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Title: The mass spectrum of the first stars

Abstract

We perform cosmological hydrodynamics simulations with non-equilibrium primordial chemistry to obtain 59 minihalos that host first stars. The obtained minihalos are used as the initial conditions of local three-dimensional radiation hydrodynamics simulations to investigate the formation of the first stars. We find that two-thirds of the minihalos host multiple stars, while the other third has single stars. The mass of the stars found in our simulations are in the range of 1 M {sub ☉} ≲ M ≲ 300 M {sub ☉}, peaking at several× 10 M {sub ☉}. Most of the very massive stars of ≳ 140 M {sub ☉} are born as single stars, although not all of the single stars are very massive. We also find a few stars of ≲ 1 M {sub ☉} that are kicked by the gravitational three body interactions to the position distant from the center of mass. The frequency that a star forming minihalo contains a binary system is ∼50%. We also investigate the abundance pattern of the stellar remnants by summing up the contributions from the first stars in the simulations. Consequently, the pattern is compatible with that of the low metallicity damped Lyα systems or the extremely metal-poor (EMP)more » stars, if the mass spectrum obtained in our experiment is shifted to the low mass side by 0.2 dex. If we consider the case that an EMP star is born in the remnant of the individual minihalo without mixing with others, the chemical signature of the pair instability supernova is more prominent, because most of them are born as single stars.« less

Authors:
;  [1];  [2]
  1. Department of Physics, Konan University, Okamoto, Kobe (Japan)
  2. Center for Computational Science, University of Tsukuba (Japan)
Publication Date:
OSTI Identifier:
22365216
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 792; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; ELECTROMAGNETIC PULSES; EQUILIBRIUM; HYDRODYNAMICS; INSTABILITY; INTERACTIONS; LYMAN LINES; MASS; MASS SPECTRA; METALLICITY; METALS; SIMULATION; STARS; THREE-BODY PROBLEM; THREE-DIMENSIONAL CALCULATIONS; UNIVERSE

Citation Formats

Susa, Hajime, Tominaga, Nozomu, and Hasegawa, Kenji, E-mail: susa@konan-u.ac.jp. The mass spectrum of the first stars. United States: N. p., 2014. Web. doi:10.1088/0004-637X/792/1/32.
Susa, Hajime, Tominaga, Nozomu, & Hasegawa, Kenji, E-mail: susa@konan-u.ac.jp. The mass spectrum of the first stars. United States. doi:10.1088/0004-637X/792/1/32.
Susa, Hajime, Tominaga, Nozomu, and Hasegawa, Kenji, E-mail: susa@konan-u.ac.jp. Mon . "The mass spectrum of the first stars". United States. doi:10.1088/0004-637X/792/1/32.
@article{osti_22365216,
title = {The mass spectrum of the first stars},
author = {Susa, Hajime and Tominaga, Nozomu and Hasegawa, Kenji, E-mail: susa@konan-u.ac.jp},
abstractNote = {We perform cosmological hydrodynamics simulations with non-equilibrium primordial chemistry to obtain 59 minihalos that host first stars. The obtained minihalos are used as the initial conditions of local three-dimensional radiation hydrodynamics simulations to investigate the formation of the first stars. We find that two-thirds of the minihalos host multiple stars, while the other third has single stars. The mass of the stars found in our simulations are in the range of 1 M {sub ☉} ≲ M ≲ 300 M {sub ☉}, peaking at several× 10 M {sub ☉}. Most of the very massive stars of ≳ 140 M {sub ☉} are born as single stars, although not all of the single stars are very massive. We also find a few stars of ≲ 1 M {sub ☉} that are kicked by the gravitational three body interactions to the position distant from the center of mass. The frequency that a star forming minihalo contains a binary system is ∼50%. We also investigate the abundance pattern of the stellar remnants by summing up the contributions from the first stars in the simulations. Consequently, the pattern is compatible with that of the low metallicity damped Lyα systems or the extremely metal-poor (EMP) stars, if the mass spectrum obtained in our experiment is shifted to the low mass side by 0.2 dex. If we consider the case that an EMP star is born in the remnant of the individual minihalo without mixing with others, the chemical signature of the pair instability supernova is more prominent, because most of them are born as single stars.},
doi = {10.1088/0004-637X/792/1/32},
journal = {Astrophysical Journal},
number = 1,
volume = 792,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}
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