Newly Minted PhD: Qi Ge

Today, Qi Ge successfully defended his thesis, “On the Effect of Lyman Alpha Trapping during the Initial Collapse of Massive Black Hole Seeds”.  You can find most of his results in this paper. He’ll be starting as a software research scientist at a Chinese startup that specializes in self-driving cars.  In particular, he’ll be working on machine learning techniques there. Congratulations, Qi!

New Paper: Supermassive Star Formation in a Cosmological Context

Last week we submitted a paper (arXiv) on simulating the direct gaseous collapse into a massive black hole, led by Osaka postdoc Kazem Ardaneh. This work is a companion to an earlier paper led by Yang Luo, a postdoc at the University of Kentucky and Osaka.  It provides more realistic conditions (mass distribution, turbulence & rotational properties) to study this catastrophic collapse.

Here we used the same radiation hydrodynamics machinery to follow a cosmological halo collapsing to stellar densities. We study the complex interplay between the strong inflowing gas and the radiation coming from the photosphere of the nascent star. The luminosity of the central object strongly fluctuates around the Eddington luminosity (10^38 to 10^39 erg/s) and grows to 10 solar masses only within 35 years. This object is thought to be the seed of a supermassive star on the order of 1,000 to 100,000 solar masses that continues to grow from the strong inflows, even in the presence of radiative feedback.

07 Mar 2018

  • (abs, pdf) Wheeler et al., The radial acceleration relation is a natural consequence of the baryonic Tully-Fisher relation
  • (abs, pdf) Obied et al., Inflationary vs. Reionization Features from Planck 2015 Data
  • (abs, pdf) Matsuoka et al., Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). IV. Discovery of 41 Quasars and Luminous Galaxies at 5.7 < z < 6.9
  • (abs, pdf) Jung et al., Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization I. Constraining the Ly$\alpha$ Equivalent Width Distribution at 6.0 < $z$ < 7.0
  • (abs, pdf) Patel et al., Estimating the Mass of the Milky Way Using the Ensemble of Classical Satellite Galaxies
  • (abs, pdf) Hou et al., A comparison between semi-analytical gas cooling models and hydrodynamical simulations

06 Mar 2018

  • (abs, pdf) Dunn et al., Sowing black hole seeds: Direct collapse black hole formation with realistic Lyman-Werner radiation in cosmological simulations
  • (abs, pdf) Deparis et al., The impact of the reduced speed of light approximation on ionization front velocities in cosmological simulations of the epoch of reionization
  • (abs, pdf) Schneider & Robertson, Introducing CGOLS: The Cholla Galactic OutfLow Simulation Suite
  • (abs, pdf) Jaffa et al., J plots: a new method for characterizing structures in the interstellar medium
  • (abs, pdf) Chiti et al., Chemical Abundances of new member stars in the Tucana II dwarf galaxy
  • (abs, pdf) Ewall-Wice et al., Modeling the Radio Background from the First Black Holes at Cosmic Dawn: Implications for the 21 cm Absorption Amplitude