J/ApJS/257/45 BDKP. V. Radial & rot. velocities of M, L, T dwarfs (Hsu+, 2021)
The Brown Dwarf Kinematics Project (BDKP).
V. Radial and rotational velocities of T dwarfs from Keck/NIRSPEC
high-resolution spectroscopy.
Hsu C.-C., Burgasser A.J., Theissen C.A., Gelino C.R., Birky J.L.,
Diamant S.J.M., Bardalez Gagliuffi D.C., Aganze C., Blake C.H., Faherty J.K.
<Astrophys. J. Suppl. Ser., 257, 45 (2021)>
=2021ApJS..257...45H 2021ApJS..257...45H
ADC_Keywords: Stars, brown dwarf; Radial velocities; Rotational velocities;
Spectra, infrared; Space velocities ; Stars, T-type
Keywords: Brown dwarfs ; T dwarfs ; Radial velocity ; Stellar kinematics ;
Stellar dynamics
Abstract:
We report multiepoch radial velocities, rotational velocities, and
atmospheric parameters for 37 T-type brown dwarfs observed with
Keck/NIRSPEC. Using a Markov Chain Monte Carlo forward-modeling
method, we achieve median precisions of 0.5 and 0.9km/s for radial and
rotational velocities, respectively. All of the T dwarfs in our sample
are thin-disk brown dwarfs. We confirm previously reported moving
group associations for four T dwarfs. However, the lack of spectral
indicators of youth in two of these sources suggests that these are
chance alignments. We confirm two previously unresolved binary
candidates, the T0+T4.5 2MASS J11061197+2754225 and the L7+T3.5
2MASSJ21265916+7617440, with orbital periods of 4 and 12yr,
respectively. We find a kinematic age of 3.5±0.3Gyr for local
T dwarfs, consistent with nearby late M dwarfs (4.1±0.3Gyr). Removal
of thick-disk L dwarfs in the local ultracool dwarf sample gives a
similar age for L dwarfs (4.2±0.3Gyr), largely resolving the local
L dwarf age anomaly. The kinematic ages of local late M, L, and T
dwarfs can be accurately reproduced with population simulations
incorporating standard assumptions of the mass function, star
formation rate, and brown dwarf evolutionary models. A kinematic
dispersion break is found at the L4-L6 subtypes, likely reflecting the
terminus of the stellar main sequence. We provide a compilation of
precise radial velocities for 172 late M, L, and T dwarfs within ∼20pc
of the Sun.
Description:
Our T dwarf sample was compiled from sources observed with the Keck
Near-Infrared Spectrometer (NIRSPEC). NIRSPEC is a high-resolution,
near-infrared, cross-dispersed spectrograph, mounted on the Keck II
telescope, spanning 0.95-5.5um with a spectral resolution of ∼25000
(pre-upgrade) and ∼35000 (post-upgrade) for a slit width of 0.432"
(see Table 1). Our sample encompasses observations taken between 2000
and 2021, including publicly available archival data obtained from the
Keck Observatory Archive (KOA).
