01 Feb 2018

  • (abs, pdf) Hopkins & Squire, Ubiquitous Instabilities of Dust Moving in Magnetized Gas
  • (abs, pdf) Lovell et al., The fraction of dark matter within galaxies from the IllustrisTNG simulations
  • (abs, pdf) Conroy et al., Metal-rich, Metal-poor: Updated Stellar Population Models for Old Stellar Systems
  • (abs, pdf) Ceverino et al., FirstLight II: Star formation rates of primeval galaxies from z=5-15
  • (abs, pdf) Abe & Yajima, Suppression of globular cluster formation in metal-poor gas clouds by Lyman-alpha radiation feedback
  • (abs, pdf) Regier et al., Cataloging the Visible Universe through Bayesian Inference at Petascale

31 Jan 2018

  • (abs, pdf) Sameie et al., The impact of baryonic disks on the shapes and profiles of self-interacting dark matter halos
  • (abs, pdf) Alabi et al., Origins of ultra-diffuse galaxies in the Coma cluster – I. Constraints from velocity phase-space
  • (abs, pdf) Ferre-Mateu et al., Origins of ultra-diffuse galaxies in the Coma cluster II. Constraints from their stellar populations
  • (abs, pdf) Martin et al., Secular black-hole growth: Normal black holes in bulge-less galaxies: the largely quiescent, merger-free growth of black holes over cosmic time
  • (abs, pdf) Eide et al., The Epoch of IGM heating by early sources of X-rays

New paper: Connection between early and local galaxies

Earlier this month, our paper (arXiv) on the chemical enrichment of the first galaxies and their connection to local ultra-faint dwarf galaxies was accepted to MNRAS. This paper was led by JHU postdoctoral researcher Lauren Corlies. We compared the average metallicities of both simulated and actual galaxies to determine how and when they were enriched, in particular if Population III (metal-free) stars imprinted on them. We also explored an analytical model of metal enrichment (i.e. blastwave evolution) that matched the simulation data to a reasonable degree. We found that the simulation produced metallicity distributions in single galaxies that are narrower than the data, and future work is needed to address this inconsistency in simulations of low-mass galaxies.

New paper: Supermassive star formation

Last month we submitted a paper (arXiv) on the direct collapse of a gaseous cloud into the beginnings of a supermassive star that will then further collapse into massive black hole around 10,000 to 100,000 solar masses.  This paper was led by postdoctoral research Yang Luo at Osaka University and University of Kentucky.  We used the simulation code Enzo to perform this work.  The unique and groundbreaking aspect of this study was that we used radiation transport to understand how radiation slowed any cooling of the gas and thus collapse.  This can change the collapse dynamics and could have impacts on the final properties of the star. We followed the collapse all the way down to the protostellar accretion with resolution

29 Jan 2018

  • (abs, pdf) Dickinson et al., Galaxy Zoo: Morphological classification of galaxy images from the Illustris simulation
  • (abs, pdf) Luo et al., Direct Collapse to Supermassive Black Hole Seeds with Radiative Transfer: Isolated Halos
  • (abs, pdf) Corlies et al., Exploring Simulated Early Star Formation in the Context of the Ultrafaint Dwarf Galaxies
  • (abs, pdf) Barnes et al., Galaxy Formation Efficiency and the Multiverse Explanation of the Cosmological Constant with EAGLE Simulations
  • (abs, pdf) De Clercq et al., A better communicator is always a better scientist, or the reason why every PhD student should engage in science outreach

26 Jan 2018

  • (abs, pdf) Nori & Baldi, AX-GADGET: a new code for cosmological simulations of Fuzzy Dark Matter and Axion models
  • (abs, pdf) Bettinelli et al., The star formation history of the Sextans dwarf spheroidal galaxy: a true fossil of the pre-reionization era
  • (abs, pdf) Valiante et al., Chasing the observational signatures of seed black holes at z > 7: candidate observability
  • (abs, pdf) Oishi et al., Perspectives on Reproducibility and Sustainability of Open-Source Scientific Software from Seven Years of the Dedalus Project

25 Jan 2018

  • (abs, pdf) Bernhard et al., Evidence for a mass-dependent AGN Eddington ratio distribution via the flat relationship between SFR and AGN luminosity
  • (abs, pdf) Sakari et al., The r-Process Pattern of a Bright, Highly r-Process-Enhanced, Metal-Poor Halo Star at [Fe/H] ~ -2
  • (abs, pdf) Ishigaki et al., The Initial mass function of the first stars inferred from extremely metal-poor stars
  • (abs, pdf) Sipilä & Caselli, Hydrodynamics with gas-grain chemistry and radiative transfer: comparing dynamical and static models
  • (abs, pdf) Heuritsch, Insights into the effects of indicators on knowledge production in Astronomy

New Paper: Early massive black hole growth

Today we submitted a paper (arXiv) that follows the growth of a massive black hole seed in the early universe. We found that supernova explosions heat and stir up the gas inside the gas, preventing the central black hole to accrete and grow rapidly. Stars form at rates 10,000 to 100,000 times faster than the black hole grows. The main galaxy has a stellar mass of 1 billion solar masses, which totally outshines the central black hole. This could explain why there is a lack of faint AGN at high-redshift where these more “normal” massive black holes aren’t accreting very rapidly and cannot be detected with current telescopes.

24 Jan 2018

  • (abs, pdf) Elias et al., Stellar Halos in Illustris- Probing the Histories of Milky Way-Mass Galaxies
  • (abs, pdf) Latif et al., Early growth of high redshift black holes
  • (abs, pdf) Schweizer et al., The Second Nucleus of NGC 7727: Direct Evidence for the Formation and Evolution of an Ultracompact Dwarf Galaxy
  • (abs, pdf) Rosdahl et al., The SPHINX Cosmological Simulations of the First Billion Years: the Impact of Binary Stars on Reionization