J/ApJ/911/138 Low-mass pre-main-sequence stars in Taurus-Auriga (Nofi+, 2021)
Projected rotational velocities and fundamental properties of low-mass
pre-main-sequence stars in the Taurus-Auriga star-forming region.
Nofi L.A., Johns-Krull C.M., Lopez-Valdivia R., Biddle L., Carvalho A.S.,
Huber D., Jaffe D., Llama J., Mace G., Prato L., Skiff B., Sokal K.R.,
Sullivan K., Tayar J.
<Astrophys. J., 911, 138 (2021)>
=2021ApJ...911..138N 2021ApJ...911..138N
ADC_Keywords: Stars, pre-main sequence; Spectra, infrared; Optical;
Rotational velocities; Stars, diameters; Effective temperatures
Keywords: Stellar rotation ; Pre-main-sequence stars ; Low-mass stars ;
Fundamental parameters of stars ; High-resolution spectroscopy
Abstract:
The projected stellar rotational velocity (vsini) is critical for our
understanding of processes related to the evolution of angular
momentum in pre-main-sequence stars. We present vsini measurements of
high-resolution infrared and optical spectroscopy for
70 pre-main-sequence stars in the Taurus-Auriga star-forming region,
in addition to effective temperatures measured from line-depth ratios,
as well as stellar rotation periods determined from optical
photometry. From the literature, we identified the stars in our sample
that show evidence of residing in circumstellar disks or multiple
systems. The comparison of infrared vsini measurements calculated
using two techniques shows a residual scatter of ∼1.8km/s, defining a
typical error floor for the vsini of pre-main-sequence stars from
infrared spectra. A comparison of the vsini distributions of stars
with and without companions shows that binaries/multiples typically
have a higher measured vsini, which may be caused by contamination by
companion lines, shorter disk lifetimes in binary systems, or tidal
interactions in hierarchical triples. A comparison of optical and
infrared vsini values shows no significant difference regardless of
whether the star has a disk or not, indicating that CO contamination
from the disk does not impact vsini measurements above the typical
∼1.8km/s error floor of our measurements. Finally, we observe a lack
of a correlation between the vsini, presence of a disk, and H-R
diagram position, which indicates a complex interplay between stellar
rotation and evolution of pre-main-sequence stars.
Description:
The infrared spectral observations used to measure the Teff and the
vsini were obtained using the Immersion GRating INfrared Spectrometer
(IGRINS) at both the 2.7m Harlan J. Smith Telescope at McDonald
Observatory, and the 4.3m Lowell Discovery Telescope between
2014 October and 2018 March. IGRINS is a high-resolution (R∼45000)
near-infrared spectrograph with no moving parts that simultaneously
records the H and K bands (1.4-2.5um). See Section 2.2.1.
In addition to the infrared spectroscopy, we also obtained optical
high-resolution (R∼60000) spectra at McDonald Observatory as part of
the ongoing search for substellar companions to young stars. Starting
in 2004 and continuing to the present time, spectra have been obtained
primarily with the McDonald Observatory 2.7m Harlan J. Smith telescope
coupled to the Robert G. Tull cross-dispersed coude echelle
spectrograph. A smaller number of stars have been observed with the
2.1m Otto Struve telescope coupled to the Sandiford echelle cassegrain
spectrometer. See Section 2.2.2.
We obtained ground-based photometry for many of our targets, to
determine stellar rotation periods. Our ground-based photometry comes
from seasonal V-band monitoring of the sample stars using the Lowell
0.7m robotic telescope. The stars have generally been observed for
about ten nights per month from September through March each year
since 2012, using CCD differential aperture photometry. Additionally,
we obtained rotation periods for several of our sample targets from
the K2 long-cadence time-series photometry observed during Campaign 13
between 2017 March 8 and 2017 May 27 UTC. See Section 2.2.3.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 121 70 Stellar properties of pre-main sequence stars
--------------------------------------------------------------------------------
See also:
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
J/A+AS/101/485 : Multisite UBVRI photometry in Tau-Aur cloud (Bouvier+ 1993)
J/ApJS/95/535 : Infrared CO line list for X1Σ+state (Goorvitch, 1994)
J/A+A/299/89 : COYOTES II (Bouvier+, 1995)
J/A+AS/145/187 : uvby-β photometry of WTTS (Chavarria-K+, 2000)
J/A+A/396/513 : Stellar Rotation in the Orion Nebula Cluster (Herbst+, 2002)
J/ApJ/601/979 : vsini of Orion low-mass stars (Wolff+, 2004)
J/A+A/430/1005 : VRIHα photometry of NGC 2264 variables (Lamm+, 2005)
J/AJ/129/363 : Sp. in Orion Nebula Cluster (Sicilia-Aguilar+, 2005)