To place the T dwarf velocity dispersions and kinematic ages in
context, we compiled all late M and L dwarfs within 20pc with
published RV measurements that have uncertainties of ≤3km/s, based on
medium- and high-resolution spectroscopic measurements (see Table 7).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 141 37 NIRSPEC T dwarf sample
table2.dat 90 102 NIRSPEC T dwarf observing log
table4.dat 189 94 Spectral model fit parameters
table5.dat 76 37 Radial velocities and heliocentric space motions
of the T dwarf sample
table7.dat 146 136 Late-M and L dwarf sample at the local 20pc
table8.dat 90 136 Radial velocities and heliocentric space motions of
late M and L dwarfs within 20pc of the Sun
tableb1.dat 70 584 Simulated UCD population ages under different
assumptions
refs.dat 71 116 References
--------------------------------------------------------------------------------
See also:
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/363/1081 : Non-linear limb-darkening law for LTE models (Claret 2000)
J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/A+A/410/527 : Abundances in the Galactic disk (Bensby+, 2003)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/AJ/126/3007 : Spectroscopy of faint red NLTT dwarfs (Reid+, 2003)
J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004)
J/AJ/127/3553 : JHK phot. and spectroscopy for L and T dwarfs (Knapp+, 2004)
J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)
J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)
J/A+A/440/1061 : Southern red high proper motion objects (Lodieu+, 2005)
J/PASP/117/676 : LHS faint proper-motion stars (Reid+, 2005)
J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)
J/AJ/132/891 : Binaries among nearby L dwarfs (Reid+, 2006)
J/AJ/134/1162 : 11 new T dwarfs in 2MASS (Looper+, 2007)
J/AJ/133/2258 : Kinematics of ultracool dwarfs (Schmidt+, 2007)
J/MNRAS/384/1399 : Proper motions of field L and T dwarfs (Jameson+, 2008)
J/ApJ/676/1281 : L and T dwarfs in 2MASS/SDSS (Metchev+, 2008)
J/MNRAS/383/831 : New DENIS nearby L and late-M dwarfs (Phan-Bao+, 2008)
J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)
J/A+A/501/1059 : Infrared spectra of 9 T dwarfs (del Burgo+, 2009)
J/AJ/137/1 : PMs and astrometry of late-type dwarfs (Faherty+, 2009)
J/ApJ/705/1416 : Volume-limited sample of M7-M9.5 dwarfs (Reiners+, 2009)
J/ApJ/723/684 : NIRSPEC ultracool dwarf RVel survey (Blake+, 2010)
J/ApJ/710/1142 : SpeX spectrosc. of low mass binaries. I. (Burgasser+, 2010)
J/ApJS/190/100 : NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)
J/ApJ/710/1627 : Mid-IR photometry of cold brown dwarfs (Leggett+, 2010)
J/MNRAS/407/2269 : Polarisation of a sample of late M dwarfs (Morin+, 2010)
J/AJ/139/1808 : Colors and kinematics of SDSS L dwarfs (Schmidt+, 2010)
J/A+A/512/A37 : Velocities of 43 nearby L dwarfs (Seifahrt+, 2010)
J/AJ/142/77 : New T dwarfs identified in Pan-STARRS 1 (Deacon+, 2011)
J/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)
J/AJ/141/97 : SDSS DR7 M dwarfs (West+, 2011)
J/AJ/144/99 : Near-IR spectroscopy of 36 late M dwarfs (Deshpande+, 2012)
J/ApJS/201/19 : Hawaii Infrared Parallax Program. I. (Dupuy+, 2012)
J/ApJ/752/56 : BDKP. III. Plxs for 70 ultracool dwarfs (Faherty+, 2012)
J/ApJ/758/56 : Young M dwarfs within 25pc. II. Kinematics (Shkolnik+, 2012)
J/AJ/146/156 : APOGEE M-dwarf survey. I. 1st-yr vel. (Deshpande+, 2013)
J/MNRAS/428/2824 : Rapid optical variability in ultracool dwarfs (Koen, 2013)
J/ApJS/205/6 : T dwarf population revealed by WISE (Mace+, 2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/PASP/125/809 : New nearby M, L, and T dwarfs (Thompson+, 2013)
J/ApJ/794/143 : New SpeX Observations of M7-L6 Dwarfs (Bardalez+, 2014)
J/A+A/566/A130 : Rot. & variability of substellar objects (Crossfield, 2014)
J/AJ/147/94 : Solar neighborhood. XXXII. L and M dwarfs (Dieterich+, 2014)
