Theory and modelling of polarisation in astrophysics

group photo 2n

Dates: 5-8 May 2014

Location: Vila Lanna, Prague, Czech Republic



This was the first meeting of the Working Group 2 (WG2) of the COST Action MP 1104

The meeting aimed at in-depth discussions between researchers studying the complex physics of the interaction of radiation and matter in magnetised plasmas, the generation and transfer of polarized radiation, and those developing and implementing efficient numerical methods for making feasible realistic numerical simulations.

The following topics were discussed:

  1. Theories of spectral line polarisation
  2. Physical mechanisms that produce/modify polarised radiation
  3.  Radiative transfer
  4. Self-consistent modeling of polarisation in astrophysical plasmas
  5. From the observed polarisation to the physical conditions



Javier Trujillo Bueno (co-chair, IAC, Spain)
Jiri Stepan (co-chair, AIAS, Czech Republic)
Luca Belluzzi (IRSOL, Switzerland)
Veronique Bommier (Observatoire de Paris, France)
Roberto Casini (HAO, USA)
Michal Dovciak (AIAS, Czech Republic)
Rico Ignace (ETSU, USA)
Oleg Kochukhov (Uppsala University, Sweden)
Egidio Landi Degl'Innocenti (Universita' di Firenze, Italy)
Octavio Roncero Villa (Instituto de Fisica Fundamental (C.S.I.C.), Spain)

Daphne Stam (SRON Netherlands Institute for Space Research, Netherlands)



Jiri Stepan (Chair, AIAS, Czech Republic)

Michal Dovciak (AIAS, Czech Republic)
Stanislav Gunar (AIAS, Czech Republic)
Petr Heinzel (AIAS, Czech Republic)
Jan Jurcak (AIAS, Czech Republic)




Session 1

Roberto Casini :  A new formulation of spectral line polarization with partial frequency redistribution

Veronique Bommier:  XTAT, a new multilevel-multiline polarized radiative transfer code with PRD

Egidio Landi Degl'Innocenti:  Relaxation phenomena in hyperfine structure multiplets due to collisions with neutral perturbers


Session 2

Luca Belluzzi:  A possible mechanism for understanding the enigmatic scattering polarization signals observed in the solar Ba II and Na I D1 lines

Sowmya Krishnamurthy: Paschen-Back effect in hyperfine structure states of an atom including the effects of partial frequency redistribution

Octavio Roncero:  Depolarizing collisions of neutral and singly ionized alkaline earths with hydrogen atoms

Cristina Sanz Sanz:  LS depolarizing transitions in A+H collisions: a diabatization approach

Thiem Hoang: Grain Alignment by Radiative Torques: Theory and Implications for Modeling Dust Polarization

Richard Ignace:  Continuum Polarization in Circumstellar Media

Michal Dovčiak:  Relativistic effects on polarization properties of radiation emitted in strong gravity

Session 3

Helene Frisch: The diffusion approximation for Rayleigh scattering

Juris Freimanis: Polarized radiative transfer equation in the most important curvilinear coordinate systems

Ghislain R. Franssens:  Mueller matrices and their role in the Vectorial Radiative Transfer model

Frederic Marin: STOKES - A Monte Carlo radiative transfer code for polarization modeling

Marko Stalevski: Modeling AGN polarization with Monte Carlo radiative transfer code SKIRT

L. S. Anusha: Multi-dimensional radiative transfer for modeling the chromospheric polarized spectrum

Session 4

Jiří Štěpán:  Multilevel 3D non-LTE modeling with the code PORTA

H. D. Supriya:  Modeling of the center to limb variation of linear polarization in the spectrum of the Ca I 4227 A line

Javier Trujillo Bueno: Scattering Polarization in UV Lines for Probing the Chromosphere and Transition Region of the Sun

Tanausú del Pino Alemán:  Multilevel Modeling of Scattering Line Polarization with the Weak Anisotropy Approximation


Session 5.1

Jan Stenflo: Resolution-independent diagnostics of magnetic fields: choice of observables, suppression of model dependence, elimination of noise bias, scaling behavior of ensemble averages

María J. Martínez González: Anomalous Circular Polarization Profiles in the He I 1083.0 nm Multiplet from Solar Spicules

Ivan Milic: Effects of inhomogeneities and velocity fields on scattering polarization in solar prominences

Andrés Asensio Ramos: Learning from spectropolarimetric observations


Session 5.2

Oleg Kochukhov:  Multi-line polarisation analysis of stellar spectra

Nicolas Fabas: A study of the atmospheric dynamics and magnetic fields in Mira stars through full-Stokes spectropolarimetry

Nataliia Shchukina:  Continuum polarization of stars as a result of occultation by transiting exoplanets

Session 5.3

Luka C. Popovic: Estimation of AGN super-massive black hole masses using spectro-polarometric observations

Lachezar Filipov:  Polarization radiation from the accretion disk and proto-planetary formation mechanisms and application diagnostics processes in them

Sergio Fabiani: Future prospects for solar flare X-ray polarimetric missions

Sebastian Kiehlmann: Discriminating stochastic from deterministic EVPA swing mechanisms in AGN jets

Ioannis Myserlis: Multi-frequency linear and circular radio polarization


List of participants :

  1. Dr. Andres Asensio Ramos
  2. Mr. Ivan Milic
  3. Dr. Marko Stalevski
  4. Mr. Ioannis Myserlis
  5. Dr. Octavio Roncero
  6. Dr. Veronique Bommier
  7. Dr. Ghislain Franssens
  8. Mr. Ernest Alsina
  9. Mr. Tanausu del Pino Alemán
  10. Dr. Sergio Fabiani
  11. Dr. Cristina Sanz Sanz
  12. Prof. Nataliia Shchukina
  13. Prof. Luka Popovic
  14. Dr. Oleg Kochukhov
  15. Prof. Javier Trujillo Bueno
  16. Dr. Juris Freimanis
  17. Dr. Lachezar Filipov
  18. Dr. Roberto Casini
  19. Mrs. Supriya Dayananda
  20. Prof. Jan Stenflo
  21. Dr. Anusha Bhasari
  22. Dr. Frederic Marin
  23. Mr. Adam Tichy
  24. Dr. Jiri Stepan
  25. Dr. Michal Dovčiak
  26. Mr. Sebastian Kiehlmann
  27. Dr. Luca Belluzzi
  28. Mrs. Sowmya Krishnamurthy
  29. Dr. Thiem Hoang
  30. Prof. Richard Ignace
  31. Dr. Helene Frisch
  32. Dr. Jan Jurčák
  33. Prof. Petr Heinzel
  34. Dr. Stanislav Gunár
  35. Dr. Hervé Lamy