Possible Counter Rotation between the Disk and Protostellar Envelope around the Class I Protostar IRAS 04169+2702

Abstract

We present results from our SMA observations and data analyses of the SMA archival data of the Class I protostar IRAS 04169+2702. The high-resolution (~0.5") ${}^{13}$CO (3-2) image cube shows a compact ($r$ ~< 100 au) structure with a northwest (blue) to southeast (red) velocity gradient, centered on the 0.9-mm dust-continuum emission. The direction of the velocity gradient is orthogonal to the axis of the molecular outflow as seen in the SMA ${}^{12}$CO (2-1) data. A similar gas component is seen in the SO (6${}_5$-5${}_4$) line. On the other hand, the C${}^{18}$O (2-1) emission traces a more extended ($r$ ~400 au) component with the opposite, northwest (red) to southeast (blue) velocity gradient. Such opposite velocity gradients in the different molecular lines are also confirmed from direct fitting to the visibility data. We have constructed models of a forward-rotating and counter-rotating Keplerian disk and a protostellar envelope, including the SMA imaging simulations. The counter-rotating model could better reproduce the observed velocity channel maps, although we could not obtain statistically significant fitting results. The derived model parameters are; Keplerian radius of 200 au, central stellar mass of 0.1 $M_{solar}$, and envelope rotational and infalling velocities of 0.20 km s${}^{-1}$ and 0.16 km s${}^{-1}$, respectively. One possible interpretation for these results is the effect of the magnetic field in the process of disk formation around protostars, $i.e.$, Hall effect.

22 pages, 15 figures

References in corpus (16)

• Magnetic Braking and Protostellar Disk Formation: The Ideal MHD Limit
• Magnetic Fields in Dark Cloud Cores: Arecibo OH Zeeman Observations
• Formation of a Keplerian disk in the infalling envelope around L1527 IRS: transformation from infalling motions to Kepler motions
• Radiation Magnetohydrodynamic Simulations of Protostellar Collapse: Non-Ideal Magnetohydrodynamic Effects and Early Formation of Circumstellar Disks
• Chains of dense cores in the Taurus L1495/B213 complex
• Signs of Early-Stage Disk Growth Revealed with ALMA
• Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?
• Effects of Ohmic and ambipolar diffusion on the formation and evolution of the first cores, protostars and circumstellar discs
• ALMA Observations of the Protostar L1527 IRS: Probing Details of the Disk and the Envelope Structures
• Circumstellar disks and outflows in turbulent molecular cloud cores: possible formation mechanism for misaligned systems
• The impact of the Hall effect during cloud core collapse:implications for circumstellar disk evolution
• Spiral Arms, Infall, and Misalignment of the Circumbinary Disk from the Circumstellar Disks in the Protostellar Binary System L1551 NE
• ALMA observations of the kinematics and chemistry of disc formation
• On the Role of Pseudodisk Warping and Reconnection in Protostellar Disk Formation in Turbulent Magnetized Cores
• 1000 AU Exterior Arcs Connected to the Protoplanetary Disk around HL Tau
• Testing protostellar disk formation models with ALMA observations

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