J/ApJ/784/156 : Plxs for 1507 nearby mid-to-late M dwarfs (Dittmann+, 2014)
J/A+A/568/A9 : 300-2500nm flux calibration ref. spectra (Moehler+, 2014)
J/AJ/147/20 : Spectroscopy of 447 nearby M dwarfs (Newton+, 2014)
J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)
J/AJ/147/34 : SpeX library of L-type dwarfs (Schneider+, 2014)
J/A+A/566/A111 : Brown dwarf atmosphere monitoring (BAM) (Wilson+, 2014)
J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)
J/ApJS/220/18 : BDKP IV. RVs of M & L dwarfs with MagE (Burgasser+, 2015)
J/ApJ/810/158 : M,L,T dwarfs fundamental param. and SEDs (Filippazzo+, 2015)
J/ApJS/219/33 : BANYAN. VII. Candidate YMG members from BASS (Gagne+, 2015)
J/other/Sci/350.64 : 51 Eri b near-infrared spectrum (Macintosh+, 2015)
J/ApJS/220/16 : SpeX NIR survey of 886 nearby M dwarfs (Terrien+, 2015)
J/ApJ/812/3 : MEarth mid-to-late M dwarfs rot. & kinematics (West+, 2015)
J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)
J/ApJS/224/36 : The AllWISE motion survey (AllWISE2) (Kirkpatrick+, 2016)
J/ApJ/817/112 : NEOWISE/AllWISE high PM objects (Schneider+, 2016)
J/AJ/152/24 : Trigonometric plxs of 134 low-mass stars (Weinberger+, 2016)
J/AJ/154/147 : Astrometry for late-type dwarfs & subdwarfs (Dahn+, 2017)
J/ApJS/231/15 : Astrometry of ultracool dwarf binaries (Dupuy+, 2017)
J/MNRAS/465/4723 : Log of SALT-RSS observations (Koen+, 2017)
J/ApJ/838/73 : BD surface gravities with Keck/NIRSPEC (Martin , 2017)
J/A+A/603/A57 : 51 Eri b SPHERE/IFS sp. & atmosphere models (Samland+, 2017)
J/ApJS/234/1 : M, L, & T dwarfs from PS1 3π Survey (Best+, 2018)
J/ApJ/856/23 : BANYAN. XI. The BANYAN Σ algorithm (Gagne+, 2018)
J/AJ/156/217 : Stellar data for M dwarfs in MEarth-South (Newton+, 2018)
J/A+A/619/L8 : Ultra-cool dwarfs candidates in Gaia DR2 (Reyle, 2018)
J/ApJ/858/L7 : Red clump stars selected from LAMOST & APOGEE (Ting+, 2018)
J/AJ/157/231 : MLSDSS-GaiaDR2 sample of M and L dwarfs (Kiman+, 2019)
J/ApJS/240/19 : Parallaxes of late-T and Y dwarfs (Kirkpatrick+, 2019)
J/AJ/157/101 : Cloud Atlas: HST/WFC3 NIR sp. library (Manjavacas+, 2019)
J/ApJ/878/21 : Vertical motions of APOGEE & Gaia RC stars (Ting+, 2019)
J/AJ/159/257 : Hawaii IR plx prog. IV. L0-T8 BDs with UKIRT (Best+, 2020)
J/ApJ/899/123 : Spitzer follow up of 95 brown dwarfs (Meisner+, 2020)
J/AJ/160/63 : IR sp. of 5 BDs with Gemini North IRS (Miles+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Identifier of the star (JHHMM+DDMM)
12 A1 --- f_ID Flag on ID (1)
14- 15 I2 h RAh Hour of right ascension (J2000)
17- 18 I2 min RAm Minute of right ascension (J2000)
20- 24 F5.2 s RAs Second of right ascension (J2000)
26 A1 --- DE- Sign of declination (J2000)
27- 28 I2 deg DEd Degree of declination (J2000)
30- 31 I2 arcmin DEm Arcminute of declination (J2000)
33- 36 F4.1 arcsec DEs Arcsecond of declination (J2000)
38- 46 A9 --- SpTl Spectral type
48 A1 --- f_SpTl Flag on SpTl (1)
50- 55 F6.3 mag Jmag [13.46/16.11] 2MASS J-band magnitude
57- 61 F5.3 mag e_Jmag [0.004/0.5] Uncertainty on the Jmag
63- 68 F6.3 mag J-K [-0.94/1.63] J-K color index
70- 73 F4.2 mag e_J-K [0.03/0.5] J-K uncertainty
75- 79 I5 mas/yr pmRA [-1194/2214] Proper motion in right ascension
81- 82 I2 mas/yr e_pmRA [0/65] pmRA uncertainty
84- 88 I5 mas/yr pmDE [-1726/1042] Proper motion in declination
90 I1 mas/yr e_pmDE [0/5] pmDE uncertainty
92- 96 F5.2 pc Dist [5.16/26.7] Distance
98- 101 F4.2 pc e_Dist [0.01/2.4] Dist uncertainty
103- 107 F5.1 km/s RVl [-40.5/49.6]? Radial velocity
109- 111 F3.1 km/s e_RVl [0.4/3]? RVl uncertainty
113 A1 --- l_vsini Limit flag on vsini
115- 118 F4.1 km/s vsini [11.5/60]? Rotational velocity
120- 123 F4.1 km/s e_vsini [0.8/10]? vsini uncertainty
125- 141 A17 --- Ref Discovery/classification references
(see refs.dat file)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = References are in the order of discovery, classification,
astrometry, previously published RV, and vsini measurements.
