Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/aea978

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psag135

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Astronomical Society  

Abstract

We developed a one-dimensional magnetohydrodynamic (MHD) simulation code to investigate the long-term evolution of protoplanetary disks with low computational cost. In this simulation code, the physical processes necessary for protostellar formation and protoplanetary disk evolution, such as magnetic braking, nonideal MHD effects, and angular momentum transport due to viscosity, are implemented. Using this simulation code, we performed the simulations of the long-term evolution of protoplanetary disks starting from the molecular cloud. Our simulation results suggest that the disk size and mass are a few tens of astronomical units and ∼0.01 M _⊙ at 10⁵ yr after protostellar formation. These values were relatively consistent with observations. The disk evolves through magnetic braking, and its radial profiles are consistent with the analytical solutions of previous studies. Our simulation code will be an important tool for studying the long-term evolution of protoplanetary disks.

DOI： 10.3847/1538-4357/adf4ea

Scopus

Other Link： https://iopscience.iop.org/article/10.3847/1538-4357/adf4ea/pdf

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

Abstract

In this study, we perform 3D magnetohydrodynamics (MHD) simulations of filamentary molecular clouds. We then generate synthetic observations based on the simulation results. Using these, we investigate how the new polarization data analysis method recently introduced by Doi et al. (2021, ApJ, 923, L9) reflects the magnetic field structure in turbulent filamentary molecular clouds. Doi et al. proposed that the $R_{\rm {FWHM } }$, the ratio of the full width at half maximum (FWHM) of the polarized intensity ($PI$) to that of the total intensity ($I$) can be used to probe the three-dimensional structure of the magnetic field. We calculate the $R_{\rm {FWHM } }$ from the density and magnetic field structure obtained in the 3D-MHD simulations. We find that the mean and variance of $R_{\rm {FWHM } }$ within a filament are smaller and larger, respectively, with a larger inclination of the magnetic field to the plane-of-sky. We also find that both small-scale ($\lt $0.1 pc) and large-scale ($\gtrsim$0.1 pc) turbulence affect the polarized intensity of the dust thermal emission. We conclude that future extensive observations of $R_{\rm {FWHM } }$ may be able to quantify the inclination of the magnetic field to the plane-of-sky in the filamentary molecular clouds.

DOI： 10.1093/pasj/psae115

Scopus

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Astronomical Society  

DOI： 10.3847/1538-4357/ad187a

Scopus

Other Link： https://iopscience.iop.org/article/10.3847/1538-4357/ad187a/pdf

Type：Lecture