Revealing the Star-Disk-Jet Connection in GM Aur using Multiwavelength Variability

Abstract

Here we analyze the first simultaneous X-ray, ultraviolet, optical, infrared, and centimeter observations of a T Tauri star (TTS). We present three epochs of simultaneous Spitzer and VLA data of GM Aur separated by ~1 wk. These data are compared to previously published HST and Chandra observations from which mass accretion rates ($\dot{M}$) and X-ray luminosities, respectively, were measured. The mid-infrared emission increases along with $\dot{M}$, and we conclude that this is due to an increase in the mass in the inner disk. The cm emission, which probes the jet, also appears to increase as $\dot{M}$ increases, and the changes in the cm flux are consistent with the variability in $\dot{M}$ assuming the mass-loss rate is ~10% $\dot{M}$. The 3 cm emission morphology also appears changed compared with observations taken three years previously, suggesting that for the first time, we may be tracking changes in the jet morphology of a TTS. The X-ray luminosity is constant throughout the three epochs, ruling out variable high-energy stellar radiation as the cause for the increases in the mid-infrared or cm emission. Tying together the multiwavelength variability observed, we conclude that an increase in the surface density in the inner disk resulted in more mass loading onto the star and therefore a higher $\dot{M}$, which led to a higher mass-loss rate in the jet. These results stress the importance of coordinated multiwavelength work to better understand the star-disk-jet connection.

accepted to ApJL

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Cited by in corpus (6)

• Characterizing the dust content of disk substructures in TW Hya
• Stable accretion and episodic outflows in the young transition disk system GM Aurigae
• Optical and Near-Infrared Excesses are Correlated in T Tauri Stars
• A Study of Millimeter Variability in FUor Objects
• Radio multiwavelength analysis of the compact disk CX Tau: Presence of strong free-free variability or anomalous microwave emission
• Understanding Accretion Variability Through TESS Observations of Taurus