Magnetodynamic phenomena in the solar atmosphere : prototypes of stellar magnetic activity : proceedings of the 153rd Colloquium of the International Astronomical Union, held in Makuhari, near Tokyo, May 22-27, 1995

These are the Proceedings of Colloquium No. 153 of the International Astro­ nomical Union, held at Makuhari near Tokyo on May 22 - 26, 1995, and hosted by the National Astronomical Observatory. This meeting was intended to be an interdisciplinary meeting between re­ searchers of solar and stellar activity, in order for them to exchange the newest information in each field. While each of these areas has seen remarkable advances in recent years, and while the researchers in each field have felt that information from the other's domain would be extremely useful in their own work, there have not been very many opportunities for intensive exchanges of information between these closely related fields. We therefore expected much from this meeting in pro­ viding stellar researchers with new results of research on the counterparts of their targets of research, spatially and temporarily resolved, as observed on the Sun. Likewise we hoped to provide solar researchers with new results on gigantic ver­ sions of their targets of research under the very different physical circumstances on other active stars. It was our greatest pleasure that we had wide attendance of experts and active researchers of both research fields from all over the world. This led to extremely interesting talks and very lively discussions, thereby stimulating the exchange of ideas across the fields. Front Matter....Pages i-xix Front Matter....Pages 1-1 Coronal Structures, Local and Global....Pages 3-11 Dynamical Processes in the Solar Corona....Pages 13-20 Heating Mechanisms of the Solar Corona....Pages 21-27 Solar Coronal Heating: MHD Models and Observational Signatures....Pages 29-36 Heating of Active Region Corona by Transient Brightenings (Microflares)....Pages 37-38 The Heating of Soft X-Ray Coronal Loops....Pages 39-40 Temperature Structure of Solar Active Regions....Pages 41-42 Temperature and Heating Distributions along the Steady Coronal Loops....Pages 43-44 Long Time Statistics of Magnetically Driven MHD Turbulence, Solar Flares and Coronal Heating....Pages 45-46 Mass-Flow Effects on Wave Heating by Resonant Absorption....Pages 47-48 Hα Surges and X-Ray Jets in AR7260....Pages 49-50 Surface Driven Evolution and Activity of Atmospheric Magnetic Structures....Pages 51-52 Chromospheres of Coronal Stars....Pages 55-62 Evidence of Magnetic Coronae in Other Stars....Pages 63-70 Recent VLBI Observations of Stellar Coronae....Pages 71-80 Coronal Structure in M Dwarf Stars....Pages 81-82 X-Ray and EUV Observations of Active Binary Stellar Coronae: Relationships to Solar Studies of Flare Parameters and Coronal Abundances....Pages 83-84 Element Abundances in Stellar Coronae....Pages 85-86 Front Matter....Pages 87-87 Yohkoh Observations of Coronal Mass Ejections....Pages 89-96 Quiet Corona and Mass Loss....Pages 97-106 Front Matter....Pages 87-87 Mechanisms of Solar (and Stellar) Mass Loss....Pages 107-114 Acceleration of the High Speed Solar Wind....Pages 115-122 Declining Phase Coronal Evolution: The Statistics of X-ray Arcades....Pages 123-124 Development of a Coronal Helmet Streamer of 24 January 1992....Pages 125-126 Observations of Solar Wind Beyond 5 R s and within 0.3 AU by Interplanetary Scintillation....Pages 127-128 HST and IUE Observations of Stellar Mass-Loss from K and Early M Evolved Stars....Pages 131-138 Prominences on Late Type Active Stars....Pages 139-146 Stellar CMES and Flare Mass Motions....Pages 147-155 X-Ray Emission from O-Stars....Pages 157-158 Front Matter....Pages 159-159 Evidence of Magnetic Reconnection in Solar Flares....Pages 161-168 Non-Thermal processes and Superhot Plasma Creation in Solar Flares....Pages 169-176 Mass Motions in Flares....Pages 177-184 Energy Build-Up Processes of Solar Flares Studied by Optical Observations....Pages 185-194 High-Quality Images Based on the Steer Algorithm Decovolution from the Correlation Data Observed with Nobeyama Radioheliograph....Pages 