The legacy of Spitzer and Herschel, the advent of ALMA

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Table of contents

List of Figures
List of Tables
1 Introduction
1.1 Preamble and definitions
1.2 The central role of massive stars
1.3 A first step : Low-mass star formation
1.3.1 Theory
1.3.2 Empirical evolutionary sequence
1.4 Towards higher masses: when radiation comes into play
1.5 Current models of massive star formation
1.6 The legacy of Spitzer and Herschel, the advent of ALMA
1.7 Recent numerical advances
1.8 This work
1.9 Essentials
1.9.1 Stability of a cloud: order of magnitude consideration
1.9.2 Pertubative analysis
1.9.3 Virial theorem applied to a collapsing cloud
1.9.4 Radiative or magnetic outflows?
2 Radiative Transfer
2.1 Fundamental quantities and equation of transfer
2.1.1 Definitions
2.1.2 The radiative transfer equation
2.1.3 Absorption, emission, scattering
2.2 Moment models
2.2.1 Gray radiative transfer
2.2.2 Flux-limited diffusion
2.2.3 M1 model
2.2.4 Hybrid radiative transfer
2.3 Radiation Hydrodynamics equations
2.3.1 Why Radiation Hydrodynamics in star formation?
2.3.2 Equations in the non-relativistic regime
3 RAMSES and the Hybrid Radiative Transfer method
3.1 The RAMSES code
3.1.1 The AMR structure
3.1.2 Solving the Euler equations on a Cartesian grid
3.1.3 Magneto-hydrodynamics with ambipolar diffusion
3.2 The Flux-Limited Diffusion implementation
3.2.1 The explicit step for the conservative part
3.2.2 The implicit step for gas-radiation coupling and diffusion
3.3 RAMSES-RT
3.3.1 Radiation transport
3.3.2 Radiation injection
3.3.3 Gas-radiation coupling
3.4 A hybrid implementation for stellar irradiation
3.5 Pure radiative transfer tests
3.5.1 Optically-thin and moderately optically-thick cases
3.5.2 Very optically-thick case
3.5.3 Temperature structure with isotropic scattering
3.5.4 Performance test
3.5.5 Perspectives
4 Massive Star Formation with RadiationHydrodynamics
4.1 Collapse of a massive pre-stellar core with hybrid RT and hydrodynamics
4.1.1 Included physics
4.1.2 Setup
4.1.3 Results – overview
4.1.4 Disk properties
4.1.5 Radiative cavities – outflows
4.1.6 Accretion via Rayleigh-Taylor instabilities?
4.1.7 Physical outcomes
4.1.8 Performance
4.2 Modelling disk fragmentation in numerical codes
4.2.1 Context
4.2.2 Initial conditions
4.2.3 Disk properties
4.2.4 Stellar properties
4.2.5 Run with secondary sink particles
4.2.6 Extension of the comparison study and perspectives
5 Collapse of turbulent cores with radiation-magneto-hydrodynamics
5.1 Context
5.2 Methods
5.2.1 Radiation magneto-hydrodynamical model
5.2.2 Physical setup
5.2.3 Resolution and sink particles
5.2.4 Analysis: disk and outflow identification
5.3 Temporal evolution
5.3.1 Overview
5.3.2 Alignment between the angular momentum and the magnetic field
5.3.3 Interchange instability
5.3.4 Sink mass history
5.3.5 Disk properties
5.4 Outflows
5.4.1 Origin
5.4.2 A channel for radiation?
5.4.3 Outflow velocity, mass, dynamical time, ejection rate
5.4.4 Outlow momentum rate
5.4.5 Opening angles
5.4.6 Alignment with the magnetic field
5.5 Conclusions
6 Conclusions and Perspectives
Appendices
A Basics of Virial theorem
B Core gravitational and rotational energy
C Luminosity injection in the sink particle volume
Bibliography