CHEMICAL EVOLUTION OF TURBULENT PROTOPLANETARY DISKS AND THE SOLAR NEBULA

By D. Semenov, D. Wiebe. 2011

137 citations recorded by the source corpus.

We study the influence of transport processes on the chemical evolution of DM Tau-like protoplanetary disks. Turbulent transport of gases and ices is implicitly modeled in full two dimensions (2D), using the mixing-length approximation, along with the time-dependent chemistry. We find that turbulent transport enhances abundances and column densities of many gas-phase species and ices, particularly, complex ones. The influence of turbulent mixing on disk chemistry is more pronounced in the inner, planet-forming disk region where gradients of temperature and high-energy radiation intensities are steeper than in the outer region. The molecules that are unresponsive to transport include, e.g., C2H, C+, CH4, CN, CO, HCN, HNC, H2CO, OH, as well as water and ammonia ice. Their column densities computed with the laminar and 2D mixing model differ by a factor of ≲ 2–5. Molecules whose vertical column densities in the laminar and dynamical models differ by up to two orders of magnitude include, e.g., C2H2, some carbon chains, CS, H2CS, H2O, HCO+, HCOOH, HNCO, N2H+, NH3, CO ice, H2CO ice, CH3OH ice, and electrons. Molecules whose column densities are altered by diffusion by more than two orders of magnitude include, e.g., C2S, C3S, C6H6, CO2, O2, SiO, SO, SO2, long carbon chain ices, CH3CHO ice, HCOOH ice, O2 ice, and OCN ice. We indicate several observable or potentially detectable tracers of transport processes in protoplanetary disks and the solar nebula, such as heavy hydrocarbon ices, complex organics, CO2, O2, SO, SO2, C2S, C3S compared to CO and water ice.

Subfields: Astronomy and Astrophysics, Spectroscopy

View Paper: https://www.semanticscholar.org/paper/d40cb9e567ae0809dc9dded5e2c754c14561ff45

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

In Spectroscopy

Citations in the corpus

A PARAMETRIC MODELING APPROACH TO MEASURING THE GAS MASSES OF CIRCUMSTELLAR DISKS (2013, result): “We note, however, the contrary point made by Semenov & Wiebe (2011) that the CO chemical timescale is shorter than the diffusion timescale and therefore that its abundance should not be strongly affected by transport.”
A Three-dimensional View of Turbulence: Constraints on Turbulent Motions in the HD 163296 Protoplanetary Disk Using DCO+ (2017, background): “Turbulent eddies can lead to mixing of chemical species in the vertical direction (Semenov & Wiebe 2011; Furuya & Aikawa 2014).”
Retrieving scattering clouds and disequilibrium chemistry in the atmosphere of HR 8799e (2020, methodology): “The chemical model is based on the gas-grain code ALCHEMIC (Semenov & Wiebe 2011) with desorption energies updated according to Cuppen et al. (2017).”
A SPATIALLY RESOLVED VERTICAL TEMPERATURE GRADIENT IN THE HD 163296 DISK (2013, background): “Detailed radiative transfer and chemical models (Aikawa & Herbst 1999; Aikawa & Nomura 2006; Semenov & Wiebe 2011; Walsh et al. 2012) predict a cone-like structure for molecules like CO.”
Turbulence in the TW Hya Disk (2018, methodology): “Chemical mixing of the gas will depend on the turbulence (Semenov & Wiebe 2011), which in 1 Van Vleck Observatory, Astronomy Department, Wesleyan University, 96 Foss Hill Drive, Middletown, CT 06459 2 Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 3 Department…”
Survival of molecular gas in cavities of transition disks - I. CO (2013, background): “While the chemical time-scales are usually short, mixing in vertical or radial direction could smooth out transitions (e.g. Ilgner & Nelson 2006; Heinzeller et al. 2011; Semenov & Wiebe 2011).”
Equilibrium chemistry down to 100 K (2017, background): “…generally expected to occur in diluted gases, in particular due to UV-fields, X-rays or cosmic rays as, for example, in protoplanetary discs (e.g. Semenov & Wiebe 2011; Woitke et al. 2016), in the upper layers of planetary atmospheres (e.g. Moses 2014; Rimmer & Helling 2016), or in case of fast…”
Complex organic molecules in protoplanetary disks (2013, background): “Protoplanetary disks are turbulent environments and the effects of vertical turbulent mixing on disk chemical structure has been investigated by multiple groups (see, e.g., Ilgner et al. 2004; Willacy et al. 2006; Semenov et al. 2006; Aikawa 2007; Heinzeller et al. 2011; Semenov & Wiebe 2011).”
WEAK TURBULENCE IN THE HD 163296 PROTOPLANETARY DISK REVEALED BY ALMA CO OBSERVATIONS (2015, background): “Given that turbulence operates over a typical length scale of H, it more strongly affects the steeper vertical chemical gradients than the shallower radial gradients (Semenov & Wiebe 2011) and is unlikely to strongly affect the radial location of e.g., the CO snow line.”
Molecules with ALMA at Planet-forming Scales (MAPS). I. Program Overview and Highlights (2021, background): “It is, however, important to note that protoplanetary disks are dynamical objects and that this can have a large impact on the distribution of molecules (e.g., Willacy 2007; Semenov & Wiebe 2011; Akimkin et al. 2013; Rab et al. 2017; Price et al. 2020).”