 207-221
Results from Optical and UV Stellar Flare Spectroscopy....Pages 223-235
Observations of H β and He II λ 4686 Lines in the Spectra of Flares of UV Cet-Type Stars....Pages 237-238
The Timescales of Variations in Continuum and Hydrogen Lines During Stellar Flares....Pages 239-243
Far-Ultraviolet and Visible Observations of Flares on dMe Stars....Pages 245-248
IUE Spectra of the by Dra/Flare Star AU Mic....Pages 249-250
Flare-Like Activity of Red Giant Stars....Pages 251-254
X-Ray Observations of Stellar Flares....Pages 255-272
Quiescent and Flaring Radio Emission From dMe Stars....Pages 273-286
Flares on the Sun : Selected Results from SMM....Pages 289-305
Flares on the Sun : Selected Results from Hinotori....Pages 307-320
Solar Flares with SMM and Implications for the Physics of Stellar Flares....Pages 321-324
The Interpretation of EUV Spectra of Sunspots....Pages 325-326
Possible Origins for the 12μ Emission Lines in the Solar Spectrum....Pages 327-330
Multiple Wavelength Observations of Flaring Active Regions....Pages 331-334
Magnetic Development of Flaring Regions at Centimeter Wavelengths....Pages 335-337
Very Long Baseline Interferometry of Solar Flares....Pages 339-341
RS CVn Stars: Photospheric Phenomena and Rotation....Pages 343-361
RS CVn Stars: Chromospheric Phenomena....Pages 363-377
Doppler Imaging of Starspots....Pages 379-385
Twenty Years of Dedicated Photometry of Rs CVn at Catania Observatory....Pages 387-390
Periods of Unevolved Late-Type Close Binaries: Evidence of Magnetic Activity....Pages 391-392
Migrating Waves in Solar-Type Short-Period Eclipsing Binaries....Pages 393-394
Features of the Wave-Like Distortion in Some RS CVn Binaries....Pages 395-398
On the Distortion Wave in the Short Period RS CVn Type Eclipsing Binary WY Cancri....Pages 399-400
Recent Photometry of AR Lacertae....Pages 401-402
HK Lacertae....Pages 403-405
The Solar-Type Eclipsing Binary System AI Phoenicis....Pages 407-408
Light Curves and Ca II Emissions of V711 Tauri during 1981–82....Pages 409-410
A Flare-Like Event from the Short-Period System XY UMa....Pages 411-413
RS CVn Systems : The High Energy Picture....Pages 415-427
Preliminary Results of a Five-Year Survey of Radio Emission from RS CVn and Similar Binaries....Pages 429-437
Activity Correlations in Close Binary Systems....Pages 439-442
IUE Spectra of RS CVn Stars....Pages 443-444
Coronal and Chromospheric Structure in AR Lac. II. Physical Characteristics of the Atmosphere....Pages 445-446
Contact Binary Stars....Pages 447-461
The Evolutionary Status of Short-Period Rs CVn and Related W UMa Eclipsing Binaries....Pages 463-464
Angular Momentum Loss and the Formation of W UMa Systems....Pages 465-468
Activity of Contact Binaries....Pages 469-473
Rotation-Activity Connections in Main Sequence Binaries....Pages 475-477
The VW Cephei System....Pages 479-480
A Bright Spot and a Serendipitous Stellar Flare on the Contact-Binary VW Cep....Pages 481-483
Numerical Analysis of Orbital Period Variations and a Mechanism for Changes in the Light Curve of VW Cep....Pages 485-486
On Activities of UV Cet-Type Flare Stars and of T Tau-Type Stars....Pages 487-495
The Variability of The T Tauri Star DI Cephei....Pages 497-500
Optical Monitoring of T Tauri Stars....Pages 501-502
Periodic Light Variability in Four Late-Type Pre-Main-Sequence Stars....Pages 503-504
New Results on the Binary Companion of T Tauri....Pages 505-507
Chromospheric Properties of T Tauri Stars Determined from EUV Spectra....Pages 509-511
Quasi-Periodic Variations of Balmer Line Profiles in Spectra of the T Tau-Type Star RW Aurigae....Pages 513-514
Eruptive Phenomena as a Source of the Observed Variations of Intrinsic Polarization in Long-Period and T Tauri Variables....Pages 515-518
The Interaction of Fast Particles with Frozen Gases in T Tau Nebulae: The Physical Background....Pages 519-521
On The Origin of H 2 in T Tau Stars....Pages 523-524
Front Matter....Pages 525-525
Models of Spots and Flares....Pages 527-543
Magnetic Instabilities in Stellar Atmospheres....Pages 545-558
Flaring Processes in Stellar Atmospheres: The Importance of Electromagnetic Coupling....Pages 559-560
Front Matter....Pages 525-525
Empirical Models of Stellar Flares : Constraints on Flare Theories....Pages 561-578
Dynamo Theory in the Sun and Stars....Pages 579-599
Photospheric Sources of Magnetic Field Aligned Currents....Pages 601-603
Turbulent Sound Generation in Red Dwarf Stars....Pages 605-608
A New Triggering Mechanism for Red Dwarf Flares....Pages 609-611
Theory and Observations of Negative Preflares in UV Cet Stars....Pages 613-615
Flares on Red Dwarf Stars as a Result of the Dynamical Response of the Chromosphere to the Heating....Pages 617-619
MHD Thermal Instabilities in Cool Inhomogeneous Atmospheres....Pages 621-623
Magnetic Accretion Model for the Activities of Very Young Stars....Pages 625-627
Interacting Magnetospheres in RS CVn Binaries — Coronal Heating and Flares....Pages 629-632
Basic Parameters Determining X-Ray Emission Level in Stars of Spectral Type Later Than F5....Pages 633-635
Front Matter....Pages 637-637
Future Research Directions: Theoretical Approach and Perspective....Pages 639-650
Observational Approach and Perspective....Pages 651-652
Summary of the Colloquium....Pages 653-661
Back Matter....Pages 663-669