Tuesday, 09 February
Generation of Alfven Waves by Magnetic Reconnection
http://www.arxiv.org/abs/1002.1360Hiromitsu Kigure, Kunio Takahashi, Kazunari Shibata, Takaaki Yokoyama, Satoshi Nozawa
29 pages, 17 figures
In this paper, results of 2.5-dimensional magnetohydrodynamical simulations are reported for the magnetic reconnection of non-perfectly antiparallel magnetic fields.
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09 02 10 - 08:49 |
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Monday, 08 February
Numerical Models of Sgr A*
http://www.arxiv.org/abs/1002.1261M. Moscibrodzka, C.F. Gammie, J. Dolence, H. Shiokawa, P.K. Leung
To appear in "The Galactic Center: A Window on the Nuclear Environment of Disk Galaxies", ed. Mark Morris, Daniel Q. Wang and Feng Yuan
We review results from general relativistic axisymmetric magnetohydrodynamic simulations of accretion in Sgr A*.
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08 02 10 - 14:16 |
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The Density Variance Mach Number Relation in the Taurus Molecular Cloud
http://www.arxiv.org/abs/1002.1239Chris Brunt
8 pages, 9 figures. Accepted for publication in A&A
Supersonic turbulence in molecular clouds is a key agent in generating density enhancements that may subsequently go on to form stars.
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08 02 10 - 14:16 |
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Numerical Simulation of Excitation and Propagation of Helioseismic MHD Waves in Magnetostatic Models of Sunspots
http://www.arxiv.org/abs/1002.1117K. Parchevsky, A. Kosovichev, E. Khomenko, V. Olshevsky, M. Collados
17 pages, 9 figures
We present comparison of numerical simulations of propagation of MHD waves,excited by subphotospheric perturbations, in two different ("deep" and "shallow") magnetostatic models of the sunspots.
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08 02 10 - 14:13 |
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Wednesday, 03 February
Low magnetic-Prandtl number flow configurations for cold astrophysical disk models: speculation and analysis
http://www.arxiv.org/abs/1002.0506O. M. Umurhan
To Appear in Astronomy and Astrophysics
Simulations of astrophysical disks in the shearing box that are subject to the magnetorotational instability (MRI) show that activity appears to be reduced as the magnetic Prandtl number (Pm) is lowered.
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03 02 10 - 14:37 |
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Three-Dimensional Propagation of Magnetohydrodynamic Waves in Solar Coronal Arcades
http://www.arxiv.org/abs/1002.0469S. Rial, I. Arregui, J. Terradas, R. Oliver, J.L. Ballester
38 pages, 50 figures
We numerically investigate the excitation and temporal evolution of oscillations in a two-dimensional coronal arcade by including the three-dimensional propagation of perturbations.
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03 02 10 - 14:36 |
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The origin and propagation of variability in the outflows of long duration gamma-ray bursts
http://www.arxiv.org/abs/1002.0361Brian J. Morsony, Davide Lazzati, Mitchell C. Begelman
16 pages, 12 figues, submitted to ApJ
We present the results of hydrodynamical simulations of gamma-ray burst jets propagating through their stellar progenitor material and subsequently through the surrounding circumstellar medium.
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03 02 10 - 14:34 |
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Monday, 01 February
Magnetic Connection Model for Launching Relativistic Jets from a Kerr Black Hole
http://www.arxiv.org/abs/1001.5434Ioana Dutan (Max-Planck-Institut fuer Radioastronomie, Bonn)
12 pages, 10 figures, submitted to MNRAS
We present an alternative model for launching relativistic jets in active galactic nuclei (AGN) from an accreting Kerr black hole (BH) by converting the accretion disc energy into jet energy, when the rotational energy of the BH is transferred to the inner disc by closed magnetic field lines which connects the BH to the disc (BH-disc magnetic connection).
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01 02 10 - 09:34 |
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Wednesday, 27 January
A Toomre-like stability criterion for the clumpy and turbulent interstellar medium
http://www.arxiv.org/abs/1001.4732Alessandro B. Romeo, Andreas Burkert, Oscar Agertz
Submitted to MNRAS
We explore the gravitational instability of clumpy and turbulent gas discs, taking into account the Larson-type scaling laws observed in giant molecular clouds (GMCs) and HI, as well as more general scaling relations.
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27 01 10 - 08:54 |
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Tuesday, 26 January
Equivalence of polynomial conjectures in additive combinatorics
http://www.arxiv.org/abs/1001.3356Shachar Lovett
We study two conjectures in additive combinatorics.
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26 01 10 - 08:13 |
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Finite Larmor Radius Effects on Weakly Magnetized, Dilute Plasmas
http://www.arxiv.org/abs/1001.4408Ebru Devlen, E. Rennan Pekünlü
7 pages, 4 figures. Accepted for publication in MNRAS
We investigate the stability properties of a hot, dilute and differentially rotating weakly magnetized plasma which is believed to be found in the interstellar medium of galaxies and protogalaxies and in the low-density accretion flows around some giant black holes like the one in the Galactic center.
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26 01 10 - 08:12 |
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The Accretion Disc Dynamo in the Solar Nebula
http://www.arxiv.org/abs/1001.4378A.R. King, J.E. Pringle
MNRAS, accepted
The nearest accretion disc to us in space if not time was the protosolar nebula.
