J/AJ/159/273 Taurus members & nonmembers with K2 data (Rebull+, 2020)
Rotation of low-mass stars in Taurus with K2.
Rebull L.M., Stauffer J.R., Cody A.M., Hillenbrand L.A., Bouvier J.,
Roggero N., David T.J.
<Astron. J., 159, 273 (2020)>
=2020AJ....159..273R 2020AJ....159..273R
ADC_Keywords: Molecular clouds; YSOs; Stars, variable; Photometry, infrared;
Optical; Colors
Keywords: Star formation ; Stellar rotation ; Starspots
Abstract:
We present an analysis of K2 light curves (LCs) from Campaigns 4 and
13 for members of the young (∼3Myr) Taurus association, in addition to
an older (∼30Myr) population of stars that is largely in the
foreground of the Taurus molecular clouds. Out of 156 of the
highest-confidence Taurus members, we find that 81% are periodic. Our
sample of young foreground stars is biased and incomplete, but nearly
all stars (37/38) are periodic. The overall distribution of rotation
rates as a function of color (a proxy for mass) is similar to that
found in other clusters: the slowest rotators are among the early M
spectral types, with faster rotation toward both earlier FGK and later
M types. The relationship between period and color/mass exhibited by
older clusters such as the Pleiades is already in place by Taurus age.
The foreground population has very few stars but is consistent with
the USco and Pleiades period distributions. As found in other young
clusters, stars with disks rotate on average slower, and few with
disks are found rotating faster than ∼2days. The overall amplitude of
the LCs decreases with age, and higher-mass stars have generally lower
amplitudes than lower-mass stars. Stars with disks have on average
larger amplitudes than stars without disks, though the physical
mechanisms driving the variability and the resulting LC morphologies
are also different between these two classes.
Description:
Stars in the Taurus Molecular Cloud (TMC) were observed in two
different K2 campaigns: Campaign 4 (C4; 2015-February-7 to
2015-April-24) and Campaign 13 (C13; 2017-March-8 to 2017-May-27), see
Howell+, 2014PASP..126..398H 2014PASP..126..398H.
There are ∼850 candidate Taurus members with K2 light curves (LCs)
from either campaign. All of the LCs used here were observed in the
long-cadence (∼30minutes cadence) mode.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 230 217 Periods and supporting data for Taurus members with
K2 light curves
tablea1.dat 209 632 Periods and supporting data for Taurus likely
nonmembers with K2 light curves
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See also:
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
II/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)
J/ApJS/101/117 : UBVRIJHKLMNQ photometry in Taurus-Auriga (Kenyon+ 1995)
J/A+A/312/439 : New T Tauri stars in Taurus-Auriga (Wichmann+, 1996)
J/A+AS/125/229 : A standard stellar library (Lejeune+ 1997)
J/A+A/349/619 : UBVRI light curves of AA Tau in 1995 (Bouvier+, 1999)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
J/A+A/409/169 : UBVRI light curves of AA Tau in 1999 (Bouvier+, 2003)
J/AJ/131/3016 : Low-mass objects in Upper Scorpius (Slesnick+, 2006)
J/A+A/463/1017 : B and V light curves of AA Tau (Bouvier+, 2007)
J/A+A/468/353 : XMM-Newton Extended Survey of Taurus (Guedel+, 2007)
J/ApJ/704/531 : The coevality of young binary systems (Kraus+, 2009)
J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)
J/ApJS/196/4 : New young star candidates in Taurus-Auriga (Rebull+, 2011)
J/A+A/557/A77 : VR light curves of AA Tau in 2007-2013 (Bouvier+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/AJ/147/82 : Monitoring of disk-bearing stars in NGC 2264 (Cody+, 2014)
J/AJ/152/114 : Pleiades members with K2 light curves. II. (Rebull+, 2016)
J/AJ/152/113 : Pleiades members with K2 light curves. I. (Rebull+, 2016)
J/AJ/152/142 : Spitzer and WISE light curves of Neptune (Stauffer+, 2016)
J/AJ/154/134 : Planetary-mass brown dwarfs in the Taurus SFR (Esplin+, 2017)
