Impact of Lyman alpha pressure on metal-poor dwarf galaxies

Abstract

Understanding the origin of strong galactic outflows and the suppression of star formation in dwarf galaxies is a key problem in galaxy formation. Using a set of radiation-hydrodynamic simulations of an isolated dwarf galaxy embedded in a $10^{10}{M}_{\odot }$ halo, we show that the momentum transferred from resonantly scattered Lyman-$\alpha$ (Lya) photons is an important source of stellar feedback which can shape the evolution of galaxies. We find that Lya feedback suppresses star formation by a factor of two in metal-poor galaxies by regulating the dynamics of star-forming clouds before the onset of supernova explosions (SNe). This is possible because each Lya photon resonantly scatters and imparts 10-300 times greater momentum than in the single scattering limit. Consequently, the number of star clusters predicted in the simulations is reduced by a factor of $\sim 5$, compared to the model without the early feedback. More importantly, we find that galactic outflows become weaker in the presence of strong Lya radiation feedback, as star formation and associated SNe become less bursty. We also examine a model in which radiation field is arbitrarily enhanced by a factor of up to 10, and reach the same conclusion. The typical mass loading factors in our metal-poor dwarf system are estimated to be $\sim 5-10$ near the mid plane, while it is reduced to $\sim 1$ at larger radii. Finally, we find that the escape of ionizing radiation and hence the reionization history of the Universe is unlikely to be strongly affected by Lya feedback.

19 pages, 16 figures, Accepted for publication in MNRAS

References in corpus (34)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample
• Mass, Metal, and Energy Feedback in Cosmological Simulations
• The Origin of the Galaxy Mass-Metallicity Relation and Implications for Galactic Outflows
• 3D Lyman-alpha radiation transfer. I. Understanding Lyman-alpha line profile morphologies
• Momentum Injection by Supernovae in the Interstellar Medium
• Escape fraction of ionizing photons during reionization: effects due to supernova feedback and runaway OB stars
• Metallicity Effects on Dust Properties in Starbursting Galaxies
• Lyman Alpha Emitting Galaxies as a Probe of Reionization
• Before the first supernova: combined effects of HII regions and winds on molecular clouds
• The First Billion Years Project: The escape fraction of ionizing photons in the epoch of reionization
• The stellar mass-halo mass relation of isolated field dwarfs: a critical test of $\Lambda$CDM at the edge of galaxy formation
• On the interplay between star formation and feedback in galaxy formation simulations
• Bent by baryons: the low mass galaxy-halo relation
• A Superbubble Feedback Model for Galaxy Simulations
• A scheme for radiation pressure and photon diffusion with the M1 closure in RAMSES-RT
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionisation
• Dependence of Interstellar Turbulent Pressure on Supernova Rate
• Vertical structure of a supernova-driven turbulent magnetized ISM
• A simple multigrid scheme for solving the Poisson equation with arbitrary domain boundaries
• Superbubbles in the Multiphase ISM and the Loading of Galactic Winds
• MUFASA: Galaxy star formation, gas, and metal properties across cosmic time
• Magnetohydronamic Evolution of HII Regions in Molecular Clouds: Simulation Methodology, Tests, and Uniform Media
• Mutual influence of supernovae and molecular clouds
• Galaxies that Shine: radiation-hydrodynamical simulations of disk galaxies
• Simulations of magnetized multiphase galactic disk regulated by supernovae explosions
• Numerical Simulations of Turbulent, Molecular Clouds Regulated by Radiation Feedback Forces I: Star Formation Rate and Efficiency
• Feedback in Clouds II: UV Photoionisation and the first supernova in a massive cloud
• Radiation Feedback in ULIRGS: Are Photons Movers and Shakers?
• Mapping Neutral Hydrogen During Reionization with the Ly-alpha Emission from Quasar Ionization Fronts
• Galaxy Size Problem at z=3: Simulated Galaxies Are Too Small
• Lyman Alpha Driven Outflows Around Star Forming Galaxies
• Lyman-alpha radiation hydrodynamics of galactic winds before cosmic reionization

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• A census of $\rho$ Oph candidate members from Gaia DR2
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization II. The Deepest Near-Infrared Spectroscopic Observation at $z\gtrsim 7$
• A high baryon fraction in massive haloes at z~3
• Lyman-alpha radiation pressure: an analytical exploration