Adam Ginsburg Merge branch 'master' of github.com:keflavich/thesis Conflicts: thesis.pdf  about 11 years ago

Commit id: 1308ab720e1d5fdee95e671ae1a1c01fe1f7c1eb

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$$\dot{M}_{BH} = \frac{4 \pi \rho G^2 M^2}{c_s^3} $$  For a low-mass star in a low-density medium and a high-mass star in a high-density medium,  the values are  $$\dot{M}_{BH} = 1.6\times10^{-7} \left(\frac{M}{M_\odot}\right)^2 \left(\frac{n}{10^4 \text{cm}^{-3}}\right) \mathrm{cm}^{-3}}\right)  \left(\frac{c_s}{1 \text{km \mathrm{km  s}^{-1}}\right)^{-3} \msun \peryr$$ $$\dot{M}_{BH} = 1.6\times10^{-4} \left(\frac{M}{10 M_\odot}\right)^2 \left(\frac{n}{10^5 \text{cm}^{-3}}\right) \mathrm{cm}^{-3}}\right)  \left(\frac{c_s}{1 \text{km \mathrm{km  s}^{-1}}\right)^{-3} \msun \peryr$$ The timescale for a 10\msun star to double its mass in a $n\sim10^5\percc$  medium is $\sim50$ kyr, but drops to only $5$ kyr for density  $n\sim10^6\percc$.  

determined entirely by turbulence. In this description, the highest  overdensities in the turbulent medium become gravitationally unstable and  separate from the turbulent flow as they collapse into proto-stellar cores.  This idea has been a hot topic in the past few years, butI will not address  it may be an overly  simplistic view.  Turbulence is appealing to theorists as it is a difficult problem to address  directly with observations, but it may have great predictive power. If turbulence  is the dominant governing process of the ISM, then it is possible to derive a  reasonably robust star-formation theory based on the excursion set theory  successfully applied to cosmological structure formation  \citep{Hopkins2012b,Hennebelle2011a,Hopkins2012d}.   However, in reality, turbulence is just one of many processes governing the ISM  and star formation. Stellar feedback, in the form of radiation, winds,  supernovae, and outflows imposes a preferred driving scale on any individual  region, and  in many cases these processes will happen faster than turbulent  processes. The notion of \emph{initial conditions} for star formation,  while theoretically appealing, may prove too strong an oversimplification  when searching for a complete theory of star formation.  Throughout  this thesis. thesis, I consider and measure the drivers, effects and  properties of turbulence on a few different scales.  In the W5 and IRAS 05358 regions (Chapter \ref{ch:w5} and  \citet{Ginsburg2009}), I examined outflows as potential drivers of turbulence.         

  @article{Hennebelle2011a,  Author = {{Hennebelle}, P. and {Chabrier}, G.},  Journal = {\apjl},  Month = dec,  Pages = {L29},  Title = {{Analytical Star Formation Rate from Gravoturbulent Fragmentation}},  Volume = 743,  Year = 2011}  @article{Hopkins2012d,  Author = {{Hopkins}, P.~F.},  Journal = {\mnras},  Month = jul,  Pages = {2016-2036},  Title = {{An excursion-set model for the structure of giant molecular clouds and the interstellar medium}},  Volume = 423,  Year = 2012}  @article{Whitmore2009a,  Author = {{Whitmore}, B.~C.},  Journal = {\apss}, 

pages = {57--115}  },  @article{Aguirre2010,  title={The Bolocam Galactic Plane Survey I: Methods},  author = {James Aguirre and Adam Ginsburg and BGPS Team},  journal = {In Prep},  year={2010}  }  @inproceedings{bretherton:unbiased:2002,  title = {An Unbiased Survey for Outflows in the W3 and W5 Star-Formation Regions},        Binary files /dev/null and b/thesis.pdf differ