Radiation Hydrodynamic Evolution of Primordial H II Regions

By D. Whalen, Tom Abel, M. Norman. 2003

221 citations recorded by the source corpus.

We simulate the ionization environment of z ~ 20 luminous objects formed within the framework of the current CDM (cold dark matter) cosmology and compute their UV escape fraction. These objects are likely single, very massive stars that are copious UV emitters. We present analytical estimates as well as one-dimensional radiation hydrodynamic calculations of the evolution of these first H II regions in the universe. The initially D-type ionization front (I-front) evolves to become R-type within ≲105 yr at a distance of ~1 pc. This ionization front then completely overruns the halo, accelerating an expanding shell of gas outward to velocities in excess of 30 km s-1, about 10 times the escape velocity of the confining dark matter halo. We find that the evolution of the H II region depends only weakly on the assumed stellar ionizing luminosities. Consequently, most of the gas surrounding the first stars will leave the dark halo whether or not the stars produce supernovae. If they form the first massive seed black holes, these are unlikely to accrete within a Hubble time after they formed until they are incorporated into larger dark matter halos that contain more gas. Because these I-fronts exit the halo on timescales much shorter than the stars' main-sequence lifetimes, their host halos have UV escape fractions of ≳0.95, fixing an important parameter for theoretical studies of cosmological hydrogen reionization.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/7e098044e1453c7f3872fa8ba64140db396d1ea3

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. John H. Wise
2. Volker Bromm
3. Tom Abel
4. L. Hernquist
5. S. Khochfar
6. Renyue Cen
7. A. Ferrara
8. S. Glover

Citations in the corpus

• Fluctuations in the high-redshift Lyman–Werner background: close halo pairs as the origin of supermassive black holes (2008, methodology): “6 Whalen et al. (2004) found fesc ∼ 1 for galaxies at z ∼ 20, using one-dimensional hydrodynamic calculation.”
• The First Stars: Mass Growth Under Protostellar Feedback (2011, background): “Through their emission of ionizing radiation over their lifetime, Pop III stars are responsible for the beginning of cosmic reionization (e.g. ⋆ E-mail: minerva@astro.as.utexas.edu Kitayama et al. 2004; Sokasian et al. 2004; Whalen et al. 2004; Alvarez et al. 2006; Johnson et al. 2007).”
• Resolving the Formation of Protogalaxies. II. Central Gravitational Collapse (2007, background): “Negative feedback may occur from baryonic expulsion from host halos (Whalen et al. 2004; Kitayama et al. 2004; Yoshida et al. 2007; Abel et al. 2007) and halo photoevaporation (Susa & Umemura 2006; Whalen et al. 2008).”
• THE BIRTH OF A GALAXY: PRIMORDIAL METAL ENRICHMENT AND STELLAR POPULATIONS (2010, background): “The over-pressurized H II region drives a 30 km s−1 shock that is 10 times greater than the escape velocity of the halo, leaving behind a warm (3× 104 K) and diffuse (0.5 cm−3) medium (Kitayama et al. 2004; Whalen et al. 2004; Abel et al. 2007).”
• The First Billion Years project: the impact of stellar radiation on the co-evolution of Populations II and III (2012, background): “…energy radiation that ionizes and heats the gas in and around their host dark matter (DM) haloes (e.g. Kitayama ⋆ E-mail: jlj@lanl.gov et al. 2004; Whalen et al. 2004; Alvarez et al. 2006; Abel et al. 2007; Johnson et al. 2007), and also destroys H2 and HD molecules in the primordial gas over…”
• ACCRETION ONTO THE FIRST STELLAR-MASS BLACK HOLES (2007, background): “They influenced subsequent structure formation through their UV radiation heating the surrounding gas and initiating reionization (Whalen et al. 2004; Kitayama et al. 2004; Alvarez et al. 2006; Johnson & Bromm 2007; Abel et al. 2007; Yoshida et al. 2007; Wise & Abel 2007, 2008).”
• Self-regulated reionization (2006, background): “A single star was then sufficient to expel the gas from the minihalo that made it, by photoionizing the gas (Whalen et al. 2004; Kitayama etl.”
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionization (2016, background): “It can be seen that only massive Pop III stars with MPopIII >∼ 100 M are able to provide LyC photons to the IGM (Whalen et al. 2004), while almost all of the ionising radiation from MNRAS 000, 000–000 (0000) Pop III stars with MPopIII <∼ 70 M is absorbed inside the virial radius.”
• Suppression of H2 Cooling in the Ultraviolet Background (2007, background): “— Baryonic expulsion from host halos (Whalen et al. 2004; Kitayama et al. 2004; Yoshida et al. 2007; Abel et al. 2007), photoevaporation (Susa & Umemura 2006), entropy floors (Oh & Haiman 2003).”
• The global 21-centimeter background from high redshifts (2006, background): “The long-dashed curves take f esc = 1 (which may be appropriate for the first stars, Whalen et al. 2004, although it is likely an overestimate in larger galaxies).”
• Resolving the Formation of Protogalaxies. III. Feedback from the First Stars (2007, background): “One-dimensional calculations (Whalen et al. 2004; Kitayama et al. 2004; Kitayama & Yoshida 2005) and recent three-dimensional radiation hydrodynamical simulations (Yoshida et al. 2007; Abel et al. 2007) have investigated how the Pop III stellar feedback affects its host halo and nearby cosmic…”
• Resolving the Formation of Protogalaxies. I. Virialization (2007, methodology): “…additional physics, such as H2 and HD cooling physics (Saslaw & Zipoy 1967; Palla et al. 1983; Flower et al. 2000), primordial stellar feedback (Whalen et al. 2004; Kitayama et al. 2004; Alvarez et al. 2006; Yoshida et al. 2006a; Abel et al. 2007), metal enrichment from primordial stars (Heger…”