Astrophysical Magnetohydrodynamics

6 Apr 2009, 08:00 → 10 Apr 2009, 18:00 Europe/Stockholm

Kiljavanranta Conference Centre, Finland

Anvar Shukurov (Newcastle University), Kandaswamy Subramanian (Inter-University Centre for Astronomy and Astrophysics), Maarit Korpi (Helsinki University)

→ Link to the more Detailed Editorial Note of the special issue in Astronomische Nachrichten.

A meeting on the occasion of the 50th birthday of Axel Brandenburg (Nordita, Stockholm, Sweden). The location has been chosen in Finland, where the academic career of Axel has started. The scope of the meeting covers the broad range of Axel's research interests, from planets to the Sun and stars, to galaxies, and to the Early Universe, with emphasis on the role and origin of magnetic fields, and on numerical experiments. Axel has published with about 130 coauthors. The purpose of the meeting is to bring together leading experts in these research areas, many of whom will inevitably -- but not exclusively -- be Axel's friends and coauthors.

The venue will be the Kiljavanranta Conference Centre located by the lake Sääksjärvi about 50 km from Helsinki (and 35 km from the Helsinki-Vantaa airport, and 10 km from the nearest town, Nurmijärvi). The Centre provides excellent working environment and attractive leisure facilities.

Monday, 6 April

09:30 → 10:15 Morning session 1

09:30 Introduction

Speaker: Dr Maarit Korpi (Observatory, University of Helsinki)

09:45 A new era for mean fields: test fields and tests

Speaker: Prof. Axel Brandenburg (NORDITA)

10:15 → 11:00 Coffee break

11:00 → 12:00 Morning session 2

11:00 Mean electromotive force proportional to mean flow in MHD turbulence

Speaker: Prof. Karl-Heinz Rädler (AIP)

11:30 The origin of our galactic magnetic field

Speaker: Prof. Russell Kulsrud (Princeton)

12:00 → 13:30 Lunch break

13:30 → 14:30 Afternoon session 1

13:30 Direct simulation of fossil fields in convective protostars

Speaker: Dr Rainer Arlt (AIP, Potsdam)

14:00 Star-in-a-box simulations of the solar dynamo

Speaker: Dr Boris Dintrans (LAOMP, Toulouse)

14:30 → 15:00 Coffee break

15:00 → 16:30 Afternoon session 2

15:00 Dynamics of the solar magnetic field from SOHO/MDI

Speaker: Dr Elena Benevolenskaya (Stanford)

15:30 Large-scale dynamos in local models of turbulent convection

Speaker: Dr Petri Käpylä (Observatory, University of Helsinki)

16:00 Solar fluctuative magnetic field after data concerning sunspots violating the Hale polarity law

Speaker: Prof. Dmitry Sokoloff (Moscow State University)

16:30 → 17:15 Discussion session

17:30 → 19:00 Dinner

19:00 → 21:30 Sauna evening nearby the lake Sääksjärvi

Tuesday, 7 April

09:30 → 10:30 Morning session 1

09:30 Supersonic turbulence and dynamo action

Speaker: Åke Nordlund

10:00 Memory effects in turbulent transport

Speaker: Dr Alexander Hubbard (NORDITA)

10:30 → 11:00 Coffee break

11:00 → 12:00 Morning session 2

11:00 Flux rope dynamos

Speaker: Prof. Anvar Shukurov (School of Mathematics and Statistics, Newcastle University, U.K.)

11:30 Simple laminar dynamo solutions in finite volumes

Speaker: Dr David Moss (Manchester University)

12:00 → 13:30 Lunch break

13:30 → 14:30 Afternoon session 1

13:30 Symmetry breaking in physics: The 2008 Nobel Awards

Speaker: Prof. Paul Hoyer (University of Helsinki)

14:00 On global conserved quantities in spectral simulations of MHD turbulence

Speaker: Dr Chi-Kwan Chan (ITC Cambridge)

14:30 → 15:00 Coffee break

15:00 → 16:30 Afternoon session 2

15:00 Three kinds on non-helical mean-field dynamos

Speaker: Prof. Igor Rogachevskii (Ben-Gurion University of the Negev)

15:30 Effect of turbulent convection on differential rotation and formation of magnetic structures

Speaker: Prof. Nathan Kleeorin (Ben Gurion)

16:00 Turbulence at the Sun's surface

Speaker: Prof. Michel Rieutord (LAOMP, Toulouse)

16:30 → 17:15 Discussion

18:30 → 21:30 Conference dinner

Wednesday, 8 April

10:00 → 10:30 Morning session 1

10:00 Dynamo action in linear shear flows

Speaker: Dr Sridhar S. (RRI, Bangalore)

