Lecture course on Astrophysical Dynamos profesor Axel Brandenburg

Lecture course on Astrophysical Dynamos profesor Axel Brandenburg

Zapraszamy na wykłady
Lecture course on Astrophysical Dynamos
które wygłosi
profesor Axel Brandenburg
16. i 17. stycznia 2008 r.
w Obserwatoriu m Astronomicznym Uniwersytetu Jagielloń skiego
ul. Orla 171 (Duża Sala)
16. stycznia (środa)
godz. 13:00 - 13:45
Introduction
a) Early self- sustained dynam os (Siemens, Herzenberg, Roberts)
b) Laboratory Dynamos: Riga, Karlsruhe, Cadarache
c) Large- scale versus small scale dynamos
d) Dynamos in simulations: forced, convection, MRI
e) Energetics in dynamos
f) Kazantsev spectru m: k +3 / 2 , inertial range: k - 3/2 or - 5/3
g) Dependence on magnetic Prandtl number
godz. 13:55 - 14:40
Pencil Code and dyna m o simulations
a) Code managem e nt, CVS, auto - tests
b) Roberts flow, varying kz
c) Turbulent alpha 2 dynam o in simulations
d) Theory of alpha 2 dynam o (first order smoot hing versus tau approximation)
godz. 15:20 - 16:05
Nonlinear large scale dyna m os (Part I)
a) Alpha quenching: exact results for low Rm
b) Catastrop hic quenching: early results
c) Magnetic helicity conservation in periodic domains
d) Inverse transfer (simple pheno m enology)
e) Slow saturation pheno m en o n (simple pheno me n ology)
godz. 16:15 - 17:00
Nonlinear large scale dyna m os (Part II)
a) The dynamical quenching model
b) Dynamos with shear (traveling waves, effect on magnetic helicity)
c) Open domains and magnetic helicity fluxes (Vishniac - Cho flux)
d) Simulations results
e) Results from dynamically quenched mean - field models
17. stycznia (czwartek)
godz. 11:00 - 11:45
Transpor t coefficients from simulations (Part I)
a) Simple approaches
b) Results for shear - flow turbulence and Galloway- Proctor flow
c) Test field method and results for Roberts flow
d) Refined results for Galloway - Proctor flow
e) Isotropic turbulence and depende nce on magnetic Reynolds number
godz. 12:00 - 12:45
Transpor t coefficients from simulations (Part II)
a) Scale- dependence, nonlocality, integral kernels for alpha
b) Shear - flow turbulence and shear - current effect
c) Incoherent alpha - Shear dynamos and incoherent shear - current dynamo s