b = Previously identified as a member of the Carina-Near moving group.
c = Suspected binary based on blended-light spectrum; the component types
are estimated to be L7+T5.5 for J0629+2418 (Mace+ 2013, J/ApJS/205/6)
and T1.5+T2.5 for J0909+6525 (Burgasser+ 2010, J/ApJ/710/1142).
d = Confirmed binary as reported in Burgasser+ (2003ApJ...586..512B 2003ApJ...586..512B ;
2006ApJS..166..585B 2006ApJS..166..585B and 2010, J/ApJ/710/1142),
Kirkpatrick+ (2010, J/ApJS/190/100), Dupuy & Liu (2012, J/ApJS/201/19),
and this paper.
e = Previously identified as a member of the AB Doradus moving group.
f = Distance is estimated using the MJ/spectral type relation in
Dupuy & Liu (2012, J/ApJS/201/19).
g = T0 spectral type from Schneider+, J/AJ/147/34 -- determined as a blue
L6 in this work; see Section 4.4 and Figure 15 for details.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Identifier of the star (JHHMM+DDMM) (1)
12 A1 --- f_ID d=Observed with the upgraded NIRSPEC
14- 24 A11 --- PID Observation program identifier
26- 35 A10 "Y/M/D" Obs.date UT date of the observation
37- 44 A8 "h:m:s" Obs.time Time of the observation (2)
46- 53 A8 s Exp Integration time (3)
55- 58 F4.2 --- AirMass [1/2.38] Air mass (2)
60- 61 A2 --- Filt Filter (4)
63- 70 A8 arcsec Slit Slit
72- 76 F5.2 deg EchA [62.61/63.03] Echelle angle (2)
78- 82 F5.2 deg CDA [34.06/36.9] Cross-disperser angle (2)
84- 90 F7.3 km/s Corr [-29.26/30.294] Barycentric correction
--------------------------------------------------------------------------------
Note (1): J1553+1523 is a misprint for J1553+1532; corrected at CDS.
Note (2): Values are taken from the configuration of the first file within
the same night.
Note (3): The number of files times the individual integration time.
Note (4): Filters: N3 (NIRSPEC-3; J-band), N5 (NIRSPEC-5),
N7 (NIRSPEC-7; K-band) and K (NIRSPEC K).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Identifier of the star (JHHMM+DDMM) (1)
12- 12 A1 --- Flag [hi] Flag on adopted Teff/logg (2)
14- 22 A9 --- SpT Spectral Type
24- 34 A11 "Y/M/D" Date UT date of observation
36- 36 A1 --- f_Date [g] Flag on observation date (2)
38- 39 I2 --- Order [33/58] Spectral order of data
41- 41 A1 --- f_Order [fj] flag on Order (2)
43- 44 I2 --- SN [1/78]? Signal to noise ratio
46- 50 F5.1 km/s RV [-43.4/56.2]? Individual radial velocity
at Obs
52- 54 F3.1 km/s E_RV [0.2/5.3]? Upper uncertainty in RV
56- 58 F3.1 km/s e_RV [0.2/4.1]? Lower uncertainty in RV
60- 63 F4.1 km/s vsini [4.4/89.6]? Individual vsin(i) at Obs
65- 68 F4.1 km/s E_vsini [0.5/10.3]? Upper uncertainty in vsini
70- 72 F3.1 km/s e_vsini [0.4/9]? Lower uncertainty in vsini
74- 78 F5.1 km/s RV-m [-43.4/56.2]? Weighted average of RV
over all epochs
80- 82 F3.1 km/s E_RV-m [0.1/2.7]? Upper uncertainty in RV-m
84- 86 F3.1 km/s e_RV-m [0.1/2.1]? Lower uncertainty in RV-m
88- 92 F5.1 km/s RV-l [-40.5/49.6]? Literature RV
94- 96 F3.1 km/s e_RV-l [0.4/3.0]? Uncertainty in RV-l
98- 98 A1 --- l_vsini-m Limit flag on vsini-m
100-103 F4.1 km/s vsini-m [9/89.6]? Weighted average of vsini
over all epochs
105-108 F4.1 km/s E_vsini-m [0.3/10]? Upper uncertainty in vsini-m
110-112 F3.1 km/s e_vsini-m [0.2/9]? Lower uncertainty in vsini-m
114-114 A1 --- f_vsini-m [k] flag on vsini-m (2)
115-115 A1 --- l_vsini-l [<] Limit flag on vsini-l
116-119 F4.1 km/s vsini-l [11.5/60]? Literature vsini