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26 01 10 - 08:11 |
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Nonlinear propagation of Alfven waves driven by observed photospheric motions: Application to the coronal heating and spicule formation
http://www.arxiv.org/abs/1001.4307Takuma Matsumoto, Kazunari Shibata
We have performed MHD simulations of Alfven wave propagation along an open flux tube in the solar atmosphere.
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26 01 10 - 08:11 |
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A Self-Consistent Treatment of the Electromotive Force in Magnetohydrodynamics for Large Diffusivities
http://www.arxiv.org/abs/1001.4398A. Courvoisier, D.W. Hughes, M.R.E. Proctor
Submitted to Astron. Nachr
The coupled equations that describe the effect of large-scale magnetic and velocity fields on forced high-diffusivity magnetohydrodynamic flows are investigated through an extension of mean field electrodynamics.
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26 01 10 - 08:11 |
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Relativistic expansion of a magnetized fluid
http://www.arxiv.org/abs/1001.4209K.N. Gourgouliatos, N. Vlahakis
17 pages, 6 figures, accepted by Geophysical and Astrophysical Fluid Dynamics
We study semi-analytical time-dependent solutions of the relativistic magnetohydrodynamic (MHD) equations for the fields and the fluid emerging from a spherical source.
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26 01 10 - 08:10 |
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Some Properties of the Kinetic Energy Flux and Dissipation in Turbulent Stellar Convection Zones
http://www.arxiv.org/abs/1001.4138Casey Meakin, David Arnett
Refereed Conference Proceeding, HELAS Workshop on 'Synergies between solar and stellar modelling', Rome, June 2009, to be published in Astrophys. Space Sci
We investigate simulated turbulent flow within thermally driven stellar convection zones.
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26 01 10 - 08:09 |
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Vorticity of IGM Velocity Field on Large Scales
http://www.arxiv.org/abs/1001.4127Weishan Zhu, Long-Long Feng, Li-Zhi Fang
27 pages, 10 figures, accepted for publication in ApJ
We investigate the vorticity of the IGM velocity field on large scales with cosmological hydrodynamic simulation of the concordance model of LCDM.
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26 01 10 - 08:07 |
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Sunday, 24 January
Magnetohydrodynamics of superfluid and superconducting neutron star cores
http://www.arxiv.org/abs/1001.4046K. Glampedakis, N. Andersson, L. Samuelsson
26 pages, 1 eps figure
Mature neutron stars are cold enough to contain a number of superfluid and superconducting components.
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24 01 10 - 22:47 |
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On internal wave breaking and tidal dissipation near the centre of a solar-type star
http://www.arxiv.org/abs/1001.4009A.J. Barker, G.I. Ogilvie
22 pages, 10 figures, accepted in MNRAS, abstract shortened (!)
We study the fate of internal gravity waves, which are excited by tidal forcing by a short-period planet at the interface of convection and radiation zones, approaching the centre of a solar-type star.
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24 01 10 - 22:46 |
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On the role of supernovae-driven turbulence in the feeding of supermassive black holes
http://www.arxiv.org/abs/1001.3883Alexander Hobbs, Sergei Nayakshin, Chris Power, Andrew King
19 pages, 17 figures. Submitted to MNRAS
It has long been recognised that the main obstacle to accretion of gas onto supermassive black holes (SMBHs) is large specific angular momentum.
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24 01 10 - 22:43 |
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Gas circulation and galaxy evolution
http://www.arxiv.org/abs/1001.3879Filippo Fraternali (University of Bologna)
12 pages, 5 figures. Invited review at the conference "Hunting for the Dark: The Hidden Side of Galaxy Formation", Malta, 19-23 Oct. 2009. Eds. V.P. Debattista and C.C. Popescu, AIP Conf. Ser
Galaxies must form and evolve via the acquisition of gas from the intergalactic environment, however the way this gas accretion takes place is still poorly understood.
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24 01 10 - 22:42 |
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Thursday, 21 January
Rotational Mixing and Lithium Depletion
http://www.arxiv.org/abs/1001.3864M. H. Pinsonneault
6 pages, 1 figure, to appear in proceedings of IAU Symp. 268, in press
I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time.
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21 01 10 - 23:24 |
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Linear magnetosonic waves in solar wind flow tubes
http://www.arxiv.org/abs/1001.3823Suresh Chandra, S.V. Shinde, P.G. Musrif, Monika Sharma
4 pages
Nakariakov et al.
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21 01 10 - 23:24 |
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Two-dimensional hydrodynamical simulation of hot accretion flows with radiative cooling
http://www.arxiv.org/abs/1001.3571Feng Yuan (SHAO), Defu Bu (SHAO)
9 pages, 9 figures; submitted to MNRAS
The most important finding of two-dimensional hydrodynamical simulations of hot accretion flows is that the flow is convectively unstable, because of its inward increase of entropy.
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21 01 10 - 12:12 |
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Jets on all scales
http://www.arxiv.org/abs/1001.3561Amir Levinson (TAU)
9 pages, HEPROII review talk
A brief overview of jets and their central drivers is presented, with a focus on accreting black hole systems.
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