http://apparentbrightness.net astronomy and stuff Mon, 03 Dec 2007 16:07:54 +0000 http://wordpress.org/?v=2.6.1 en http://apparentbrightness.net/2007/12/03/resolving-gas-dynamics-in-the-circumnuclear-region-of-a-disk-galaxy-in-a-cosmological-simulation/ http://apparentbrightness.net/2007/12/03/resolving-gas-dynamics-in-the-circumnuclear-region-of-a-disk-galaxy-in-a-cosmological-simulation/#comments Mon, 03 Dec 2007 16:07:54 +0000 Thomas Marquart http://apparentbrightness.net/2007/12/03/resolving-gas-dynamics-in-the-circumnuclear-region-of-a-disk-galaxy-in-a-cosmological-simulation/

Levine et al.

http://arxiv.org/abs/0711.3478

Simulation with high dynamic range (1E7) down to 0.1pc, i.e. to the accretion disk of a SMBH.

Global instabilities make things quasi-stable locally due to turbulence.

An exponential density profile for the gas in a disk arises naturally due to this.

]]> http://apparentbrightness.net/2007/12/03/resolving-gas-dynamics-in-the-circumnuclear-region-of-a-disk-galaxy-in-a-cosmological-simulation/feed/ http://apparentbrightness.net/2007/11/12/the-role-of-minor-mergers-in-the-recent-star-formation-history-of-early-type-galaxies/ http://apparentbrightness.net/2007/11/12/the-role-of-minor-mergers-in-the-recent-star-formation-history-of-early-type-galaxies/#comments Mon, 12 Nov 2007 12:14:02 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/12/the-role-of-minor-mergers-in-the-recent-star-formation-history-of-early-type-galaxies/

Kaviraj et al.

http://arxiv.org/abs/0711.1493

Simulations on how minor mergers can explain the variation in UV-fluxes of ellipticals.

They say they cannot “rule out” gas accretion, but I wonder where the dividing line goes between a gas-rich dwarf being eaten and infall of gas.

]]> http://apparentbrightness.net/2007/11/12/the-role-of-minor-mergers-in-the-recent-star-formation-history-of-early-type-galaxies/feed/ http://apparentbrightness.net/2007/11/07/black-hole-growth-in-hierarchical-galaxy-formation/ http://apparentbrightness.net/2007/11/07/black-hole-growth-in-hierarchical-galaxy-formation/#comments Wed, 07 Nov 2007 09:58:01 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/07/black-hole-growth-in-hierarchical-galaxy-formation/

Malbon et al.

http://arxiv.org/abs/astro-ph/0607424

Black Hole – bulge mass relation

They find that the direct accretion of cold gas during starbursts is an important growth mechanism for lower mass black holes and at high redshift. On the other hand, the re-assembly of pre-existing black hole mass into larger units via merging dominates the growth of more massive black holes at low redshift.

As redshift decreases, progressively less massive black holes have the highest fractional growth rates, in line with recent claims of “downsizing” in quasar activity.

]]> http://apparentbrightness.net/2007/11/07/black-hole-growth-in-hierarchical-galaxy-formation/feed/ http://apparentbrightness.net/2007/10/31/2-dimensional-kinematics-of-simulated-disc-merger-remnants/ http://apparentbrightness.net/2007/10/31/2-dimensional-kinematics-of-simulated-disc-merger-remnants/#comments Wed, 31 Oct 2007 14:43:27 +0000 Thomas Marquart http://apparentbrightness.net/2007/10/31/2-dimensional-kinematics-of-simulated-disc-merger-remnants/

Jesseit et al.

http://arxiv.org/abs/astro-ph/0606144

“real” simulations are the way to go for understanding the complex velocity fields of our BCGs.

]]> http://apparentbrightness.net/2007/10/31/2-dimensional-kinematics-of-simulated-disc-merger-remnants/feed/ http://apparentbrightness.net/2007/10/31/scaling-relations-of-dwarf-galaxies-without-supernova-driven-winds/ http://apparentbrightness.net/2007/10/31/scaling-relations-of-dwarf-galaxies-without-supernova-driven-winds/#comments Wed, 31 Oct 2007 13:18:27 +0000 Thomas Marquart http://apparentbrightness.net/2007/10/31/scaling-relations-of-dwarf-galaxies-without-supernova-driven-winds/

Tassis et al.

http://arxiv.org/abs/astro-ph/0609763

Dwarf galaxies: correlations between their global stellar and dynamical properties, such as circular velocity, mass-to-light ratio, stellar mass, surface brightness, and metallicity.

low and high z

simulation work

SN winds vs. ineficient SF

useful to compare to where our data fall on these correlations

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