papers

Publications (20)

astro-ph.GA2020

Simulating Star Clusters Across Cosmic Time: II. Escape Fraction of Ionizing Photons from Molecular Clouds

Chong-Chong He, Massimo Ricotti, Sam Geen

We calculate the hydrogen and helium-ionizing radiation escaping star-forming molecular clouds, as a function of the star cluster mass and compactness, using a set of high-resoluti…

astro-ph.GA2022

Influence of protostellar jets and HII regions on the formation and evolution of stellar clusters

Antoine Verliat, Patrick Hennebelle, Marta González +2

Context. Understanding the conditions in which stars and stellar clusters form is of great importance. In particular the role that stellar feedback may have is still hampered by la…

astro-ph.GA2020

The Geometry and Dynamical Role of Stellar Wind Bubbles in Photoionised HII Regions

Sam Geen, Rebekka Bieri, Joakim Rosdahl +1

Winds from young massive stars contribute a large amount of energy to their host molecular clouds. This has consequences for the dynamics and observable structure of star-forming c…

astro-ph.GA2024

The Energy and Dynamics of Trapped Radiative Feedback with Stellar Winds

Sam Geen, Rebekka Bieri, Alex de Koter +2

In this paper, we explore the significant, non-linear impact that stellar winds have on H ii regions. We perform a parameter study using three-dimensional radiative magnetohydrodyn…

astro-ph.GA2017

Interpreting the Star Formation Efficiency of Molecular Clouds with Ionising Feedback

Sam Geen, Juan D Soler, Patrick Hennebelle

We investigate the origin of observed local star formation relations using radiative magnetohydrodynamic simulations with self-consistent star formation and ionising radiation. We…

astro-ph.GA2019

Simulating Star Clusters Across Cosmic Time: I. Initial Mass Function, Star Formation Rates and Efficiencies

Chong-Chong He, Massimo Ricotti, Sam Geen

We present radiation-magneto-hydrodynamic simulations of star formation in self-gravitating, turbulent molecular clouds, modeling the formation of individual massive stars, includi…

astro-ph.GA2019

On the Indeterministic Nature of Star Formation on the Cloud Scale

Sam Geen, Stuart K. Watson, Joakim Rosdahl +3

Molecular clouds are turbulent structures whose star formation efficiency (SFE) is strongly affected by internal stellar feedback processes. In this paper we determine how sensitiv…

astro-ph.GA2022

The SATIN project I: Turbulent multi-phase ISM in Milky Way simulations with SNe feedback from stellar clusters

Rebekka Bieri, Thorsten Naab, Sam Geen +3

We introduce the star formation and Supernova (SN) feedback model of the SATIN (Simulating AGNs Through ISM with Non-Equilibrium Effects) project to simulate the evolution of the s…

astro-ph.GA2021

Bottling the Champagne: Dynamics and Radiation Trapping of Wind-Driven Bubbles around Massive Stars

Sam Geen, Alex de Koter

In this paper we make predictions for the behaviour of wind bubbles around young massive stars using analytic theory. We do this in order to determine why there is a discrepancy be…

astro-ph.SR2023

Bringing Stellar Evolution & Feedback Together: Summary of proposals from the Lorentz Center Workshop, 2022

Sam Geen, Poojan Agrawal, Paul A. Crowther +34

Stars strongly impact their environment, and shape structures on all scales throughout the universe, in a process known as ``feedback''. Due to the complexity of both stellar evolu…

astro-ph.GA2019

When H II Regions are Complicated: Considering Perturbations from Winds, Radiation Pressure, and Other Effects

Sam Geen, Eric Pellegrini, Rebekka Bieri +1

We explore to what extent simple algebraic models can be used to describe H II regions when winds, radiation pressure, gravity and photon breakout are included. We a) develop algeb…

astro-ph.GA2018

Impact of galactic shear and stellar feedback on star formation

Cédric Colling, Patrick Hennebelle, Sam Geen +2

A numerical shearing box is used to perform three-dimensional simulations of a 1 kpc stratified cubic box of turbulent and self-gravitating interstellar medium (in a rotating frame…

astro-ph.SR2022

Trapping of HII regions in Population III star formation

Ondrej Jaura, Simon C. O. Glover, Katharina M. J. Wollenberg +3

Radiative feedback from massive Population III (Pop III) stars in the form of ionising and photodissociating photons is widely believed to play a central role in shutting off accre…

astro-ph.CO2012

Satellite Survival in Highly Resolved Milky Way Class Halos

Sam Geen, Adrianne Slyz, Julien Devriendt

Surprisingly little is known about the origin and evolution of the Milky Way's satellite galaxy companions. UV photoionisation, supernova feedback and interactions with the larger…

astro-ph.SR2022

The R136 star cluster dissected with Hubble Space Telescope/STIS. III. The most massive stars and their clumped winds

Sarah A. Brands, Alex de Koter, Joachim M. Bestenlehner +17

Context: The star cluster R136 inside the LMC hosts a rich population of massive stars, including the most massive stars known. The strong stellar winds of these very luminous star…

astro-ph.GA2015

A Detailed Study of Feedback from a Massive Star

Sam Geen, Joakim Rosdahl, Jeremy Blaizot +2

We present numerical simulations of a 15 solar mass star in a suite of idealised environments in order to quantify the amount of energy transmitted to the interstellar medium (ISM)…

astro-ph.GA2021

A systematic study of the escape of LyC and Ly photons from star-forming, magnetized turbulent clouds

Taysun Kimm, Rebekka Bieri, Sam Geen +4

Understanding the escape of Lyman continuum (LyC) and Lyman (Ly) photons from giant molecular clouds (GMCs) is crucial if we are to study the reionization of the Universe…

astro-ph.GA2016

Feedback in Clouds II: UV Photoionisation and the first supernova in a massive cloud

Sam Geen, Patrick Hennebelle, Pascal Tremblin +1

Molecular cloud structure is regulated by stellar feedback in various forms. Two of the most important feedback processes are UV photoionisation and supernovae from massive stars.…

astro-ph.GA2016

Photoionisation Feedback in a Self-Gravitating, Magnetised, Turbulent Cloud

Sam Geen, Patrick Hennebelle, Pascal Tremblin +1

We present a new set of analytic models for the expansion of HII regions powered by UV photoionisation from massive stars and compare them to a new suite of radiative magnetohydrod…

astro-ph.GA2011

How Does Feedback Affect Milky Way Satellite Formation?

Sam Geen, Adrianne Slyz, Julien Devriendt

We use sub-parsec resolution hydrodynamic resimulations of a Milky Way (MW) like galaxy at high redshift to investigate the formation of the MW satellite galaxies. More specificall…