121-124 F4.1 km/s e_vsini-l [0.8/10]? Uncertainty in vsini-l
126-129 I4 K Teff [744/1700]? Individual measured
effective temperature
131-133 I3 K E_Teff [1/104]? Upper uncertainty in Teff
135-137 I3 K e_Teff [2/156]? Lower uncertainty in Teff
139-142 I4 K Teff-m [744/1698]? Weighted average of Teff
over all epochs
144-145 I2 K E_Teff-m [1/97]? Upper uncertainty in Teff-m
147-148 I2 K e_Teff-m [1/46]? Lower uncertainty in Teff-m
150-153 F4.2 [cm/s2] logg [4.2/5.5]? Individual measured surface
gravity
155-159 F5.3 [cm/s2] E_logg [0/0.7]? Upper uncertainty in logg
161-165 F5.3 [cm/s2] e_logg [0/0.7]? Lower uncertainty in logg
167-171 F5.3 [cm/s2] logg-m [4.5/5.5]? Weighted average of logg
over all epochs
173-177 F5.3 [cm/s2] E_logg-m [0.001/0.5]? Upper uncertainty in logg-m
179-183 F5.3 [cm/s2] e_logg-m [0.001/0.4]? Lower uncertainty in logg-m
185-185 A1 --- Model [BS] Models used (3)
187-189 A3 --- Ref References (4)
--------------------------------------------------------------------------------
Note (1): J1553+1523 is a misprint for J1553+1532; corrected at CDS.
Note (2): Flag as follows:
h = Adopted Teff and logg are determined using order 33 measurements only;
see Section 3.4.3;
i = Adopted Teff and logg are determined using order 58 measurements only;
see Section 3.4.3.
g = Measurements are considered unreliable due to low S/N.
f = No telluric observations available for this epoch.
k = The vsini detection floor for NIRSPEC is 9km/s for S/N≥5,
and 15km/s for S/N<5 data; see Section 3.3.4.
Note (3): Models used as follows:
S = Sonora 2018 (Marley+ doi:10.5281/zenodo.2628068);
B = BT-Settl (Allard+ 2012EAS....57....3A 2012EAS....57....3A).
Note (4): References as follows:
1 = Zapatero Osorio+ (2006ApJ...647.1405Z 2006ApJ...647.1405Z);
2 = Zapatero Osorio+ (2007ApJ...666.1205Z 2007ApJ...666.1205Z);
3 = Prato+ (2015ApJ...808...12P 2015ApJ...808...12P);
4 = Gagne+ (2017ApJ...841L...1G 2017ApJ...841L...1G);
5 = Gagne+ (2018ApJ...854L..27G 2018ApJ...854L..27G).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Identifier of the star (JHHMM+DDMM)
12- 20 A9 --- SpT Spectral type
22 A1 --- n_SpT b=Known or candidate binary
24- 28 F5.1 km/s RV [-43.4/56.2] Adopted radial velocity
30- 32 F3.1 km/s e_RV [0.1/2.1] Lower uncertainty on RV
34- 36 F3.1 km/s E_RV [0.1/2.7] Upper uncertainty on RV
38- 42 F5.1 km/s UVel [-94.6/63.4] U space velocity
44- 46 F3.1 km/s e_UVel [0.1/5] UVel uncertainty
48- 52 F5.1 km/s VVel [-83.8/28.7] V space velocity
54- 56 F3.1 km/s e_VVel [0.1/9.7] VVel uncertainty
58- 62 F5.1 km/s WVel [-36.3/28] W space velocity
64- 66 F3.1 km/s e_WVel [0.1/4.1] WVel uncertainty
68- 71 F4.2 --- Prob [0.01/0.27] TD to D probability ratio
73- 76 A4 --- Pop Population (G1)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Star identifier (JHHMM+DDMMA)
13- 13 A1 --- f_Name Flags on Name (1)
15- 16 I2 h RAh Hour of Right Ascension (J2000)
18- 19 I2 min RAm Minute of Right Ascension (J2000)
21- 25 F5.2 s RAs Second of Right Ascension (J2000)
27- 27 A1 --- DE- Sign of the Declination (J2000)
28- 29 I2 deg DEd Degree of Declination (J2000)
31- 32 I2 arcmin DEm Arcminute of Declination (J2000)
34- 38 F5.2 arcsec DEs Arcsecond of Declination (J2000)
40- 51 A12 --- SpTl Spectral Type
53- 57 F5.2 mag Jmag [8.39/16.48]? 2MASS J-band magnitude
59- 62 F4.2 mag e_Jmag [0/0.5]? Uncertainty in Jmag
