The First Stars
- Jarrett L. Johnson, T. Greif, V. Bromm
- PhysicsProceedings of the International Astronomical…
- 3 November 2003
Abstract The formation of the first generations of stars at redshifts z ≥ 15 − 20 signaled the transition from the simple initial state of the universe to one of ever increasing complexity. We here…
Mass fall-back and accretion in the central engine of gamma-ray bursts
- Pawan Kumar, R. Narayan, Jarrett L. Johnson
- Physics
- 2 July 2008
We calculate the rate of in-fall of stellar matter on an accretion disc during the collapse of a rapidly rotating massive star and estimate the luminosity of the relativistic jet that results from…
Ubiquitous seeding of supermassive black holes by direct collapse
- B. Agarwal, S. Khochfar, Jarrett L. Johnson, E. Neistein, C. D. Vecchia, M. Livio
- Physics
- 29 May 2012
We study for the first time the environment of massive black hole (BH) seeds (∼10 4−5 M� ) formed via the direct collapse of pristine gas clouds in massive haloes (≥10 7 M� )a tz > 6. Our model is…
Probing the formation of the first low‐mass stars with stellar archaeology
- A. Frebel, Jarrett L. Johnson, V. Bromm
- Physics
- 12 January 2007
ABSTRACT We investigate the conditions under which the first low-mass stars formed in theUniverse by confronting theoretical predictions governing the transition from massivePopulationIII to low-mass…
The First Billion Years project: the impact of stellar radiation on the co-evolution of Populations II and III
- Jarrett L. Johnson, C. D. Vecchia, S. Khochfar
- Physics
- 25 June 2012
With the first metal enrichment by Population (Pop) III supernovae (SNe), the formation of the first metal-enriched, Pop II stars becomes possible. In turn, Pop III star formation and early metal…
Properties of Gamma-Ray Burst Progenitor Stars
- Pawan Kumar, R. Narayan, Jarrett L. Johnson
- PhysicsScience
- 2 July 2008
These basic properties of stars that produce spectacular gamma-ray bursts at the end of their lives are determined and it is assumed that accretion of the outer portion of the stellar core by a central black hole fuels the prompt emission and that fall-back and accretions later produce the plateau in the x-ray light curve seen in some bursts.
THE FIRST PLANETS: THE CRITICAL METALLICITY FOR PLANET FORMATION
- Jarrett L. Johnson, Hui Li
- Physics, Geology
- 21 March 2012
A rapidly growing body of observational results suggests that planet formation takes place preferentially at high metallicity. In the core accretion model of planet formation this is expected because…
The cooling of shock-compressed primordial gas
- Jarrett L. Johnson, V. Bromm
- Physics
- 14 May 2005
We find that at redshifts z? 10, HD line cooling allows strongly shocked primordial gas to cool to the temperature of the cosmic microwave background (CMB). This temperature is the minimum value…
The First Supernova Explosions: Energetics, Feedback, and Chemical Enrichment
- T. Greif, Jarrett L. Johnson, V. Bromm, R. Klessen
- Physics
- 21 May 2007
We perform three-dimensional smoothed particle hydrodynamics simulations in a realistic cosmological setting to investigate the expansion, feedback, and chemical enrichment properties of a 200 M☉…
Detecting direct collapse black holes: making the case for CR7
- B. Agarwal, Jarrett L. Johnson, S. Khochfar
- Physics
- 6 October 2015
We propose that one of the sources in the recently detected system CR7 by Sobral et al. through spectrophotometric measurements at z=6.6 harbours a direct collapse black hole (DCBH). We argue that ...
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