Characterizing the stellar photospheres and near-infrared excesses in accreting T Tauri systems

Abstract

Using NASA IRTF SpeX data from 0.8 to 4.5 $\mu$m, we determine self-consistently the stellar properties and excess emission above the photosphere for a sample of classical T Tauri stars (CTTS) in the Taurus molecular cloud with varying degrees of accretion. This process uses a combination of techniques from the recent literature as well as observations of weak-line T Tauri stars (WTTS) to account for the differences in surface gravity and chromospheric activity between the TTS and dwarfs, which are typically used as photospheric templates for CTTS. Our improved veiling and extinction estimates for our targets allow us to extract flux-calibrated spectra of the excess in the near-infrared. We find that we are able to produce an acceptable parametric fit to the near-infrared excesses using a combination of up to three blackbodies. In half of our sample, two blackbodies at temperatures of 8000 K and 1600 K suffice. These temperatures and the corresponding solid angles are consistent with emission from the accretion shock on the stellar surface and the inner dust sublimation rim of the disk, respectively. In contrast, the other half requires three blackbodies at 8000, 1800, and 800 K, to describe the excess. We interpret the combined two cooler blackbodies as the dust sublimation wall with either a contribution from the disk surface beyond the wall or curvature of the wall itself, neither of which should have single-temperature blackbody emission. In these fits, we find no evidence of a contribution from optically thick gas inside the inner dust rim.

arXiv commentAccepted to ApJ, 22 pages, 2 appendices, 12 figures, 7 tables

References in corpus (26)

• A Method of Correcting Near-Infrared Spectra for Telluric Absorption
• Passive irradiated circumstellar disks with an inner hole
• The Infrared Telescope Facility (IRTF) Spectral Library: Cool Stars
• Accretion Disks around Young Objects. I. The Detailed Vertical Structure
• ISO spectroscopy of circumstellar dust in 14 Herbig Ae/Be systems: towards an understanding of dust processing
• Observational Constraints on the Formation and Evolution of Binary Stars
• Flaring vs. self-shadowed disks: the SEDs of Herbig Ae/Be stars
• A Survey and Analysis of Spitzer Infrared Spectrograph Spectra of T Tauri Stars in Taurus
• On the Evolutionary Status of Class I Stars and Herbig-Haro Energy Sources in Taurus-Auriga
• Mapping the Shores of the Brown Dwarf Desert II: Multiple Star Formation in Taurus-Auriga
• JHK Standard Stars for Large Telescopes: the UKIRT Fundamental and Extended Lists
• Unveiling the Structure of Pre-Transitional Disks
• Unveiling the Inner Disk Structure of T Tauri Stars
• The Shape of the Inner Rim in Proto-Planetary Disks
• On the Interferometric Sizes of Young Stellar Objects
• Observations and modeling of the inner disk region of T Tauri stars
• Optical Spectroscopy of Embedded Young Stars in the Taurus-Auriga Molecular Cloud
• Characterizing the IYJ Excess Continuum Emission in T Tauri Stars
• Near-Infrared Spectroscopy of TW Hya: A Revised Spectral Type and Comparison with Magnetospheric Accretion Models
• The Inner Rim of YSO Disks: Effects of dust grain evolution
• Strong Near-Infrared Emission Interior to the Dust-Sublimation Radius of Young Stellar Objects MWC275 and AB Aur
• Keck Interferometer observations of classical and weak line T Tauri stars
• Spatially Resolved Spectroscopy of Sub-AU-Sized Regions of T Tauri and Herbig Ae/Be Disks
• Far-Ultraviolet H2 Emission from Circumstellar Disks
• Spectrally Dispersed K-Band Interferometric Observations of Herbig Ae/Be Sources: Inner Disk Temperature Profiles
• High Resolution K-band Spectroscopy of MWC 480 and V1331 Cyg

Cited by in corpus (41)

• An Optical Spectroscopic Study of T Tauri Stars. I. Photospheric Properties
• Placing the spotted T Tauri star LkCa 4 on an HR diagram
• High resolution millimetre imaging of the CI Tau protoplanetary disc - a massive ensemble of protoplanets from 0.1 - 100 au
• Spectroscopic Confirmation of Young Planetary-Mass Companions on Wide Orbits
• An empirical sequence of disk gap opening revealed by rovibrational CO
• Carbon depletion observed inside T Tauri inner rims: Formation of icy, kilometer size planetesimals by 1 Myr
• Curved walls: Grain growth, settling, and composition patterns in T Tauri disk dust sublimation fronts
• Detections of trans-Neptunian ice in protoplanetary disks
• The evolution of accretion in young stellar objects: Strong accretors at 3 - 10 Myr
• Direct Measurement of Interstellar Extinction Toward Young Stars Using Atomic Hydrogen Lyman-$\alpha$ Absorption
• Using FUV to IR Variability to Probe the Star-Disk Connection in the Transitional Disk of GM Aur
• CO Detected in CI Tau b: Hot Start Implied by Planet Mass and M${}_K$
• A Herschel view of protoplanetary disks in the $\sigma$ Ori cluster
• Tracing pebble drift and trapping using radial carbon depletion profiles in protoplanetary disks
• Depletion of molecular gas by an accretion outburst in a protoplanetary disk
• Spitzer Observations of Long Term Infrared Variability Among Young Stellar Objects in Chamaeleon I
• K2 reveals pulsed accretion driven by the 2 Myr old hot Jupiter CI Tau b
• Measuring the atomic composition of planetary building blocks
• New insights on the near-infrared veiling of young stars using CFHT/SPIRou data
• Anomalous Accretion Activity and the Spotted Nature of the DQ Tau Binary System
• The ESO SupJup Survey II: The 12C/13C ratios of three young brown dwarfs with CRIRES${}^{+}$
• Connecting X-ray and Infrared Variability among Young Stellar Objects: Ruling out potential sources of disk fluctuations
• Structure and Dynamics of the Accretion Process and Wind in TW Hya
• T Tauri Stars: Physical Parameters and Evolutionary Status
• The Inner Disk and Accretion Flow of the Close Binary DQ Tau
• Herschel Observations of Protoplanetary Disks in Lynds 1641
• Measuring Optical Extinction Towards Young Stellar Objects Using Diffuse Interstellar Bands
• High-resolution TNG spectra of T Tauri stars: Near-IR GIANO observations of the young variables XZ Tau and DR Tau
• Modeling of CoRoT and Spitzer lightcurves in NGC 2264 caused by an optically thick warp
• Constraints on the height of the inner disk rim in pre-main-sequence stars
• Lyman-alpha Scattering Models Trace Accretion and Outflow Kinematics in T Tauri Systems
• Ro-vibrational Spectroscopy of CI Tau -- Evidence of a Multi-Component Eccentric Disk Induced by a Planet
• Disk Dissipation Timescale of Pre-main Sequence Stars in Taurus
• Optical and Near-Infrared Excesses are Correlated in T Tauri Stars
• Near-Infrared Variability of Low Mass Stars in IC 1396A and TR 37
• RW Aur A : SpeX Spectral Evidence for Differentiated Planetesimal Formation, Migration and Destruction in an 3 Myr Old Excited CTTS System
• Externally irradiated young stars in NGC 3603. A JWST NIRSpec catalogue of pre-main-sequence stars in a massive star formation region
• CI Tau: A controlled experiment in disk-planet interaction
• Probing Signatures of a Distant Planet around the Young T-Tauri Star CI Tau Hosting a Possible Hot Jupiter
• Disentangling disc and atmospheric signatures of young brown dwarfs with JWST/NIRSpec
• Kinematic evidence of magnetospheric accretion for Herbig Ae stars with JWST NIRSpec