ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES Volume 358 SOLAR POLARIZATION 4 Proceedings of a meeting held in Boulder, Colorado, USA 19-23-September2005 Edited by R. Casini High Altitude Observatory, National Center for Atmospheric Research Boulder, Colorado, USA and f B. W. Lites High Altitude Observatory, National Center for Atmospheric Research Boulder, Colorado, USA SAN FRANCISCO
Contents Preface Participants Conference Photograph xiii xvii xxiii Session 1. Photospheric Magnetism Signatures of Penumbral Magnetic Fields at Very High Spatial «Resolution 3 K. Langhans The Micro-Structure of a Sunspot Penumbra 13 J. Sanchez Almeida The Uncombed Penumbra 19 J. M. Borrero, M. Rempel, and S. K, Solanki Inversion of Visible and IR Stokes Profiles in Sunspots 25 D. Cabrera Solana, L. R. Bellot Rubio, C. Beck, and J. C. del Toro Iniesta Penumbral Moving Magnetic Features 31 M. J. Penn, S. A. Jaeggli, C. J. Henney, S. Luszcz, and S. R. Walton Internetwork Magnetic Field Distribution from Simultaneous Fei 1.5 nm and Fei 630 nm Observations 36 M. J. Martinez Gonzalez, M. Collados, and B. Ruiz Cobo On the Determination of Magnetic Field Strength and Flux in Inter-Network 42 E. Khomenko and M. Collados Magnetic Fields of the Quiet Sun: Distribution of Field Strengths 48 I. Dominguez Cerdena, J. Sanchez Almeida, and F. Kneer Quiet-Sun Magnetism Seen with a Mn Line: Km-Sized Magnetic Structures 54 A. Lopez Ariste, J. C. Ramirez Velez, S. Tomczyk, R. Casini, and M. Semel
vi_ Contents G - B a n d Bright Points a n d P h o t o s p h e r i c M a g n e t i c Fields... 61 L. Bharti, R. Jain, C. Joshi, and S. N. A. Jaaffrey Multi-Line Spectro-Polarimetry of Filaments 68 K. S. Balasubramaniam, K. Sankarasubramanian, and A. A. Pevtsov Polarimetric Observations of the Formation of a G-Band Bright Point 72 C. Beck, W. Schmidt, L. R. Bellot Rubio, R. Schlichenmaier, P. Siitterlin, and B. W. Lites Photospheric D y n a m i c M o d e l of Magnetic Reconnection... 76 F. Berrilli, B. Viticchie, D. Del Mow, and A. Egidi Proper Motions in Sunspot Penumbrae: Signs of Convection. 80 J. A. Bonet, I. Marquez, and J. Sanchez Almeida 3D Reconstruction of Photospheric Velocity Fields Inside a Magnetic Network Cell 84 D. Del Mow, S. Giordano, and F. Berrilli Quiet-Sun Magnetic Fields: Simultaneous Inversion of Visible and IR Spectro-Polarimetric Observations 88 I. Dominguez Cerdena, J. Sanchez Almeida, and F. Kneer SOLIS-VSM Solar Vector Magnetograms' 92 C. J. Henney, C. U. Keller, and J. W. Harvey The Evershed Effect with C'2 Angular Resolution 96 I. Marquez, J. A. Bonet, J. Sanchez Almeida, and I. Dominguez Cerdena Systematic Errors in Dopplergrams of Active Regions and Their Correction 100 R. Wachter and S. P. Rajaguru Session 2. Radiative Transfer Methods and Inversion Techniques Stokes Inversion Techniques: Recent Advances and New Challenges 107 L. R. Bellot Rubio UNNOFIT Inversion of Spectro-Polarimetric Maps Observed with THEMIS 119 V. Bommier, E. Landi Degl'Innocenti, M. LandolS, and G. Molodij Interpretation of the Second Solar Spectrum of the Sr I 4607 A Line Observed at THEMIS and Pic-du-Midi 120 M. Derouich, V. Bommier, J.-M. Malherbe, E. Landi Degl'Innocenti, G. Molodij, and S, Sahal-Brechot Polarized Spectral Line Formation in Turbulent Magnetic Fields: The Zeeman and Hanle Effects 126 H. Frisch, M. Sampoorna, and K. N. Nagendra
