Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2010-12-03
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
11 pages, 10 Figures, Accepted for publication in MNRAS
Scientific paper
We compare the three-dimensional gas temperature distributions obtained by a dedicated radiative transfer and photoionisation code, MOCASSIN, against those obtained by the recently-developed Smooth Particle Hydrodynamics (SPH) plus ionisation code iVINE for snapshots of an hydrodynamical simulation of a turbulent interstellar medium (ISM) irradiated by a nearby O star. Our tests demonstrate that the global ionisation properties of the region are correctly reproduced by iVINE, hence validating further application of this code to the study of feedback in star forming regions. However we highlight potentially important discrepancies in the detailed temperature distribution. In particular we show that in the case of highly inhomogenous density distributions the commonly employed on-the-spot (OTS) approximation yields unrealistically sharp shadow regions which can affect the dynamical evolution of the system. We implement a simple strategy to include the effects of the diffuse field in future calculations, which makes use of physically motivated temperature calibrations of the diffuse-field dominated regions and can be readily applied to similar codes. We find that while the global qualitative behaviour of the system is captured by simulations with the OTS approximation, the inclusion of the diffuse field in iVINE (called DiVINE) results in a stronger confinement of the cold gas, leading to denser and less coherent structures. This in turn leads to earlier triggering of star formation. We confirm that turbulence is being driven in simulations that include the diffuse field, but the efficiency is slightly lower than in simulations that use the OTS approximation.
Ercolano Barbara
Gritschneder Matthias
No associations
LandOfFree
Ionisation feedback in star formation simulations: The role of diffuse fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Ionisation feedback in star formation simulations: The role of diffuse fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ionisation feedback in star formation simulations: The role of diffuse fields will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-515042