On the Stability of Very Massive Primordial Stars

By Isabelle Baraffe, A. Heger, Stan Woosley. 2000

150 citations recorded by the source corpus.

The stability of metal-free very massive stars (Z = 0; M = 120-500 M☉) is analyzed and compared with metal-enriched stars. Such zero-metallicity stars are unstable to nuclear-powered radial pulsations on the main sequence, but the growth timescale for these instabilities is much longer than for their metal-rich counterparts. Since they stabilize quickly after evolving off the zero-age main sequence (ZAMS), the pulsation may not have sufficient time to drive appreciable mass loss in Z = 0 stars. For reasonable assumptions regarding the efficiency of converting pulsational energy into mass loss, we find that, even for the larger masses considered, the star may die without losing a large fraction of its mass. We find a transition between the ϵ- and κ-mechanisms for pulsational instability at Z ~ 2 × 10-4 to 2 × 10-3. For the most metal-rich stars, the κ-mechanism yields much shorter e-folding times, indicating the presence of a strong instability. We thus stress the fundamental difference of the stability and late stages of evolution between very massive stars born in the early universe and those that might be born today.

Subfields: Astronomy and Astrophysics, Instrumentation, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/2db3130e103d9fa1550499ca518b59d20c858ce5

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. N. Smith
2. S. Glover
3. Volker Bromm
4. Ralf Klessen
5. Stan Woosley
6. Tom Abel
7. S. Smartt
8. Christoph Federrath

In Instrumentation

1. N. Smith
2. Ralf Klessen
3. Stan Woosley
4. S. Glover
5. A. Filippenko
6. Weidong Li
7. Robi Banerjee
8. Volker Bromm

In Statistical and Nonlinear Physics

1. A. Ferrara
2. R. Larson
3. S. Glover
4. Ralf Klessen
5. Volker Bromm
6. M. Latif
7. Naoki Yoshida
8. T. Hosokawa

Citations in the corpus

• Line-driven Winds, Ionizing Fluxes, and Ultraviolet Spectra of Hot Stars at Extremely Low Metallicity. I. Very Massive O Stars (2002, background): “A comparison with models of very massive stars published in the literature (see, e.g., Bromm et al. 2001b; Baraffe et al. 2001) shows that this simple extrapolation is quite reliable.”
• FORMATION OF PRIMORDIAL SUPERMASSIVE STARS BY RAPID MASS ACCRETION (2013, background): “Note that the pulsational instability considered above qualitatively differs from that of non-accreting massive primordial stars, which is caused by the ǫ-mechanism (e.g., Baraffe et al. 2001; Sonoi & Umeda 2012).”
• Mass loss from hot massive stars (2008, background): “Interesting possibilities include stellar rotation and pulsations, although pure vibration models for Pop III stars also indicate little mass loss via pulsations alone (Baraffe et al 2001).”
• LIMITING ACCRETION ONTO MASSIVE STARS BY FRAGMENTATION-INDUCED STARVATION (2010, background): “It has been speculated before that radiative stellar feedback might be responsible for this limit (see, e.g., Zinnecker & Yorke 2007) or alternatively that the internal stability limit of stars with non-zero metallicity lies in this mass regime (Appenzeller 1970b,a, 1987; Baraffe et al. 2001).”
• Gravitational Wave Emission from Core Collapse of Massive Stars (2001, background): “As they evolve to collapse in less than a few million years (Baraffe et al. 2001), they will only be observed at the high redshifts of their birth.”
• The First Stars (2003, background): “This is conceivable, as metal-free stars may experience negligible mass loss before exploding as a SN (Baraffe et al. 2001).”
• How Massive Single Stars End Their Life (2002, background): “Therefore, it seems reasonable to assume that at sufficiently low metallicity (Zd10 4 Z ) very massive stars may retain most of their mass through the end of central helium burning, forming a massive helium core (Baraffe et al. 2001; Kudritzki 2002; Marigo, Chiosi, & Kudritzki 2003).”
• Evolution of Dust in Primordial Supernova Remnants: Can Dust Grains Formed in the Ejecta Survive and Be Injected into the Early Interstellar Medium? (2007, background): “It should be mentioned here that the massivemetal-free stars cannot lose significant mass during their lifetime due to pulsations and line-driven stellar winds, which are considered to be important at high metallicities (Baraffe et al. 2001).”
• Physical Processes in the Interstellar Medium (2014, background): “metallicity lies in this mass regime (Appenzeller 1970a, b, 1987; Baraffe et al. 2001).”
• NUCLEOSYNTHESIS AND EVOLUTION OF MASSIVE METAL-FREE STARS (2008, unknown): “…5.30 × 1062 2.46 × 1061 37.0 3.10 × 1062 2.96 × 1063 8.11 × 1062 5.41 × 1062 1.80 × 1063 5.13 × 1062 5.58 × 1062 2.65 × 1061 38.0 3.95 × 1062 3.38 × 1063 8.59 × 1062 5.65 × 1062 1.85 × 1063 5.29 × 1062 5.83 × 1062 2.85 × 1061 39.0 6.87 × 1062 3.80 × 1063 8.58 × 1062 5.66 × 1062 1.89 × 1063 5.49…”