Apparent Brightness » Star Formation http://apparentbrightness.net astronomy and stuff Mon, 03 Dec 2007 16:07:54 +0000 http://wordpress.org/?v=2.6.1 en Monolithic or hierarchical star formation? A new statistical analysis http://apparentbrightness.net/2007/12/03/monolithic-or-hierarchical-star-formation-a-new-statistical-analysis/ http://apparentbrightness.net/2007/12/03/monolithic-or-hierarchical-star-formation-a-new-statistical-analysis/#comments Mon, 03 Dec 2007 15:35:59 +0000 Thomas Marquart http://apparentbrightness.net/2007/12/03/monolithic-or-hierarchical-star-formation-a-new-statistical-analysis/
  • Kampakoglou et al.
  • http://arxiv.org/abs/0709.1104
  • Statistical model to predict/fit the star formation history of the universe. Hierarchical formation through merging seems to be favoured but not enough to exclude the monolithic scenario. Outflow models and dust are critical.

    • My impression is that the two priciple modes of galaxy formation seem to be subject to fashion among astronomers. While monolithic has been favoured in the early days of extragalacitc astronomy, the hierarchical formation was preferred until lately when it was realised that the former probably also plays a role.

    ]]>     http://apparentbrightness.net/2007/12/03/monolithic-or-hierarchical-star-formation-a-new-statistical-analysis/feed/     Star-formation in the HI bridge between M81 and M82 http://apparentbrightness.net/2007/11/20/star-formation-in-the-hi-bridge-between-m81-and-m82/ http://apparentbrightness.net/2007/11/20/star-formation-in-the-hi-bridge-between-m81-and-m82/#comments Tue, 20 Nov 2007 14:13:50 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/20/star-formation-in-the-hi-bridge-between-m81-and-m82/
  • de Mello et al.
  • http://arxiv.org/abs/0711.2685
  • They found both old and young stars in the region between the two galaxies and conclude that the former were flung out of either of the two while the latter have formed in the tidal tail.
  • Overall, there seems to be quite little going on there compared to other tidal tails (e.g. of mergers) where active star formation is often seen.
    • ]]>     http://apparentbrightness.net/2007/11/20/star-formation-in-the-hi-bridge-between-m81-and-m82/feed/     The UV properties of E+A galaxies: constraints on feedback-driven quenching of star formation http://apparentbrightness.net/2007/11/05/the-uv-properties-of-ea-galaxies-constraints-on-feedback-driven-quenching-of-star-formation/ http://apparentbrightness.net/2007/11/05/the-uv-properties-of-ea-galaxies-constraints-on-feedback-driven-quenching-of-star-formation/#comments Mon, 05 Nov 2007 07:04:25 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/05/the-uv-properties-of-ea-galaxies-constraints-on-feedback-driven-quenching-of-star-formation/
  • Kaviraj et al.
  • http://arxiv.org/abs/0707.3570
  • postburst galaxies and quenching of star-formation
  • connection to ULIRGs
    • ]]>     http://apparentbrightness.net/2007/11/05/the-uv-properties-of-ea-galaxies-constraints-on-feedback-driven-quenching-of-star-formation/feed/     Star-Formation Rates of Local Blue Compact Dwarf Galaxies I: 1.4 GHz and 60 um luminosities http://apparentbrightness.net/2007/11/05/star-formation-rates-of-local-blue-compact-dwarf-galaxies-i-14-ghz-and-60-um-luminosities/ http://apparentbrightness.net/2007/11/05/star-formation-rates-of-local-blue-compact-dwarf-galaxies-i-14-ghz-and-60-um-luminosities/#comments Mon, 05 Nov 2007 06:57:47 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/05/star-formation-rates-of-local-blue-compact-dwarf-galaxies-i-14-ghz-and-60-um-luminosities/
  • Hopkins et al.
  • http://arxiv.org/abs/astro-ph/0204528
  • star-formation rates of 50 well known, local Blue Compact Dwarf (BCD) galaxies based on their 1.4 GHz and 60 $\mu$m luminosities
  • Mk600, SBS0335-052, IZw18, UM461, UM462, Mk930
    • ]]>     http://apparentbrightness.net/2007/11/05/star-formation-rates-of-local-blue-compact-dwarf-galaxies-i-14-ghz-and-60-um-luminosities/feed/     The Initial Cluster Mass Function of Super Star Clusters in Irregular and Spiral Galaxies http://apparentbrightness.net/2007/11/02/the-initial-cluster-mass-function-of-super-star-clusters-in-irregular-and-spiral-galaxies/ http://apparentbrightness.net/2007/11/02/the-initial-cluster-mass-function-of-super-star-clusters-in-irregular-and-spiral-galaxies/#comments Fri, 02 Nov 2007 09:30:35 +0000 Thomas Marquart http://apparentbrightness.net/2007/11/02/the-initial-cluster-mass-function-of-super-star-clusters-in-irregular-and-spiral-galaxies/
  • Dowell et al.
  • http://arxiv.org/abs/astro-ph/0611586
  • SSCs in nearby spirals and irregulars from SDSS
  • SDSS colors plus spectral evolutionary modelling to determine cluster ages and mass.
  • They find a steeper slope for the mass function (at high masses) in irregulars as compared to spirals.
  • I wonder how reliable the masses are from this method. It’s a tricky business and dynamical cluster masses would be nicer.
    • ]]>     http://apparentbrightness.net/2007/11/02/the-initial-cluster-mass-function-of-super-star-clusters-in-irregular-and-spiral-galaxies/feed/     The evolution of very massive stars http://apparentbrightness.net/2007/10/31/the-evolution-of-very-massive-stars/ http://apparentbrightness.net/2007/10/31/the-evolution-of-very-massive-stars/#comments Wed, 31 Oct 2007 14:40:14 +0000 Thomas Marquart http://apparentbrightness.net/2007/10/31/the-evolution-of-very-massive-stars/
  • Belkus et al.
  • http://arxiv.org/abs/astro-ph/0701334
  • dense clusters
  • supermassive stars
    • ]]>     http://apparentbrightness.net/2007/10/31/the-evolution-of-very-massive-stars/feed/     A Population of Massive and Evolved Galaxies at z >5 http://apparentbrightness.net/2007/10/31/a-population-of-massive-and-evolved-galaxies-at-z-5/ http://apparentbrightness.net/2007/10/31/a-population-of-massive-and-evolved-galaxies-at-z-5/#comments Wed, 31 Oct 2007 14:00:19 +0000 Thomas Marquart http://apparentbrightness.net/2007/10/31/a-population-of-massive-and-evolved-galaxies-at-z-5/ 9 ]]>
  • Wiklind et al.
  • http://arxiv.org/abs/0710.0406
  • early red and dead galaxies that formed their stars at z >9
    • ]]>     http://apparentbrightness.net/2007/10/31/a-population-of-massive-and-evolved-galaxies-at-z-5/feed/