Contents vii Major Effects of Line Asymmetries in Solar Magnetic Field Measurements from Simultaneous Multi-Wavelength Observations 132 G. Molodij and J. Rayrole The Characteristic Length Scale of the Magnetic Fluctuation in a Sunspot Penumbra: A Stochastic Polarized Radiative Transfer Approach 137 T. A. Carroll and J. Staude Magnetic Field Vector Retrieval with HMI.... 144 J. M. Borrero, S. Tomczyk, A. A. Norton, T. Darnell, J. Schou, P. Scherrer, R. I. Bush, and Y. Lui Multigrid Methods for Polarized Radiative Transfer 148 J. Stepan Session 3. New Solar Polarimeters and Techniques Tunable Narrow-Band Filter for Imaging Polarimetry 155 A. Feller, A. Boiler, and J. O. Stenflo 4 ' J The Solar Ultraviolet Magnetograph Investigation: Polarization Properties 161 E. A. West, K. Kobayashi, G. A. Gary, and J, M. Davis Solar Spectro-Polarimetry at Pic-du-Midi/LJR 167 J. Arnaud, T. Roudier, J.-M. Malherbe, and J. Moity ; Magnetic Field Measurements in Flare Loops and CMEs.... 173 T. S. Bastian First Steps Towards the Electronic Inversion of the Radiative Transfer Equation 177 J. L. Castillo Lorenzo, D. Orozco Suarez, L. R. Bellot Rubio, A. C. Lopez Jimenez, and J. C. del Toro Iniesta Civ Vacuum Ultraviolet Fabry-Perot Interferometers for Transition-Region Magnetography 181 G. A. Gary, E. A. West, D. E. Rees, M. Zukic, P. Herman, and J. Li High-Precision Imaging Polarimetry in the Ha line 185 Y. Hanaoka Magnetic Field Diagnostic Capability of Solar-B/SOT: Filtergraph Instrument 189 K. Ichimoto, Y. Suematsu,T. Shimizu, Y. Katsukawa, S. Tsuneta, T. D. Tarbell, R. A. Shine, C. M. Hoffmann, A. M. Title, B. W. Lites, D. F. Elmore, and K. V. Streander Spectral Line Selection for HMI 193 A. A. Norton, J. D. Pietarila Graham, R. K. Ulrich,, J. Schou, S. Tomczyk, Y. Liu, B. W. Lites, A. Lopez Ariste, R. I. Bush, H. Socas-Navarro, and P. H. Scherrer
viii Contents Milne-Eddington Response Functions and Their Applications. 197 D. Orozco Suarez, L. R. Bellot Rubio, and J. C. del Toro Iniesta The Diffraction Limited Spectro-Polarimeter 201 K. Sankarasubramanian, B. Lites, C. Gullixson, D. Elmore, S. Hegwer, K. Streander, T. Rimmele, S. Fletcher, S. Gregory, and M. Sigwarth The Ban 4554/H/3 Imaging Polarimeter for the Dutch Open Telescope 205 F. Snik, F. C. M. Bettonvil, A. P. L. Jagers, R. H. Hammerschlag, R. J. Rutten, and C. U. Keller Large Field-of-View KD*P Modulator for Solar Polarization Measurements 209 E. A. West and G. A. Gary Session 4. Atomic Spectro-Polarimetry Second Solar Spectrum: A Brief Overview 215 J. O. Stenflo Polarimetry of the Second Solar Spectrum in the UVB 225 A. Gandorfer and D. Gisler Second Spectrum of Na I D x Observed with THEMIS 231 V. Bommier and G. Molodij Polarized Scattering in Strong Chromospheric Lines: Theory and Its Confrontation with Observations 237 D. M. Fluri, R. Holzreuter, and J. O. Stenflo Session 5. Theory of Collisional Polarization Semi-Classical Collision Formalism with Energy and Momentum Transfer 245 V. Bommier Calculation of Depolarization and Polarization Rates by Isotropic Collisions with Neutral Hydrogen 256 M. Derouich Session 6. Laboratory Experiments and Molecular Spectro- Polarimetry The Hanle Effect in Atomic and Molecular Lines: A New Look at the Sun's Hidden Magnetism 269 J. Trujillo Bueno, A. Asensio Ramos, and N. Shchukina
Contents ix Polarizability Factors for Molecular Bands 293 E. Landi Degl'Innocenti Theory, Observation, and Modeling, of the. Zeeman and Paschen- Back Effects in Molecular Lines 301 A. Asensio Ramos Hanle Effect in the Paschen-Back Regime 311 A. I. Shapiro, D. M. Fluri, S. V. Berdyugina, and J. O. Stenflo Multi-Line Determination of the Turbulent Magnetic Field from the Second Solar Spectrum of MgH 317 V. Bommier, E. Landi Degl'Innocenti, and G. Molodij Three-Dimensional Radiative Transfer Modeling of the Scattering Polarization in MgH Lines. 318 A. Asensio Ramos and J. Trujillo Bueno Spectro-Polarimetry of a Sunspot in Atomic and Molecular Lines with THEMIS 319 J. Arnaud, S. V. Berdyugina, D. M. Fluri, N. Afram, S. K. Solanki, and N.