195-201 Loop-Top Hard X-Ray Source in Solar Flares....Pages 203-204 Radio Imaging Observation of a Solar Flare Cusp....Pages 205-206 Flares and Plasma Flow Caused by Interacting Loops....Pages 207-208 Electron Time-of-Flight Measurements....Pages 209-210 Hot and Cool Post-Flare Loops: Formation and Dynamics....Pages 211-212 Ultraviolet (1200 To 1800 Å) Emission During the Impulsive Phase of a Class 3b-X3 Solar Flare Observed with Solstice....Pages 213-214 Front Matter....Pages 159-159 Optical Emission from Stellar Flares....Pages 217-225 Flares on Active Binary Systems....Pages 227-234 Stellar X-Ray Flares....Pages 235-242 Hard X-Ray Emissions from Protostar Candidates....Pages 243-246 X-Ray Flares and Variability of Young Stellar Objects....Pages 247-258 Radio Emission from Solar and Stellar Flares....Pages 259-266 Radio Evidence for Nonthermal Magnetic Activity on Main-Sequence Stars of Late Spectral Type....Pages 267-276 An Analysis of X-Ray Flares in Pleiades Stars....Pages 277-278 Simultaneous X-Ray, EUV, UV, and Radio Observation of the Corona of the RS CVN Binary HR1099....Pages 279-280 On the Origin of Intense Radio Emission from Solar and Stellar Flares....Pages 281-282 Magnetic Structures and Giant Flares in HR1099....Pages 283-284 Arcade Flare Models....Pages 287-294 Problems for Arcade and Loop Flare Models Revealed by Yohkoh ....Pages 295-302 Bifurcation and Stability of the Coronal Magnetic Field....Pages 303-304 MHD Simulations Of Coronal Current Sheet Dynamics....Pages 305-306 The Active Role and Models of Reconnecting Current Sheets in the Solar Atmosphere....Pages 307-308 The Evolution of Magnetic Arcades under Footpoint Motion....Pages 309-310 Hydrodynamic Modeling of Flares Well-Observed by Yohkoh/SXT....Pages 311-312 On Thermal Hydrodynamical Model of Solar Flares....Pages 313-314 MHD Simulation of X-Ray Jets Based on Magnetic Reconnection Model....Pages 315-316 Front Matter....Pages 159-159 Energy Release in the Current-Carrying Magnetic Loops....Pages 317-318 Front Matter....Pages 319-319 Magnetic Activity Cycle in the X-ray Coronal Structures....Pages 321-328 The Dynamics of Magnetic Flux Tubes in the Solar Convection Zone....Pages 329-336 Hot Spots for Solar Activity....Pages 337-344 Solar Dynamo Driven by Global Convection and Differential Rotation and the Magneto-Thermal Pulsation of the Sun....Pages 345-354 Formation of a Kinked Alignment of Solar Active Region....Pages 355-356 Stellar Magnetic Activity, Activity Cycles, and Dynamos....Pages 359-366 Recent Measurements of Stellar Magnetic Fields....Pages 367-374 Active Longitudes and Rotation of Active Stars....Pages 375-386 Dynamos in Different Types of Stars....Pages 387-394 Coronal Magnetic Activity in Low Mass Pre-Main Sequence Stars....Pages 395-396 Front Matter....Pages 397-397 The Sun as the Ultimate Challenge to Astrophysics: The Vital Phase of Solar Physics....Pages 399-410 Front Matter....Pages 411-411 Measurement of the Coronal Electron Temperature at the Total Solar Eclipse On 3rd Nov. 1994....Pages 413-414 Results From 3 November 1994 Solar Eclipse....Pages 415-416 Interpretation of SXT Data Concerning the Diffuse Corona....Pages 417-418 Temperature Structure of the Diffuse Corona....Pages 419-420 Measurements of Active and Quiet Sun Coronal Plasma Properties with Serts EUV Spectra....Pages 421-422 Calculations of Soft X-ray Images from MHD Simulations of Heating of Coronal Loops....Pages 423-424 2D and 3D Nonlinear MHD Simulations of Coronal Loop Heating by Alfvén Waves....Pages 425-426 Generation of Linear and Nonlinear Magnetic Tube Waves in the Solar Atmosphere....Pages 427-428 Front Matter....Pages 411-411 Magnetic Roots of Enhanced High Coronal Loops....Pages 429-430 Dynamic Behavior of the Coronal Streamer Belt....Pages 431-432 Minor Photospheric and Chromospheric Magnetic Activity and Related Coronal Signatures....Pages 433-434 HEI10830Å in Solar Active Regions and its Correlat with Chromospheric Lines....Pages 435-436 X-ray and Magnetic Features of H α Surges....Pages 437-438 High Resolution Observation of Solar Spicules and their Kinematic Modelling....Pages 439-440 Location