J/ApJ/838/150 : The Taurus-Auriga ecosystem. I. (Kraus+, 2017)
J/AJ/153/46 : Spectroscopy of candidate members in Taurus (Luhman+, 2017)
J/AJ/153/257 : Comoving stars in Gaia DR1 (Oh+, 2017)
J/ApJ/839/92 : Praesepe members with K2 light curve data (Rebull+, 2017)
J/ApJ/848/97 : Young stellar variables with KELT for K2. I. (Rodriguez+,2017)
J/AJ/156/71 : K2 Campaign2: young disk-bearing stars Sco & Oph (Cody+, 2018)
J/AJ/156/271 : The stellar membership of the Taurus SFR (Luhman, 2018)
J/AJ/155/196 : Analysis K2 LCs for members of USco & ρOph (Rebull+ 2018)
J/AJ/156/275 : Rotational evolut. of young, binary M dwarfs (Stauffer+, 2018)
J/AJ/158/54 : New Taurus members, stellar to planetary masses (Esplin+,2019)
J/A+A/630/A137 : Structure and kinematics of the Taurus region (Galli+, 2019)
J/AJ/159/105 : 2 new stellar associations in vicinity of the Sun (Liu+, 2020)
J/AJ/159/15 : Binary stars in Upper Scorpius (Tokovinin+, 2020)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- EPIC [210509151/248180268] EPIC identifier
11- 12 I2 h RAh [04/05] Hour of right ascension (J2000)
13- 14 I2 min RAm Minute of right ascension (J2000)
15- 19 F5.2 s RAs Second of right ascension (J2000)
20 A1 --- DE- [+] Sign of declination (J2000)
21- 22 I2 deg DEd [14/27] Degree of declination (J2000)
23- 24 I2 arcmin DEm Arcminute of declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of declination (J2000)
30- 52 A23 --- OName Other target identifier
54- 72 A19 --- Gaia Gaia DR2 identifier
74- 78 F5.2 mag Vmag [6.92/24.92]? Apparent V band Vega magnitude
80- 84 F5.2 mag Ksmag [5.32/15.44] Apparent Ks band Vega magnitude
86- 90 F5.2 mag (V-Ks)o [0.08/11.58]? Observed (V-Ks) color
92- 96 F5.2 mag (V-Ks)u [0.08/15.74] Used (V-Ks) color (1)
98-102 F5.2 mag E(V-Ks) [0/14.3] Adopted (V-Ks) color excess (2)
104-108 F5.2 mag Ksmag0 [4.15/15.37] Inferred dereddended Ks Vega
magnitude (2)
110-114 F5.2 mag (V-Ks)0 [-0.48/9.8] Inferred dereddended (V-Ks) color (3)
116 I1 --- r_mag References for magnitudes (G1)
118 I1 --- f_E(V-Ks) Origin of E(V-Ks) leading to (V-Ks)0 (G2)
120-126 F7.4 d P1 [0.18/28]? Primary period (4)
128-134 F7.4 d P2 [0.05/16]? Secondary period
136-142 F7.4 d P3 [0.31/12]? Tertiary period
144-149 F6.4 d P4 [0.18/0.27]? Quaternary period
151-161 A11 --- Member Membership classification (5)
163-167 A5 --- IRexcess Presence of an IR excess
169-172 A4 um IRexStr Minimum wavelength where IR excess is detected
(6)
174-178 F5.2 --- Slope [-2.89/1.94]? SED slope (7)
180-183 A4 --- Class SED class; I, flat, II, or III
185-187 A3 --- dip LC matches dipper characteristics (8)
189-191 A3 --- burst LC matches burster characteristics (8)
193-198 A6 --- mult Single or multi-period star flag
200-202 A3 --- dd LC and power spectrum matches double-dip
characteristics (8)
204-206 A3 --- ddmove LC and power spectrum matche moving double-dip
characteristics (8)
208-210 A3 --- shape LC matches shape changer characteristics (8)
212-214 A3 --- beat LC has beating visible (8)
216-218 A3 --- complex Power spectrum has a complex, structured peak
and/or wide peak (8)
220-222 A3 --- closep Power spectrum has resolved close peaks (8)
224-226 A3 --- distp Power spectrum has resolved distant peaks (8)
228-230 A3 --- pulse Power spectrum and LC match pulsator
characteristics (8)
--------------------------------------------------------------------------------
Note (1): Observed or inferred; see text.
Note (2): In order to deredden the (V-Ks) colors, we followed the same
approach as in Rebull+, 2018, J/AJ/155/196, with some modifications
explained at section 2.5 in the article.
Note (3): Rounded to nearest 0.1 to emphasize the relatively low accuracy.
Note (4): Taken to be rotation period in cases where there is >1 period.
Note (5): Highest quality member, possible member, foreground young star
(see section 2.2).
Note (6): Or the limit of our knowledge of where there is no excess
(see section 4).