10:30 → 11:00 Coffee break

11:00 → 12:00 Morning session 2

11:00 Comparisons and connections between large scale dynamo theory and accretion disk theory

Speaker: Prof. Eric Blackman (Rochester)

11:30 Dynamos and magnetic field detachement in thermally unstable interstellar flows

Speaker: Dr Maarit Korpi (Observatory, University of Helsinki)

12:00 → 13:30 Lunch break

13:30 → 14:30 Afternoon session 1

13:30 Numerical global simulations of Taylor instability in jets

Speaker: Dr Alfio Bonanno (Catania)

14:00 On the saturation of the non-ideal magnetorotational instability via parasitic instabilities

Speaker: Dr Martin Pessah (IAS, Princeton)

14:30 → 15:00 Coffee break

15:00 → 16:30 Afternoon session 2

15:00 Structure of Thin Accretion Disc Around Magnetized Stars

Speaker: Dr Solomon Tessema (Gothenburg)

15:30 Hall MHD in a strong magnetic field

Speaker: Dr Daniel Gomez (Buenos Aires)

16:00 Stability of the magnetospheric boundary in long-period X-ray pulsars

Speaker: Dr Nazar Ikshanov (NSSTC)

16:30 → 17:15 Discussion session

17:30 → 19:00 Dinner

19:30 → 20:30 Evening lecture

19:30 On the early days of dynamo theory

Speaker: Prof. Karl-Heinz Rädler (AIP)

Thursday, 9 April

09:30 → 10:30 Morning session 1

09:30 Simulations in spherical wedge domains: recent results

Speaker: Prof. Reza Tavakol (Queen Mary, London)

10:00 New experiments to study nonaxisymmetric magnetic instabilities

Speaker: Prof. Guenther Ruediger (AIP, Potsdam)

10:30 → 11:00 Coffee break

11:00 → 12:00 Morning session 2

11:00 Magnetic fields near the Galactic center

Speaker: Dr Katia Ferriere (LAOMP, Toulouse)

11:30 Magnetic field generation in the early universe

Speaker: Prof. Subramanian Kandaswamy (IUCAA)

12:00 → 13:30 Lunch break

13:30 → 14:30 Afternoon session 1

13:30 Predicting turbulent stresses in a local disk model

Speaker: Ms Anne Liljeström (University of Helsinki)

14:00 Growth of magnetic fields in clusters of galaxies

Speaker: Mr Paul Sutter (Univ. of Illinois)

14:30 → 15:00 Coffee break

15:00 → 16:30 Afternoon session 2

15:00 Galaxies as building blocks for magnetic fields in the large scale structures of the Universe

Speaker: Dr Yohan Dubois (Univ. of Oxford)

15:30 Bifurcation structure of nonlinear dynamos in torus geometry

Speaker: Dr John Brooke (Manchester University)

16:00 Kinematic dynamo simulations in cylindrical geometry

Speaker: Dr Andre Giesecke (Dresden-Rossendorf)

16:30 → 17:15 Discussion session

17:30 → 19:00 Dinner

19:30 → 20:30 Evening lecture

19:30 Improving helmet protection against traumatic brain injury: a physics perspective

Speaker: Prof. Eric Blackman (Rochester)

Friday, 10 April

09:30 → 11:00 Morning session 1

09:30 Stellar magnetic fields: observations and nonlinear modelling

Speaker: Ms Marjaana Lindborg (Observatory, University of Helsinki)

09:50 Rapid dynamo saturation without net small-scale helicity losses

Speaker: Mr Simon Candelaresi (NORDITA)

10:10 Gravitational stability of accretion discs

Speaker: Ms Fazeleh Khajenabi (UCD)

10:30 The alpha effect with imposed and dynamo-generated magnetic fields

Estimates for the nonlinear alpha effect in helical turbulence are presented using two different approaches where a uniform magnetic field is applied either to the actual field, or where separate evolution equations are solved for a set of different test fields. Both approaches agree for stronger fields, but there are apparent discrepancies for weaker fields that can be explained by the influence of dynamo-generated meso-scale magnetic fields. Examples are discussed where with an imposed magnetic field the alpha effect is either drastically overestimated, or drastically underestimated compared with the kinematic value. It is demonstrated that the kinematic value can be estimated correctly by reseting the magnetic field in regular time intervals.

Speaker: Fabio Del Sordo (NORDITA)

11:00 → 11:30 Coffee break

11:30 → 12:00 Closing discussion

12:00 → 13:30 Lunch