Jul 10, 2013 ... Mind The Gap, Cambrige -. 08/07/2013. Modelling radiative feedback in star
forming regions. Thomas Haworth. Tim Harries, David Acreman.
Modelling radiative feedback in star forming regions
Thomas Haworth Tim Harries, David Acreman Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Bonnell + (2013), 430, 1790
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Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Bonnell + (2013), 430, 1790
IC1848 Spitzer Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
TORUS is a state of the art radiation transport code with a hydrodynamics module bolted on.
• Adaptive mesh refinement (AMR) • Monte Carlo radiative transfer • Dust continuum • Photoionization • Atomic lines • Molecular lines • Hydrodynamics • TVD scheme with superbee flux limiter
• Self-gravity • Multigrid Poisson solver • Dirichlet boundary conditions • Lagrangian sink particles • Parallelization • Domain decomposed • MPI+openmp
Have all of the features of a dedicated radiative transfer code available for RHD calculations Haworth & Harries, 2012, MNRAS, 420, 562 Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Harries 2000
Approximations 1. Hydrogen only
1. Helium and metals
2. Monochromatic radiation
2. Polychromatic
3. The on the spot approximation
3. Diffuse field
1. Simplified thermal balance
1. Match heating/cooling rates
1. Photoionization equilibrium
1. Time dependent photoinization
Resolution?
Limited to 2D models to explore this at present Mind The Gap, Cambrige 08/07/2013
Wednesday, 10 July 13
Approximations 1. Hydrogen only
1. Helium and metals
2. Monochromatic radiation
2. Polychromatic
3. The on the spot approximation
3. Diffuse field
1. Simplified thermal balance
1. Match heating/cooling rates
1. Photoionization equilibrium
1. Time dependent photoinization
Resolution?
Limited to 2D models to explore this at present Mind The Gap, Cambrige 08/07/2013
Wednesday, 10 July 13
Models
Osterbrock – astrophysics of gaseous nebulae and AGN
Fits to Verner & Ferland 1996, ApJ, 106, 467 Mind The Gap, Cambrige 08/07/2013
Wednesday, 10 July 13
Models
Osterbrock – astrophysics of gaseous nebulae and AGN
Fits to Verner & Ferland 1996, ApJ, 106, 467 Mind The Gap, Cambrige 08/07/2013
Wednesday, 10 July 13
Initial setup 2D slab No gravity, free fall time 3Myr, tend=200kyr (not important from 3D model test) Star at centre of grid
4 Bonnor-Ebert spheres Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Pictures
Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Ionized/neutral mass
Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
The density distribution
Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Summarised differences
Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Conclusions I get no resolution convergence The disruption to the density distribution seems to converge with diffuse fields, helium and metals, not too sensitive to the thermal balance. High sensitivity to the recombination coefficient used/diffuse field treatment Difficult to make quantitative conclusions using RHD models This is just one code! Keep an eye out for StarBench-2 Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
Plug/Questions?
http://www.astro.ex.ac.uk/people/th2/torus_html/homepage.html Haworth & Harries, 2012, MNRAS, 420, 562 Haworth et al., 2012, MNRAS, 426, 203 Haworth et al., 2013, MNRAS, 431, 3470
Haworth et al., 2013, in prep
Mind The Gap, Cambrige 08/07/2013 Wednesday, 10 July 13