64- 67 F4.2 mag J-Ks [0.8/2.55]? 2MASS J-Ks color
69- 72 F4.2 mag e_J-Ks [0.01/0.71]? Uncertainty in J-Ks
74- 81 F8.2 mas/yr pmRA [-1856/3429.5]? Proper motion in Right Ascension
83- 87 F5.2 mas/yr e_pmRA [0.1/87]? Uncertainty in pmRA
89- 96 F8.2 mas/yr pmDE [-3806.2/1471]? Proper motion in Declination
98-102 F5.2 mas/yr e_pmDE [0.1/50]? Uncertainty in pmDE
104-109 F6.3 pc Dist [3.8/20]? Distance
111-115 F5.3 pc e_Dist [0.002/2]? Uncertainty in Dist
117-124 F8.3 km/s RV-l [-102.8/83.8]? Published Radial velocity
126-130 F5.3 km/s e_RV-l [0.009/3]? Uncertainty in RV-l
132-134 I3 --- r_SpTl [701/773]? Reference for SpT (see refs.dat file)
136-138 I3 --- r_pmRA [716/753]? Reference for pmRA/pmDE
(see refs.dat file)
140-142 I3 --- r_Dist [726/753]? Reference for Dist
(see refs.dat file)
144-146 I3 --- r_RV-l [720/772]? Reference for RV-l
(see refs.dat file)
--------------------------------------------------------------------------------
Note (1): Source flags as follows:
b = Identified as a member of the Argus moving group using BANYAN Σ
c = Identified as a member of the AB Doradus moving group using BANYAN Σ
d = Identified as a member of the Carina-Near moving group using BANYAN Σ
e = Suspected young source from Faherty+ (2016, J/ApJS/225/10)
f = Weird red L dwarf; also reported as L4pec in Faherty+ (2016, J/ApJS/225/10)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Star name (JHHMM+DDMMA)
13- 24 A12 --- SpT Spectral type
26 A1 --- f_SpT Flag on spectral type (1)
28- 35 F8.3 km/s RV [-102.8/83.8] Radial velocity
37- 41 F5.3 km/s e_RV [0.009/3] RV uncertainty
43- 48 F6.2 --- UVel [-92.2/65.3] U space velocity
50- 53 F4.2 --- e_UVel [0.03/7] UVel uncertainty
55- 61 F7.2 --- VVel [-122.5/53.8] V space velocity
63- 67 F5.2 --- e_VVel [0.02/13.5] VVel uncertainty
69- 74 F6.2 --- WVel [-51.64/78.6] W space velocity
76- 79 F4.2 --- e_WVel [0.02/5.7] WVel uncertainty
81- 85 A5 --- Prob TD to D probability ratio
87- 90 A4 --- Pop Population (G1)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
g = T0 spectral type from Schneider+, J/AJ/147/34 -- determined as a blue
L6 in this work; see Section 4.4 and Figure 15 for details.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 Gyr Age [6/12] Maximum age of the sample, τ
4- 4 A1 --- flag Flag (1)
6- 16 A11 --- SFR Star formation rate (2)
18- 29 A12 --- alpha Mass function power law index(ices) (3)
31- 35 A5 --- Models Brown dwarf evolution models (4)
37- 40 F4.2 Msun MBDM [0.01/0.03] Minimum brown dwarf mass
42- 44 F3.1 Gyr Mage [0.2/9.7] late-M dwarf age (5)
46- 48 F3.1 Gyr e_Mage [0.0/1.4] Uncertainty in Mage
50- 52 F3.1 Gyr Lage [1.7/9.6] L dwarf age (5)
54- 56 F3.1 Gyr e_Lage [0.3/1.3] Uncertainty in Lage
58- 60 F3.1 Gyr Tage [2.4/8.8] T dwarf age (5)
62- 64 F3.1 Gyr e_Tage [0.7/2.0] Uncertainty in Tage
66- 70 F5.1 --- chi2 [0.1/359.3] χ2 goodness of fit
--------------------------------------------------------------------------------
Note (1): Flags as follows:
a = Baseline simulation;
b = Simulations with an evolving mass function from top-heavy to
bottom-heavy over time using Baraffe+ (2003A&A...402..701B 2003A&A...402..701B)
evolutionary models. See Section 5.4 for details;
c = Simulations with an evolving mass function from bottom-heavy to
top-heavy over time using Baraffe+ (2003A&A...402..701B 2003A&A...402..701B)
evolutionary models. See Section 5.4 for details.