Note (7): Fit to all available detections between 2 and 25µm
Note (8): In Papers II (Rebull+, 2016, J/AJ/152/113), IV (Rebull+,
2017, J/ApJ/839/92) and V (Rebull+, 2018, J/AJ/155/196) we classified
the Light Curves (LC) and periodogram morphologies for the Pleiades,
Praesepe, USco, and pOph; see these references for discussion of the
classes (e.g., double-dip, scallop, etc.). See section 6.2 for more
informations.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- EPIC EPIC identifier
11- 12 I2 h RAh [03/05] Hour of right ascension (J2000)
13- 14 I2 min RAm Minute of right ascension (J2000)
15- 19 F5.2 s RAs Second of right ascension (J2000)
20 A1 --- DE- [+] Sign of declination (J2000)
21- 22 I2 deg DEd [12/28] Degreee of declination (J2000)
23- 24 I2 arcmin DEm Arcminute of declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of declination (J2000)
30- 54 A25 --- OName Other target identifier
56- 74 A19 --- Gaia Gaia DR2 identifier
76- 80 F5.2 mag Vmag [4.82/22.5]? Apparent V band Vega magnitude
82- 86 F5.2 mag Ksmag [3.02/16.4] Apparent Ks band Vega magnitude
88- 92 F5.2 mag (V-Ks)o [-0.29/8.71]? Observed (V-Ks) color
94- 98 F5.2 mag (V-Ks)u [-0.29/14.1] Used (V-Ks) color (1)
100-104 F5.2 mag E(V-Ks) [0/10.2] Adopted (V-Ks) color excess (2)
106-110 F5.2 mag Ksmag0 [2.6/16.4] Inferred dereddended Ks Vega magnitude
(2)
112-116 F5.2 mag (V-Ks)0 [-0.87/13.7] Inferred dereddended (V-Ks) color
(3)
118 I1 --- r_mag References for magnitudes (G1)
120 I1 --- f_E(V-Ks) Origin of E(V-Ks) leading to (V-Ks)0 (G2)
122-128 F7.4 d P1 [0.04/25.4]? Primary period (4)
130-135 F6.4 d P2 [0.05/8.86]? Secondary period
137-142 F6.4 d P3 [0.04/9.21]? Tertiary period
144-149 F6.4 d P4 [0.05/2.39]? Quaternary period
151-155 A5 --- IRexcess Presence of an IR excess; see parargaph 4
157-159 A3 um IRexStr Minimum wavelength where IR excess is detected
(5)
161-165 F5.2 --- Slope [-4.04/1.06]? SED slope (6)
167-170 A4 --- Class SED class; I, flat, II, or III
172-177 A6 --- mult Single or multi-period star flag
179-181 A3 --- dd LC and power spectrum matches double-dip
characteristics (7)
183-185 A3 --- ddmove LC and power spectrum matche moving double-dip
characteristics (7)
187-189 A3 --- shape LC matches shape changer characteristics (7)
191-193 A3 --- beat LC has beating visible (7)
195-197 A3 --- complex Power spectrum has a complex, structured peak
and/or wide peak (7)
199-201 A3 --- closep Power spectrum has resolved close peaks (7)
203-205 A3 --- distp Power spectrum has resolved distant peaks (7)
207-209 A3 --- pulse Power spectrum and LC match pulsator
characteristics (7)
--------------------------------------------------------------------------------
Note (1): Observed or inferred; see text.
Note (2): In order to deredden the (V-Ks) colors, we followed the same
approach as in Rebull+, 2018, J/AJ/155/196, with some modifications
explained at section 2.5 in the article.
Note (3): Rounded to nearest 0.1 to emphasize the relatively low accuracy.
Note (4): Taken to be rotation period in cases where there is >1 period.
Note (5): Or the limit of our knowledge of where there is no excess
(see section 4).
Note (6): Fit to all available detections between 2 and 25µm.
Note (7): In Papers II (Rebull+, 2016, J/AJ/152/113), IV (Rebull+,
2017, J/ApJ/839/92) and V (Rebull+, 2018, J/AJ/155/196) we classified
the Light Curves (LC) and periodogram morphologies for the Pleiades,
Praesepe, USco, and pOph; see these references for discussion of the
classes (e.g., double-dip, scallop, etc.). See section 6.2 for more
informations.
--------------------------------------------------------------------------------
Global Notes:
Note (G1): Code as follows:
1 = V measured directly from the literature (including SIMBAD)
and Ks from 2MASS
2 = V from APASS and Ks from 2MASS
3 = (V-Ks)o inferred from Gaia g and Ks from 2MASS
4 = (V-Ks)o inferred from Pan-STARRS1 g and Ks from 2MASS
6 = V inferred from well-populated optical SED and Ks from 2MASS
See section 2.3 in the article for more details.
Note (G2): Code as follows:
1 = dereddening from JHKs diagram
2 = dereddening back to (V-Ks)0 expected for spectral type
3 = used median E(V-Ks)=0.7
4 = no measure of E(V-Ks)
See section 2.5 in the article for more details.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Rebull et al Paper I. 2016AJ....152..114R 2016AJ....152..114R cat. J/AJ/152/114
Rebull et al. Paper II. 2016AJ....152..113R 2016AJ....152..113R cat. J/AJ/152/113
Stauffer et al. Paper III. 2016AJ....152..142S 2016AJ....152..142S cat. J/AJ/152/142
Rebull et al. Paper IV. 2017ApJ...839...92R 2017ApJ...839...92R cat. J/ApJ/839/92
Rebull et al. Paper V. 2018AJ....155..196R 2018AJ....155..196R cat. J/AJ/155/196
(End) Prepared by [AAS], Coralie Fix [CDS], 28-Aug-2020