-E. Raouafi Laboratory Experiment for Polarized Scattering at Potassium Vapor 323 C. Thalmann, J. O. Stenflo, A. Feller, and A. Cacciani The Molecular Paschen-Back Effect 329 S. V. Berdyugina, D. M. Fluri, and S. K. Solanki Session 7. Stellar Spectro-Polarimetry Spectro-Polarimetry of Cool Stars 335 P. Petit Spectro-Polarimetry of Magnetic Hot Stars 345 O. Kochukhov Multi-Line Spectro-Polarimetry of Stellar Magnetic Fields Using Principal Components Analysis 355 M. Semel, D. E. Rees, J. C. Ramirez VSlez, M. J. Stift, and F. Leone ESPaDOnS: The New Generation Stellar Spectro-Polarimeter. Performances and First Results 362 J.-F. Donati, C. Catala, J. D. Landstreet, P. Petit, and the ESPaDOnS Team Investigation of the Magnetic Field Characteristics of Herbig Ae/Be Stars: Discovery of the Pre-Main Sequence Progenitors of the Magnetic Ap/Bp Stars 369 G. A. Wade, D. Drouin, S. Bagnulo, J. D. Landstreet, E. Mason, J. Silvester, E. Alecian, T. Bohm, J.-C. Bouret, C. Catala, J.-F. Donati, C. Folsom, and K. Bale
x - Contents Molecular Diagnostics of the Internal Structure of Starspots and Sunspots 375 N. Afram, S. V. Berdyugina, D. M. Fluri, S. K. Solanki, A. Lagg, P. Petit, and J. Arnaud Detection of the Molecular Zeeman Effect in Circular Polarization on Cool Active Stars 381 S. V. Berdyugina, P. Petit, D. M. Fluri, N. Afram, and J. Arnaud Applied Doppler Imaging: Can Magnetic Activity of IM Pegasi Affect the Gravity Probe B Mission? 385 S. V. Berdyugina and S. C. Marsden Rotation and Chemical Abundances of Magnetic Ap/Bp Members in the Open Cluster NGC 6475 389 C. P. Folsom, G. A. Wade, S. Bagnulo,, andj. D. Landstreet A Spectro-Polarimetric Survey of the Coolest Magnetic Ap Stars 393 JV. Johnson, G. A. Wade, A. Allen, C. Folsom, M. Welland, M. Auriere, J.-F. Donati, S. Jeffers, F. Lignires, S. Marsden, D. Mouillet, F. Paletou, P. Petit, N. Toque, S. Bagnulo, J. D. Landstreet, T. Liiftinger, and T. Ryabchikova Magnetic Field Modeling of 78 Vir from the Analysis of Cm Lines 397 V. R. Khalack and G. A. Wade The Magnetic Activity of Young Suns: Magnetic Topologies and Differential Rotation of F- and G-Dwarfs 401 S. C. Marsden, M. W. Mengel, J.-F. Donati, B. D. Carter, M. Semel, and P. Petit PCA Technique Applied to the Detection of ZDI Circular Polarization in Solar-Type Stars 405 J. C. Ramirez Velez, M. Semel, M. J. Stift, and F. Leone An Evolutionary Study of Magnetic Ap Stars in 4 Northern Open Clusters 409 J. Silvester, G. A. Wade, and D. A. Hanes Possible Detection of Weak Magnetic Fields in Two White Dwarfs, Including the Pulsating WD 1647+591 413 G. Valyavin, S. Bagnulo, S. Fabrika, Inwoo Han, D. Monin, A. Reisenegger, and G. A. Wade Session 8. Chromospheric Electro-Magnetism Chromospheric Magnetism 419 J. W. Harvey The Effect of Turbulent Electric Fields on the Scattering Polarization of Hydrogen Lines 429 R. Casini and R. Manso Sainz
Contents xi Measuring the Magnetic Vector with the He I 10830 A Line: A Rich New World 431 S. K. Solanki, A. Lagg, R. Aznar Cuadrado, D. Orozco Suarez, M. Collados, T. Wiegelmann, J. Woch, C. Sasso, and N. Krupp Supersonic Downflows in the Vicinity of a Solar Pore 437 A. Lagg, J. Woch, S. K. Solanki, and A. Gandorfer Inference of the Magnetic Field in Spicules from Spectro- Polarimetry of He I D 3 443 A. Lopez Ariste and R. Casini T h e H a n l e a n d Z e e m a n E f f e c t s i n S o l a r S p i c u l e s... -r... 4 4 8 R. Ramelli, M. Bianda, L. Merenda, and J. Trujillo Bueno Spectro-Polarimetric Observations of Filaments in Ha and He I D 3 454 M. Bianda, R. Ramelli, J. Trujillo Bueno, and J. O. Stenflo The Hanle and Zeeman Effects in the Ba II D 2 line 459 L. Belluzzi, J. Trujillo Bueno, and E. Landi Degl'Innocenti Oscillations and Wave Propagation in Different Solar Magnetic, Features 465 R. Centeno, M. Collados, and J. Trujillo Bueno Spectro-Polarimetry of Solar Prominences 471 R. Ramelli, M. Bianda, J. Trujillo Bueno, L. Merenda, and J. O. Stenflo Author Index 475