Photoevaporation of Grain-depleted Protoplanetary Disks around Intermediate-mass Stars: Investigating the Possibility of Gas-rich Debris Disks as Protoplanetary Remnants
نویسندگان
چکیده
Debris disks are classically considered to be gas-less systems, but recent (sub)millimeter observations have detected tens of those with rich gas content. The origin the component remains unclear; namely, it can protoplanetary remnants and/or secondary products deriving from large bodies. In order in origin, parental disk is required survive for $\gtrsim10{\,\rm Myr}$. However, previous models predict $\lesssim 10{\,\rm Myr}$ lifetimes because efficient photoevaporation at late stage evolution. present study, we investigate gas-rich, optically-thin around intermediate-mass stars a evolved system modeled as where radiation force sufficiently strong continuously blow out small grains ($\lesssim 4 {\,\rm \mu m}$), which an essential driving via photoelectric heating induced by stellar far-ultraviolet (FUV). We find that grain depletion reduces heating, so FUV not excited. Extreme-ultraviolet (EUV) dominant and yields mass-loss rate $2$--$5\times10^{-10}(\Phi_{\rm EUV}/10^{41}{\,\rm s}^{-1})^{1/2}\,M_\odot\,{\rm yr}^{-1}$, $\Phi_{\rm EUV}$ EUV emission rate. estimated $\sim 50 (M_{\rm disk}/10^{-2}\,M_\odot)(\Phi_{\rm EUV}/10^{41}\,{\rm s}^{-1})^{1/2}\,{\rm depend on ``initial'' mass point been depleted system. With estimation, show much longer time A-type than lower-mass stars. This trend consistent higher frequency gas-rich debris stars, implying possibility being remnants.
منابع مشابه
Photoevaporation of protostellar disks III. The appearance of photoevaporating disks around young intermediate mass stars
We present theoretical continuum emission spectra (SED’s), isophotal maps and line profiles for several models of photoevaporating disks at different orientations with respect to the observer. The hydrodynamic evolution of these models has been the topic of the two previous papers of this series. We discuss in detail the numerical scheme used for these diagnostic radiation transfer calculations...
متن کاملFragmentation of protoplanetary disks around M-dwarfs
We investigate the conditions required for planet formation via gravitational instability (GI) and protoplanetary disk (PPD) fragmentation around M-dwarfs. Using a suite of 64 SPH simulations with 106 particles, the parameter space of disk mass, temperature, and radius is explored, bracketing reasonable values based on theory and observation. Our model consists of an equilibrium, gaseous, and l...
متن کاملProtoplanetary Gas Disks in the Far Infrared
The physical and chemical conditions in young protoplanetary disks set the boundary conditions for planet formation. Although the dust in disks is relatively easily detected as a far-IR photometric “excess” over the expected photospheric emission, much less is known about the gas phase. It seems clear that an abrupt transition from massive optically thick disks (gas–rich structures where only ∼...
متن کاملAstronomy and Astrophysics Photoevaporation of Protostellar Disks Iii. the Appearance of Photoevaporating Disks around Young Intermediate Mass Stars
We present theoretical continuum emission spectra (SED’s), isophotal maps and line profiles for several models of photoevaporating disks at different orientations with respect to the observer. The hydrodynamic evolution of these models has been the topic of the two previous papers of this series. We discuss in detail the numerical scheme used for these diagnostic radiation transfer calculations...
متن کاملTorques as the Viscosity of Protoplanetary Disks
We revisit the idea that density-wave wakes of planets drive accretion in protostel-lar disks. The effects of many small planets can be represented as a viscosity if the wakes damp locally, but the viscosity is proportional to the damping length. Damping occurs mainly by shocks even for earth-mass planets. The excitation of the wake follows from standard linear theory including the torque cutof...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2021
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/1538-4357/ac0137