J/A+A/450/681 : Companions to close sp. binaries (Tokovinin+, 2006)
J/A+A/467/785 : SuperWASP/ROSAT periodic variable stars (Norton+, 2007)
J/A+A/479/827 : UBVR LCs of weak-line T Tauri stars (Grankin+, 2008)
J/ApJ/704/531 : The coevality of young binary systems (Kraus+, 2009)
J/ApJ/745/56 : Upper Sco members rotational velocities (Dahm+, 2012)
J/ApJ/745/19 : Binary systems in Taurus-Auriga (Kraus+, 2012)
J/ApJ/745/119 : Close companions to young stars. I. (Nguyen+, 2012)
J/AJ/143/93 : Rotational velocities in early-M stars (Reiners+, 2012)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/ApJ/786/97 : Photospheric properties of T Tauri stars (Herczeg+, 2014)
J/MNRAS/468/931 : Orion Nebula Cluster members VRI photometry (Messina+, 2017)
J/MNRAS/480/3739 : Extended main sequence turnoff in open cl. (Bastian+, 2018)
J/AJ/155/225 : M dwarf stars rot. broadening measurements (Kesseli+, 2018)
J/AJ/156/271 : The stellar membership of the Taurus SFR (Luhman, 2018)
J/A+A/615/A76 : Spectroscopic param. of stars (SPECIES). I. (Soto+, 2018)
J/AJ/156/275 : Rot. evolution of young, binary M dwarfs (Stauffer+, 2018)
J/AJ/158/54 : New Taurus members (Esplin+, 2019)
J/ApJ/879/105 : Eff. temperatures of low-mass stars (Lopez-Valdivia+, 2019)
J/AJ/159/273 : Taurus members & nonmembers with K2 data (Rebull+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Name Target name (1)
21 A1 --- n_Name Flag on name (2)
23- 24 I2 h RAh [4/5] Hour of Right Ascension (J2000)
26- 27 I2 min RAm Minute of Right Ascension (J2000)
29- 30 I2 s RAs Second of Right Ascension (J2000)
32- 32 A1 --- DE- Sign of the Declination (J2000)
33- 34 I2 deg DEd [14/30] Degree of Declination (J2000)
36- 37 I2 arcmin DEm Arcminute of Declination (J2000)
39- 40 I2 arcsec DEs Arcsecond of Declination (J2000)
42- 46 F5.2 --- Kmag [5.3/11.6]? K-band apparent magnitude
48- 49 I2 --- Nir [3/54] Number of infrared observations
51- 52 I2 --- Nop [1/43]? Number of optical observations
54- 54 A1 --- Mult Multiplicity (3)
56- 59 I4 K Teff [3100/4900]? Effective temperature (4)
61- 61 A1 --- l_vsiniIR Limit flag on vsini-IR
63- 66 F4.1 km/s vsiniIR [4/50]? Infrared vsini (5)
68- 70 F3.1 km/s e_vsiniIR [1.7/3.4]? Infrared vsini uncertainty
72- 72 A1 --- l_vsiniOp Limit flag on vsini-op
74- 77 F4.1 km/s vsiniOp [7/50]? Optical vsini
79- 81 F3.1 km/s e_vsiniOp [0.4/5.1]? Optical vsini uncertainty
83- 87 F5.2 km/s vsini [4/83]? Published vsini (6)
89- 92 F4.2 km/s e_vsini [0.04/4]? Published vsini uncertainty
94- 98 F5.2 d Prot [0.7/15.7]? Stellar rotation period
100-103 F4.2 d e_Prot [0.02/0.1]? Period uncertainty
105-105 I1 --- r_Prot [1/8]? Period reference (7)
107-107 A1 --- l_Rsini Limit flag on Rsini
109-112 F4.2 Rsun Rsini [0.7/2.1]? Lower limit stellar radius
114-117 F4.2 Rsun e_Rsini [0.05/0.5]? Rsini uncertainty
119-119 A1 --- Class ? Classification (8)
121-121 I1 --- r_Class [1/4]? Classification reference (9)
--------------------------------------------------------------------------------
Note (1): In the cases where the target name represents a wide binary, only
the primary component was characterized unless the secondary is also
specified
Note (2): Flag as follows:
o = the targets belong to an older population with age >10Myr;
see Luhman 2018, J/AJ/156/271
Note (3): Code as follows:
S = single (38 occurrences),
B = binary (29 occurrences),
T = tertiary (2 occurrences),
Q = quadruple (1 occurrence).
Note (4): The relations used to determine Teff are limited to values between
3100-4100. Values outside this range are extrapolated.
All Teff uncertainties are 200K
Note (5): IT Tau and LkHa 332/G1 show evidence of possible contamination
from a stellar companion, which may lead to an overestimated vsini
Note (6): See Nguyen et al. (2012ApJ...745..119N 2012ApJ...745..119N)
Note (7): The stellar rotation periods were obtained from the following:
1 = Lowell Observatory photometry;
2 = K2 data;
3 = Bouvier et al. (1995A&A...299...89B 1995A&A...299...89B);
4 = Artemenko et al. (2012AstL...38..783A 2012AstL...38..783A);
5 = Grankin et al. (2008A&A...479..827G 2008A&A...479..827G);
6 = Norton et al. (2007A&A...467..785N 2007A&A...467..785N);
7 = Donati et al. (2019MNRAS.483L...1D 2019MNRAS.483L...1D);
8 = Percy et al. (2006PASP..118.1390P 2006PASP..118.1390P).
Note (8): Classification as follows:
C = classical T Tauri star (39 occurrences);
W = weak-line T Tauri star (24 occurrences)
Note (9): The target classification references are as follows:
1 = Herbig & Bell (1988cels.book.....H 1988cels.book.....H);
2 = Kraus et al. (and references therein) (2012ApJ...745...19K 2012ApJ...745...19K);
3 = Nguyen et al. (2012ApJ...745..119N 2012ApJ...745..119N);
4 = Chavarria-K et al. (2000A&AS..145..187C 2000A&AS..145..187C).
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Oct-2022