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The Evolution of Disk Winds from a Combined Study of Optical and Infrared Forbidden Lines.
- Source :
- Astrophysical Journal; Nov2020, Vol. 903 Issue 2, p1-19, 19p
- Publication Year :
- 2020
-
Abstract
- We analyze high-resolution (Δv ≤ 10 km s<superscript>−1</superscript>) optical and infrared spectra covering the [O i ] λ6300 and [Ne ii ] 12.81 μm lines from a sample of 31 disks in different evolutionary stages. Following work at optical wavelengths, we use Gaussian profiles to fit the [Ne ii ] lines and classify them into high-velocity component (HVC) or low-velocity component (LVC) if the line centroid is more or less blueshifted than 30 km s<superscript>−1</superscript> with respect to the stellar radial velocity, respectively. Unlike for the [O i ], where an HVC is often accompanied by an LVC, all 17 sources with an [Ne ii ] detection have either an HVC or an LVC. [Ne ii ] HVCs are preferentially detected toward high accretors (M<subscript>⊙</subscript> yr<superscript>−1</superscript>), while LVCs are found in sources with low , low [O i ] luminosity, and large infrared spectral index (n<subscript>13–31</subscript>). Interestingly, the [Ne ii ] and [O i ] LVC luminosities display an opposite behavior with n<subscript>13–31</subscript>: as the inner dust disk depletes (higher n<subscript>13–31</subscript>), the [Ne ii ] luminosity increases while the [O i ] weakens. The [Ne ii ] and [O i ] HVC profiles are generally similar, with centroids and FWHMs showing the expected behavior from shocked gas in microjets. In contrast, the [Ne ii ] LVC profiles are typically more blueshifted and narrower than the [O i ] profiles. The FWHM and centroid versus disk inclination suggest that the [Ne ii ] LVC predominantly traces unbound gas from a slow, wide-angle wind that has not lost completely the Keplerian signature from its launching region. We sketch an evolutionary scenario that could explain the combined [O i ] and [Ne ii ] results and includes screening of hard (∼1 keV) X-rays in inner, mostly molecular, MHD winds. [ABSTRACT FROM AUTHOR]
- Subjects :
- HARD disks
OPTICAL spectra
TRACE gases
INFRARED spectra
CENTROID
Subjects
Details
- Language :
- English
- ISSN :
- 0004637X
- Volume :
- 903
- Issue :
- 2
- Database :
- Complementary Index
- Journal :
- Astrophysical Journal
- Publication Type :
- Academic Journal
- Accession number :
- 147320313
- Full Text :
- https://doi.org/10.3847/1538-4357/abba3c