of Type I Radio Continuum and Bursts on Yohkoh Soft X-ray Maps....Pages 441-442 Coronal Magnetic Fields from Polarization Observations at Microwaves....Pages 443-444 Detection of Nonthermal Radio Emission from Coronal X-ray Jets....Pages 445-447 Statistical Study of Solar X-Ray Jets Observed with the Yohkoh Soft X-Ray Telescope....Pages 449-450 Simultaneous Observation of Solar Surges in Hα and X-Ray....Pages 451-452 Statistical Studies of Solar Hα Brightening Events and Their Relation to Soft X-Ray Events....Pages 453-454 The Three-Dimensional Structures of Elementary Coronal Heating Events....Pages 455-456 Causal Relation Between Hα Arch Filament Loops and Soft X-Ray Coronal Loops....Pages 457-458 Emerging Flux, Reconnection, and XBP....Pages 459-460 Collision of Plasma Flows in a Current Loop....Pages 461-462 Oscillations in a Quiescent Solar Prominence....Pages 463-464 Non-Equilibrium Effects on the Optically Thin Radiative Loss Function....Pages 465-466 Nonlinear Dissipation of Alfvén Waves....Pages 467-468 On the Stability of Solar Photospheric Magnetic Flux Tubes....Pages 469-470 Front Matter....Pages 411-411 A General Code for Modeling MHD Flows on Parallel Computers: Versatile Advection Code....Pages 471-472 A Regridding Algorithm for High Resolution Hydrodynamics of Flaring Coronal Loops....Pages 473-474 Rotational Modulation of Hα Emission in RS CVN Systems....Pages 475-476 Radio and X-Ray Emission in Stellar Magnetic Loops....Pages 477-478 Coronal Properties of Nearby Old Disk and Halo DM Stars....Pages 479-480 Spectral and Spatial Structure of η Carinae....Pages 481-482 Comparison of High Resolution Optical and Soft X-Ray Images of Solar Corona....Pages 483-485 Large-Scale Arcade Formation on May 15, 1992 and its Interplanetary Consequence....Pages 489-490 Observations of a Quiescent Prominence Straddling the Solar Limb during the Total Eclipse of 11 July 1991....Pages 491-492 Yohkoh SXT Observations of Prominence Eruption and Disappearance....Pages 493-494 Polar X-Ray Arcade Formation and Giant Cusp....Pages 495-496 The Skew of X-Ray Coronal Loops Overlying Hα Filaments....Pages 497-498 Studies of Solar Wind Onset in Coronal Holes Planned for Soho....Pages 499-500 Low-Speed Solar Winds from Active Regions....Pages 501-502 Detection of Active Region Expansion in Interplanetary Space by Sakigake Spacecraft at 1 AU....Pages 503-504 Kelvin-Helmholtz Instability in Coronal Rays....Pages 505-506 Formation Of Contact Binaries Via A Magnetized Wind, A Parameter-Free Model....Pages 507-508 Formation of Reconnection-Driven Jets With Disk Accretion Onto Magnetized Young Stars....Pages 509-510 Magnetically Driven Jets From Accretion Disks: Nonsteady And Steady Solutions....Pages 511-512 Active Region Evolution and Flare Activity — A Case Study of Noaa 7260....Pages 515-516 Front Matter....Pages 411-411 Relationship Between Cold And Hot Post-Flare Loops And The Impact On The Reconnection Flare Model....Pages 517-518 Pseudo-Two-Dimensional Hydrodynamic Modeling of Flare Loops....Pages 519-520 Isolating the Footpoint Characteristics of a Solar Flare Loop....Pages 527-529 Coronal Loop Interactions Observed In Optical Emission Lines....Pages 531-532 Electric Currents, and Magnetic Shear Variations During Some Flares of M- and X-Class....Pages 533-534 Relations Between Filament Current Systems and Solar Flares....Pages 535-536 Magnetic Field Structure and Accelerated Electrons in a Gradual Microwave/Hard X-ray Flare....Pages 537-538 Hard X-ray And Microwave Observations of an Impulsive Burst on 1994 January 6....Pages 539-540 Imaging Spectra Of Hard X-Ray From The Footpoints Of Solar Impulsive Loop Flares....Pages 541-542 Nonthermal Emissions In The Hard X-Ray And Microwave Ranges From Flaring Loops....Pages 543-544 Hard and Soft X-Ray Images of an LDE Flare....Pages 545-546 Electron Acceleration Site of the 1992 Sep. 6 Flare....Pages 547-548 The Height Distribution of Hard X-Rays in Impulsive Solar Flares....Pages 549-550 A Solar Flare in the FeI 5324 Line on 24 June 1993....Pages 551-552 Are White-Light Flares Related to High-Energy Particles?....Pages 553-554 X-Ray Line Shift and Plasma Flow in Solar Flare....Pages 555-556 X-Ray Observations Of an Over-the-limb Solar Flare with Large Spectral Line Shifts....Pages 557-558 Dynamical Response of the Solar Atmosphere to Flare Heating....Pages 559-560 Effects of Non-Thermal Particles on the UV and Optical Spectra of Solar Flares....Pages 561-562 A Study of the Thermal/Nonthermal Electric Field Model Using Spectral and Spatial X-Ray Data from CGRO and Yohkoh....Pages 563-564 Front Matter....Pages 411-411 Energization of the 10–100 Kev Electrons in Solar Flares by Strongly-Driven Reconnection....Pages 565-566 Observations of the Creation of Hot Plasma in Solar Flares....Pages 567-568 Discovery of Sub-Second Brightenings in Solar Flares with the Nobeyama Radioheliograph....Pages 569-570 Gamma-Ray Spectral Characteristics of Solar Flares....Pages 571-572 Downward Beaming of Accelerated Particles in the 1991 November 15 Flare....Pages 573-574 High Energy Limit of Particle Acceleration in Solar Flares....Pages 575-575 Characteristics of Stellar Flares on EV Lac from a Long-Term Photometric Program....Pages 577-578 Maximum Energy Of Force-Free Magnetic Fields....Pages 579-580 A Kinetic Model of Magnetic Field Reconnection....Pages 581-582 Computer Simulations on the Spontaneous Fast Reconnection Mechanism....Pages 583-584 Numerical Simulation of Magnetic Reconnection in Eruptive Flares....Pages 585-586 Three Dimensional Simulation Study of the Magnetohydrodynamic Relaxation Process in the Solar Corona....Pages 587-588 Computer Simulation and Visulization of Solar Flares....Pages 589-590 Pinch Processes Near the Transition Region and Electron Bombardment of the Chromosphere in the Presence of Electsric Current....Pages 591-592 Alfvén Wave Proton Injection and Acceleration in Solar Flares....Pages 593-594 3D MHD Simulation of the Dynamic Current Injection Model of Loop Flares....Pages 595-596 Nonlinear Simulation Of Tearing Instability Of A Magnetic Arcade....Pages 597-598 Formation and Emergence of Current Loops in Weakly Ionized Plasmas....Pages 599-600 Formation of Current Loops Driven By The Kelvin-Helmholtz Instability....Pages 601-602 Simulation of a Cloud-Cloud Collision in an Electron-Positron Plasma....Pages 603-604 Front Matter....Pages 411-411 Cosmic Ray Chaos Requires New Physics....Pages 605-606 Solutions of the Hydromagnetic Equation with Localized and Uniform Resistivity....Pages 607-608 Large-Scale Active Coronal Phenomena in Yohkoh SXT Images....Pages 609-610 3D MHD Simulation of Magnetic Flux Tubes in Co-Rotating Coordinates....Pages 613-614 Distributions of the Magnetic Field Inclination in Sunspots....Pages 615-616 Dynamics of the Solar Granulation: Its Interaction with the Magnetic Field....Pages 617-618 A Model Of Magnetic Field On Supergranules....Pages 619-620 Solar Convection and Magneto-Convection....Pages 621-622 Triple-Dipole Model on the Large-Scale Magnetic Structure of the Sun....Pages 623-625 Solar Cycle Variation of the Rotation of the Large-Scale Magnetic Field of the Sun....Pages 627-628 Grand Minima in Solar Magnetic Activity....Pages 629-630 Spectral Imaging of AR Lac from 1981 to 1994....Pages 631-632 Two Mechanisms of a Current Sheet Creation in the Solar Corona....Pages 633-634 Back Matter....Pages 635-636 This volume presents the papers from a major international conference aimed at cross-linking research in the fields of solar and stellar activity. The Yohkoh satellite, with its spectacular views of solar coronal structures seen via their X-ray emission, provided the immediate motivation for the conference. How do these solar structures transcribe into their stellar counterparts; what insights can the more extreme stellar activity provide to guide the analysis of solar data? Coming four years after the launch of Yohkoh, this conference provided a good platform for displaying its discoveries. Longer-term variation associated with the 11-year solar cycle can also be seen clearly in the data presented. The new data strongly support many earlier interpretations of such magnetodynamic activity, but also provide some new and perplexing mismatches now stimulating new theoretical work