Evolution of Dust and Water Ice in Cometary Comae by Radiative Torques
arXiv:2005.10446 · doi:10.3847/1538-4357/abafa5
Abstract
Comets provide unique information about the physical and chemical properties of the environment in which the Solar system was formed. Understanding how cometary dust and ice evolve under the effect of sunlight is essential for constraining nuclear structure and triggering mechanism of comet activity. In this paper, we first study rotational disruption of dust grains lifted by outgassing from comet nuclei by radiative torques (RATs). We find that composite grains could be rapidly disrupted into small fragments by the Radiative Torque Disruption (RATD) mechanism. We then study rotational desorption of ice grains by RATs and find that icy grains could be desorbed from large heliocentric distances, beyond the sublimation radius of water at $R_{\rm sub}(\H_{2}Ø)\sim 3\AU$. We also calculate the production rate of water vapor versus the heliocentric distance of comets due to rotational desorption. Our results could explain the variation of dust properties and the presence of small grains frequently observed from cometary comae. Finally, we suggest that the activity of distant comets could be triggered by rotational disruption of grains and desorption of water ice grains at large heliocentric distances.
arXiv comment16 pages, 10 figures; accepted to ApJ
References in corpus (32)
- Electric Dipole Radiation from Spinning Dust Grains
- Radiative torques: Analytical Model and Basic Properties
- Radiative Torques on Interstellar Grains: I. Superthermal Spinup
- The Active Centaurs
- Radiative torque alignment: Essential Physical Processes
- The Efficiency of Grain Alignment in Dense Interstellar Clouds: A Reassessment of Constraints from Near Infrared Polarization
- A unified model of grain alignment: radiative alignment of interstellar grains with magnetic inclusions
- Synthesis of the Morphological Description of Cometary Dust at Comet 67P
- Water Ice and Dust in the Innermost Coma of Comet 103P/Hartley 2
- Grain Alignment by Radiative Torques in Special Conditions and Implications
- Rotational Disruption of Dust Grains by Radiative Torques in Strong Radiation Fields
- Improving the model of emission from spinning dust: effects of grain wobbling and transient spin-up
- CO in distantly active comets
- Main-Belt Comet P/2008 R1 (Garradd)
- Explosion of Comet 17P/Holmes as revealed by the Spitzer Space Telescope
- Radiative torques alignment in the presence of pinwheel torques
- Comet 17P/Holmes in Outburst: The Near Infrared Spectrum
- A dynamical constraint on interstellar dust models from radiative torque disruption
- Spinning Dust Emission: Effects of irregular grain shape, transient heating and comparison with WMAP results
- Davis-Greenstein alignment of oblate spheroidal grains
- Science Impacts of the SPHEREx All-Sky Optical to Near-Infrared Spectral Survey II: Report of a Community Workshop on the Scientific Synergies Between the SPHEREx Survey and Other Astronomy Observatories
- Circular polarization in comets: Observations of Comet C/1999 S4 (LINEAR) and tentative interpretation
- Magnetic Properties of Dust Grains, Effect of Precession and Radiative Torque Alignment
- The tensile strength of dust aggregates consisting of small elastic grains: Constraints on the size of condensates in protoplanetary disks
- Radiative torques of irregular grains: Describing the alignment of a grain ensemble
- Rotational Desorption of Ice Mantles and Complex Molecules from Suprathermally Rotating Dust Grains around Young Stellar Objects
- Evidence of Fragmenting Dust Particles from Near-Simultaneous Optical and Near-IR Photometry and Polarimetry of Comet 73P/Schwassmann-Wachmann 3
- Optical and Near-Infrared Polarimetry of Non-Periodic Comet C/2013 US10 (Catalina)
- Chemistry on Rotating Grain Surface: Ro-Thermal Desorption of Molecules from Ice Mantles
- Near-Infrared Polarimetric Study of Near-Earth Object 252P/LINEAR: An Implication of Scattered Light from the Evolved Dust Particles
- Rotational Disruption of Nonspherical Cometary Dust Particles by Radiative Torques
- Comet 2P/Encke in apparition of 2017: II. Polarization and color