d = Baseline simulation with selection within 20pc and J or K<15.5.
See Section 6.1 for details.
e = Simulation with an artificial decrease in the HBMM for the
Baraffe+ (2003A&A...402..701B 2003A&A...402..701B) evolutionary models by fixing the
temperatures of brown dwarfs down to masses of 0.060Msun to their
1Gyr values. See Section 5.4 for details.
Note (2): Star formation rates considered in our simulations -- uniform;
exponential, Aumer & Binney (2009MNRAS.397.1286A 2009MNRAS.397.1286A); cosmic star
formation rate, Rujopakarn et al. (2010ApJ...718.1171R 2010ApJ...718.1171R).
Note (3): Evolving mass functions are labeled in the order of early α,
late α, and age (in Gyr) of transition.
The Chabrier (2003PASP..115..763C 2003PASP..115..763C) log-normal mass function is
labeled "C03".
Note (4): Brown dwarf evolution models are the following:
B03 = Baraffe et al. (2003A&A...402..701B 2003A&A...402..701B);
B01 = Burrows et al. (2001RvMP...73..719B 2001RvMP...73..719B);
S08 = Saumon & Marley (2008ApJ...689.1327S 2008ApJ...689.1327S);
M19 = Marley+ (2019 in prep.), https://doi.org/10.5281/zenodo.2628068;
P20C = Phillips et al. (2020arXiv200313717P 2020arXiv200313717P), chemical equilibrium;
P20NW = Phillips et al. (2020arXiv200313717P 2020arXiv200313717P), weak disequilibrium;
P20NS = Phillips et al. (2020arXiv200313717P 2020arXiv200313717P), strong disequilibrium.
Note (5): Kinematics ages computed using the
Aumer & Binney (2009MNRAS.397.1286A 2009MNRAS.397.1286A) relation and the procedure
described in Section 5.4
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Ref Reference code
5- 23 A19 --- BibCode Bibcode of the reference
25- 49 A25 --- Auth First author's name(s)
51- 71 A21 --- Comm VizieR catalog reference
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Global notes:
Note (G1): Galactic thin-disk (D), thick-disk (TD), and intermediate populations
(D/TD) are assigned according to probability ratios P(TD)/P(D)<0.1,
P(TD)/P(D)>10, and 0.1<P(TD)/P(D)<10, respectively, following
Bensby+ (2003, J/A+A/410/527).
--------------------------------------------------------------------------------
History:
From electronic version of the journal
Acknowledgements:
Dino Chih-Chun Hsu [chh194 at ucsd.edu]
References:
Faherty et al. Paper I. 2009AJ....137....1F 2009AJ....137....1F Cat. J/AJ/137/1
Faherty et al. Paper II. 2010AJ....139..176F 2010AJ....139..176F
Faherty et al. Paper III. 2012ApJ...752...56F 2012ApJ...752...56F Cat. J/ApJ/752/56
Burgasser et al. Paper IV. 2015ApJS..220...18B 2015ApJS..220...18B Cat. J/ApJS/220/18
Hsu et al. Paper V. 2021ApJS..257...45H 2021ApJS..257...45H This catalog
Hsu et al. Paper VI. 2024ApJS..274...40H 2024ApJS..274...40H Cat. J/ApJS/274/40
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-Mar-2022