SIMBAD references

2019ApJ...885...64E - Astrophys. J., 885, 64-64 (2019/November-1)

The nature of class I sources: periodic variables in Orion.


Abstract (from CDS):

We present a quantitative, empirically based argument that at least some Class I sources are low-mass, pre-main-sequence stars surrounded by spatially extended envelopes of dusty gas. The source luminosity arises principally from stellar gravitational contraction, as in optically visible pre-main-sequence stars that lack such envelopes. We base our argument on the fact that some Class I sources in Orion and other star-forming regions have been observed by Spitzer to be periodic variables in the mid-infrared, and with periods consistent with T Tauri rotation rates. Using a radiative transfer code, we construct a variety of dust envelopes surrounding rotating, spotted stars, to see whether an envelope that produces a Class I spectral energy distribution at least broadly matches the observed modulations in luminosity. Acceptable envelopes can be either spherical or flattened and may or may not have polar cavities. The key requirement is that they have a modest equatorial optical depth at the Spitzer waveband of 3.6 µm, typically τ3.6 ≃ 0.6. The total envelope mass, based on this limited study, is at most about 0.1 M, less than a typical stellar mass. Future studies should focus on the dynamics of the envelope, to determine whether material is actually falling onto the circumstellar disk.

Abstract Copyright: © 2019. The American Astronomical Society. All rights reserved.

Journal keyword(s): Circumstellar matter - Pre-main sequence stars - Protostars - Starspots - T Tauri stars - Herbig Ae/Be stars

Status at CDS:   waiting for electronic table
// Large table(s) will be appraised for possible ingestion in VizieR.

Simbad objects: 41

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2019ApJ...885...64E and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact