Diagnosing Mass Flows Around Herbig Ae/Be Stars Using the He I 10830 Line

Abstract

We examine He I 10830 profile morphologies for a sample of 56 Herbig Ae/Be stars (HAEBES). We find significant differences between HAEBES and CTTSs in the statistics of both blue-shifted absorption (i.e. mass outflows) and red-shifted absorption features (i.e. mass infall or accretion). Our results suggest that, in general, Herbig Be (HBe) stars do not accrete material from their inner disks in the same manner as CTTSs, which are believed to accrete material via magnetospheric accretion, while Herbig Ae (HAe) stars generally show evidence for magnetospheric accretion. We find no evidence in our sample of narrow blue--shifted absorption features which are typical indicators of inner disk winds and are common in He I 10830 profiles of CTTSs. The lack of inner disk wind signatures in HAEBES, combined with the paucity of detected magnetic fields on these objects, suggests that accretion through large magnetospheres which truncate the disk several stellar radii above the surface is not as common for HAe and late-type HBe stars as it is for CTTSs. Instead, evidence is found for smaller magnetospheres in the maximum red-shifted absorption velocities in our HAEBE sample. These velocities are, on average, a smaller fraction of the system escape velocity than is found for CTTSs, suggesting accretion is taking place closer to the star. Smaller magnetospheres, and evidence for boundary layer accretion in HBe stars, may explain the less common occurrence of red--shifted absorption in HAEBES. Evidence is found that smaller magnetospheres may be less efficient at driving outflows compared to CTTS magnetospheres.

23 pages, 9 figures, 6 tables

References in corpus (21)

• The Magnetic Fields of Classical T Tauri Stars
• Accretion Rates in Herbig Ae stars
• Magnetospheric accretion-ejection processes in the classical T Tauri star AA
• Probing T Tauri Accretion and Outflow with 1 Micron Spectroscopy
• The origin of hydrogen line emission for five Herbig Ae/Be stars spatially resolved by VLTI/AMBER spectro-interferometry
• A hot compact dust disk around a massive young stellar object
• A search for strong, ordered magnetic fields in Herbig Ae/Be stars
• Modeling T Tauri Winds from He I 10830 Profiles
• On the origin of the X-ray emission from Herbig Ae/Be stars
• Magnetocentrifugally Driven Flows from Young Stars and Disks. VI. Accretion with a Multipole Stellar Field
• Accretion-related properties of Herbig Ae/Be stars. Comparison with T Tauris
• Redshifted Absorption at He I 10830 as a Probe of the Accretion Geometry of T Tauri Stars
• Optical spectroscopic variability of Herbig Ae/Be stars
• Spectrally Dispersed K-Band Interferometric Observations of Herbig Ae/Be Sources: Inner Disk Temperature Profiles
• Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD104237
• On the difference between Herbig Ae and Herbig Be stars
• Discovery of an Optically Thick, Edge-on Disk around the Herbig Ae star PDS 144N
• Further X-ray detections of Herbig stars
• Spectral atlas of massive stars around He I 10830 A
• Molecular hydrogen in the circumstellar environments of Herbig Ae/Be stars probed by FUSE
• Emission-line profile modelling of structured T Tauri magnetospheres

Cited by in corpus (18)

• An ALMA survey of DCN/H${}^{13}$CN and DCO${}^{+}$/H${}^{13}$CO${}^{+}$ in protoplanetary disks
• Catalogue of new Herbig Ae/Be and classical Be stars. A machine learning approach to Gaia DR2
• A spectroscopic survey of Herbig Ae/Be stars with X-Shooter II: Accretion diagnostic lines
• The compact H$\alpha$ emitting regions of the Herbig Ae/Be stars HD 179218 and HD 141569 from CHARA spectro-interferometry
• The prevalence of weak magnetic fields in Herbig Ae stars: The case of PDS2
• On the Mass Accretion Rates of Herbig Ae/Be Stars. Magnetospheric Accretion or Boundary Layer?
• A "Rosetta Stone" for protoplanetary disks: The synergy of multi-wavelength observations
• Tracing Accretion onto Herbig Ae/Be Stars Using the Brγ Line
• The Eruption of the Candidate Young Star ASASSN-15qi
• Linking Signatures of Accretion with Magnetic Field Measurements - Line Profiles are not Significantly Different in Magnetic and Non-Magnetic Herbig Ae/Be Stars
• The He I $\lambda$10830 $\mathring{A}$ line as a probe of winds and accretion in young stars in Lupus and Upper Scorpius
• High-cadence, High-resolution Spectroscopic Observations of Herbig Stars HD 98922 and V1295 Aquila
• Globules and pillars in Cygnus X III. Herschel and upGREAT/SOFIA far-infrared spectroscopy of the globule IRAS 20319+3958 inCygnus X
• Modelling UX Ori Star Eclipses based on Spectral Observations with the Nordic Optical Telescope. I. RR Tau
• Near-infrared spectroscopy of embedded protostars in the massive metal-poor star-forming region NGC 346
• Understanding the angular momentum evolution of T Tauri and Herbig Ae/Be stars
• Spectropolarimetry of stars across the H-R diagram
• The CARMENES search for exoplanets around M dwarfs. The He I triplet at 10830 $\mathring{\mathrm{A}}$ across the M dwarf sequence