Rotational disruption of dust grains by radiative torques in strong radiation fields

Autor: Le Ngoc Tram, Sang-Hyeon Ahn, Thiem Hoang, Hyeseung Lee
Přispěvatelé: Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)
Rok vydání: 2019
Předmět:
010504 meteorology & atmospheric sciences
Astrophysics::High Energy Astrophysical Phenomena
Solar luminosity
FOS: Physical sciences
Astrophysics::Cosmology and Extragalactic Astrophysics
Astrophysics
Radiation
01 natural sciences
0103 physical sciences
Radiative transfer
Astrophysics::Solar and Stellar Astrophysics
010303 astronomy & astrophysics
Solar and Stellar Astrophysics (astro-ph.SR)
Astrophysics::Galaxy Astrophysics
0105 earth and related environmental sciences
High Energy Astrophysical Phenomena (astro-ph.HE)
Physics
Astronomy and Astrophysics
Astrophysics - Astrophysics of Galaxies
Galaxy
Stars
Wavelength
Supernova
Star cluster
Astrophysics - Solar and Stellar Astrophysics
13. Climate action
Astrophysics of Galaxies (astro-ph.GA)
Astrophysics::Earth and Planetary Astrophysics
Astrophysics - High Energy Astrophysical Phenomena
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Zdroj: Nat.Astron.
Nat.Astron., 2019, 3 (8), pp.766-775. ⟨10.1038/s41550-019-0763-6⟩
Nature Astron.
Nature Astron., 2019, 3 (8), pp.766-775. ⟨10.1038/s41550-019-0763-6⟩
ISSN: 2397-3366
Popis: Massive stars, supernovae, and kilonovae are among the most luminous radiation sources in the universe. Observations usually show near- to mid-infrared (NIR--MIR, $\lambda\sim 1-5~\mu$m) emission excess from H\,{\sc ii} regions around young massive star clusters (YMSCs). Early phase observations in optical to NIR wavelengths of type Ia supernovae also reveal unusual properties of dust extinction and dust polarization. The popular explanation for such NIR-MIR excess and unusual dust properties is the predominance of small grains (size $a\lesssim 0.05~\mu$m) relative to large grains ($a\gtrsim 0.1~\mu$m) in the local environment of these strong radiation sources. The question of why small grains are predominant in these environments remains a mystery. Here we report a new mechanism of dust destruction based on centrifugal stress within extremely fast-rotating grains spun-up by radiative torques, which we term the RAdiative Torque Disruption (RATD) mechanism. We find that RATD can disrupt large grains located within a distance of $\sim 1$ pc from a massive star of luminosity $L\sim 10^{4}L_{\odot}$ or a supernova. This effect increases the abundance of small grains relative to large grains and successfully reproduces the observed NIR-MIR excess and anomalous dust extinction/polarization. We apply the RATD mechanism for kilonovae and find that dust within $\sim$ 0.1 pc would be dominated by small grains. Small grains produced by RATD can also explain the steep far-UV rise in extinction curves toward starburst and high redshift galaxies, and the decrease of the escape fraction of Ly$\alpha$ photons from H\,{\sc ii} regions surrounding YMSCs.
Comment: Published on 6 May, 2019
Databáze: OpenAIRE
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