The IGRINS YSO Survey. III. Stellar Parameters of Pre-main-sequence Stars in Ophiuchus and Upper Scorpius
Abstract

We used the Immersion GRating Infrared Spectrometer (IGRINS) to determine fundamental parameters for 61 K- and M-type young stellar objects (YSOs) located in the Ophiuchus and Upper Scorpius star-forming regions. We employed synthetic spectra and a Markov chain Monte Carlo approach to fit specificK-band spectral regions and determine the photospheric temperature (T), surface gravity ($logg$), magnetic field strength (B), projected rotational velocity ($vsini$), andK-band veiling (rK). We determinedBfor ∼46% of our sample. Stellar parameters were compared to the results from Taurus-Auriga and the TW Hydrae association presented in Paper I of this series. We classified all the YSOs in the IGRINS survey with infrared spectral indices from Two Micron All Sky Survey and Wide-field Infrared Survey Explorer photometry between 2 and 24μm. We found that Class II YSOs typically have lower$logg$and$vsini$, similarB, and higherK-band veiling than their Class III counterparts. Additionally, we determined the stellar parameters for a sample of K and M field stars also observed with IGRINS. We have identified intrinsic similarities and differences at different evolutionary stages with our homogeneous determination of stellar parameters in the IGRINS YSO survey. Considering$logg$as a more »

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10392920
Journal Name:
The Astrophysical Journal
Volume:
943
Issue:
1
Page Range or eLocation-ID:
Article No. 49
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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