J/ApJS/225/10 Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)
Population properties of brown dwarf analogs to exoplanets.
Faherty J.K., Riedel A.R., Cruz K.L., Gagne J., Filippazzo J.C.,
Lambrides E., Fica H., Weinberger A., Thorstensen J.R., Tinney C.G.,
Baldassare V., Lemonier E., Rice E.L.
<Astrophys. J. Suppl. Ser., 225, 10-10 (2016)>
=2016ApJS..225...10F 2016ApJS..225...10F (SIMBAD/NED BibCode)
ADC_Keywords: Stars, late-type ; Radial velocities ; Spectral types ;
Parallaxes, spectroscopic ; Proper motions ; Spectra, infrared ;
Stars, masses ; Effective temperatures ; Photometry, infrared
Keywords: astrometry; brown dwarfs; stars: low-mass
Abstract:
We present a kinematic analysis of 152 low surface gravity M7-L8
dwarfs by adding 18 new parallaxes (including 10 for comparative field
objects), 38 new radial velocities, and 19 new proper motions. We also
add low- or moderate-resolution near-infrared spectra for 43 sources
confirming their low surface gravity features. Among the full sample,
we find 39 objects to be high-likelihood or new bona fide members of
nearby moving groups, 92 objects to be ambiguous members and 21
objects that are non-members. Using this age-calibrated sample, we
investigate trends in gravity classification, photometric color,
absolute magnitude, color-magnitude, luminosity, and effective
temperature.
Description:
The sample of 152 M7-L8 ultra-cool dwarfs comprising our sample (see
table 1) were placed on follow-up programs --either imaging (parallax,
proper motion), spectroscopy (radial velocity), or both-- to determine
kinematic membership in a nearby moving group.
For Northern Hemisphere astrometry targets, we obtained I-band images
with the MDM Observatory 2.4m Hiltner telescope on Kitt Peak, Arizona.
We also observed 16 of the most southern targets with the Carnegie
Astrometric Planet Search Camera (CAPSCam) on the 100 inch du Pont
telescope and 5 with the FourStar imaging camera on the Magellan Baade
Telescope.
Table 2 gives the pertinent astrometric information; Table 3 lists our
measured parallaxes and proper motions. New proper-motion measurements
are listed in Table 5. See also section 3.1.
We used the 6.5m Baade Magellan telescope and the FIRE spectrograph to
obtain near-infrared spectra of 36 sources. Observations were made
over seven runs between 2013 July and 2014 September. All observations
(resolution R∼6000) cover the full 0.8-2.5um band with a spatial
resolution of 0.18"/pixel.
We used the 3m NASA IRTF to obtain low-resolution near-infrared
spectroscopy for 10 targets. All of the observations were aligned to
the parallactic angle to obtain R∼120 spectral data over the
wavelength range of 0.7-2.5um.
We used the Triple Spectrograph (TSpec) at the 5m Hale Telescope at
Palomar Observatory to obtain near-infrared spectra of two targets.
TSpec covers simultaneously the range from 1.0 to 2.45um and achieves
a resolution of ∼2500.
Exposure times for each source and the number of images acquired are
listed in Table 6; see also section 3.2.
Multiple observations of 17 sources were taken in high-resolution mode
on Keck II on 2008 September 14-16, using the NIRSPEC-5 filter to
obtain H-band spectra in Order 49 (1.545-1.570um ).
Observations of 18 sources were taken during semesters 2007B and 2009B
using the H6420 filter of the Phoenix instrument (previously on Gemini
South) to select H-band spectra in Order 36 (1.551-1.558um).
Red-side spectra were taken with MIKE on the Magellan II (Clay)
telescope on 2006 July 4, 2006 November 1 and 2 for 17 targets.
Observational data for each source are listed in Table 7; see also
section 3.3.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 156 152 Photometric properties of low surface gravity dwarfs
table2.dat 67 18 Details on parallax targets and observations
table3.dat 78 18 Results of parallax program
table5.dat 89 33 New proper-motion measurements
table6.dat 60 52 Near-infrared spectral data for 43 sources
table7.dat 97 61 Radial velocities from high resolution spectroscopy
for 50 sources
table10.dat 134 152 Kinematic data on low surface gravity dwarfs
table12.dat 134 152 *Moving group membership probabilities
table14.dat 108 69 Fundamental parameters for young sources
refs.dat 103 79 References (60 unique)
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Note on table12.dat: Computations of BANYAN I and II were done with the web
calculator, without photometric data. BANYAN II and LACEwING were computed
assuming the objects are young. The predicted distance and RV (as predicted
by LACEwING for the final group) should be compared to the values in Table 10.
--------------------------------------------------------------------------------
See also:
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150 - 25000 A (Pickles 1998)
J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/AJ/127/3553 : JHK photometry & spectroscopy for L & T dwarfs (Knapp+, 2004)
J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)
J/A+A/441/653 : 32 DENIS nearby red dwarfs (Crifo+, 2005)
J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)
J/ApJ/651/502 : Spitzer IRAC photometry of M, L, and T dwarfs (Patten+, 2006)
J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)
J/AJ/133/2825 : Star beyond the NLTT catalog (Reid+, 2007)
J/AJ/133/2258 : Activity and kinematics of ultracool dwarfs (Schmidt+, 2007)
J/ApJ/689/1295 : Lithium test implications for BDs (Kirkpatrick+, 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/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)
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 <20pc (Reiners+, 2009)
J/ApJ/723/684 : NIRSPEC ultracool dwarf radial velocity survey (Blake+, 2010)
J/ApJ/710/1142 : SpeX spectroscopy of low mass binaries. I. (Burgasser+, 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/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)
J/ApJ/752/56 : BDKP. III. Parallaxes for 70 ultracool dwarfs (Faherty+, 2012)
J/A+A/540/A85 : Spectroscopy of very low mass objects (Patience+, 2012)
J/ApJ/758/56 : Young M dwarfs within 25pc. II. Kinematics (Shkolnik+, 2012)
J/ApJ/762/88 : Young stellar kinematic group candidate members (Malo+, 2013)
J/PASP/125/809 : New nearby M, L, and T dwarfs (Thompson+, 2013)
J/AJ/147/94 : Solar neighborhood. XXXII. L and M dwarfs (Dieterich+, 2014)
J/ApJ/784/156 : Parallaxes for nearby mid-to-late M dwarfs (Dittmann+, 2014)
J/ApJ/783/121 : BANYAN II. Nearby young assoc. cand. members (Gagne+, 2014)
J/AJ/147/34 : SpeX library of L-type dwarfs (Schneider+, 2014)
J/ApJ/814/118 : L/T transition dwarfs with PS1 & WISE. II. (Best+, 2015)
J/ApJS/220/18 : BDKP IV. RVs of late-M & L dwarfs with MagE (Burgasser+, 2015)
J/ApJS/219/33 : BANYAN. VII. Candidate YMG members from BASS (Gagne+, 2015)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000) or
other name
20- 22 A3 --- f_2MASS Flag(s) on 2MASS (G1)
24- 28 A5 --- OSpT Optical MK spectral type
30- 35 A6 --- OGrav Gravity assigned on optical spectra (1)
37- 42 A6 --- IRSpT Infrared MK spectral type (or range)
44- 53 A10 --- IGrav Gravity assigned on IR spectra (1)
55 A1 --- f_IRSpT Flag on ITSpT (G1)
57- 62 F6.3 mag Jmag [8.3/17.7] 2MASS J-band magnitude
64- 68 F5.3 mag e_Jmag [0.01/0.3] Jmag uncertainty
70- 75 F6.3 mag Hmag [7.8/16.2] 2MASS H-band magnitude
77- 81 F5.3 mag e_Hmag [0.01/0.3] Jmag uncertainty
83- 88 F6.3 mag Ksmag [7.5/15.3] 2MASS Ks-band magnitude
90- 94 F5.3 mag e_Ksmag [0.01/0.2] Ksmag uncertainty
96-101 F6.3 mag W1mag [7.3/14.8]? WISE W1 band (3.4um) magnitude
103-107 F5.3 mag e_W1mag [0.02/0.04]? W1mag uncertainty
109-114 F6.3 mag W2mag [7/14.4]? WISE W2 band (4.6um) magnitude
116-120 F5.3 mag e_W2mag [0.01/0.06]? W2mag uncertainty
122-127 F6.3 mag W3mag [6.8/13.4]? WISE W3 band (12um) magnitude
129-133 F5.3 mag e_W3mag [0.01/0.6]? W3mag uncertainty
135-139 F5.3 mag W4mag [5/9.8]? WISE W4 band (22um) magnitude
141-145 F5.3 mag e_W4mag [0.02/0.6]? W4mag uncertainty
147-156 A10 --- Ref Reference(s) for the spectral data and
gravity analysis (see refs.dat file) (2)
--------------------------------------------------------------------------------
Note (1): The Cruz+ (2009AJ....137.3345C 2009AJ....137.3345C) system uses optical spectra and
assigns a low surface gravity (γ),
intermediate gravity (β), or field gravity ("-") based on the
strength of metal oxide absorption bands and alkali lines.
See section 2 for further explanations.
Note (2): References are for the spectral data and gravity analysis (if
different then the original spectral data reference).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
20- 28 A9 --- OSpT Optical spectral type
30- 38 A9 --- IRSpT Infrared spectral type
40 I1 --- Nn [3/7] Number of nights
42- 43 I2 --- Nf [17/90] Number of frames (1)
45- 46 I2 --- Ns [10/81] Number of reference stars (1)
48- 50 F3.1 yr Delt [2.2/9.9] Δt value
52- 57 A6 --- Tel Telescope (see the "Description" section above)
59- 60 A2 --- Note Note (LG=low surface gravity object;
N=field object)
62- 67 A6 --- Ref References (see refs.dat file)
--------------------------------------------------------------------------------
Note (1): The number of reference stars and individual image frames used in
the parallax solution.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
20- 28 A9 --- OSpT Optical spectral type
30- 38 A9 --- IRSpT Infrared spectral type
40- 46 F7.4 arcsec/yr pmRA [-0.9/0.5] Proper motion
along right ascension (µα)
48- 53 F6.4 arcsec/yr e_pmRA [0.0008/0.01] pmRA uncertainty
55- 61 F7.4 arcsec/yr pmDE [-1.3/0.2] Proper motion
along declination (µδ)
63- 68 F6.4 arcsec/yr e_pmDE [0.0009/0.01] pmDE uncertainty
70- 74 F5.1 mas Plx [17/115] Parallax (πabs)
76- 78 F3.1 mas e_Plx [1.6/7.4] Plx uncertainty
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
or other name
20- 30 A11 --- OSpT Optical spectral type
32- 46 A15 --- IRSpT Infrared spectral type
48- 53 F6.3 arcsec/yr pmRA [-0.2/0.3] Proper motion
along right ascension (µR.A.)
55- 59 F5.3 arcsec/yr e_pmRA [0.005/0.04] pmRA uncertainty
61- 66 F6.3 arcsec/yr pmDE [-0.3/0.08] Proper motion
along declination (µdecl.)
68- 72 F5.3 arcsec/yr e_pmDE [0.004/0.02] pmDE uncertainty
74- 83 A10 --- Ref References
(see the "Description" section above)
85- 89 F5.2 yr Delt [9.5/17] Δt value (1)
--------------------------------------------------------------------------------
Note (1): In the case of the 18 proper-motion-only targets from either CAPSCam
or FourStar, we combine our latest image with that of 2MASS.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
or other name
20 I1 --- m_2MASS ? When multiple observations of the same object
22- 32 A11 --- Date UT date of observation
34- 38 A5 --- Inst Instrument (see the "Description" section above)
40- 46 A7 --- Mode Mode
48- 53 A6 arcsec Slit Slit
55- 58 I4 s Exp [90/1500] Integration time
60 I1 --- Nimg [2/8] Number of images
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
20- 24 A5 --- f_2MASS Flag(s) on 2MASS (1)
26- 45 A20 --- Tel Telescope (see the "Description" section above)
47- 51 I5 --- R [20000/50000] Resolving power
53- 63 A11 --- Date UT date of observation
65- 71 A7 --- Std Standards used (2)
73- 78 F6.2 km/s RV [-39.2/52]? Radial velocity
80- 84 F5.2 km/s e_RV [0.01/15.1]? RV uncertainty
86- 91 F6.2 km/s RVf [-39.2/52]? RV final
93- 97 F5.2 km/s e_RVf [0.01/15.1]? RVf uncertainty
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = Low-quality Spectrum.
b = No useable spectrum.
c = No spectroscopic signs of youth.
d = This object is listed in Filippazzo+ (2015ApJ...810..158F 2015ApJ...810..158F) with
a distance and reference to J. Faherty 2016, in preparation. The value
in that paper was spectrophotometric and should not be regarded as
a parallax.
Note (2): Standard stars are as follows:
1 = 2MASS J18212815+1414010 (+9.78 Blake+ 2010, J/ApJ/723/684),
2 = 2MASS J00452143+1634446 (+3.29 Blake+ 2010, J/ApJ/723/684),
3 = 2MASS J22244381-0158521 (-37.55 Blake+ 2010, J/ApJ/723/684),
4 = LHS 2924 (-37.4 Mohanty+ 2003ApJ...593L.109M 2003ApJ...593L.109M),
5 = BRI 1222-1221 (-4.8 Mohanty+ 2003ApJ...593L.109M 2003ApJ...593L.109M),
6 = 2MASS J11553952-3727350 (+45.0 Seifahrt+ 2010, J/A+A/512/A37),
7 = 2MASS J05233822-1403022 (+11.82 Blake+ 2007ApJ...666.1198B 2007ApJ...666.1198B)
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Byte-by-byte Description of file: table10.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
or other name
20- 22 A3 --- f_2MASS Flag on 2MASS (G1)
24- 28 A5 --- OSpT Optical MK spectral type
30- 35 A6 --- OGrav Gravity associated to OSpT
37- 42 A6 --- IRSpT Infrared MK spectral type
44- 53 A10 --- IGrav Gravity associated to IRSpT
55 A1 --- f_IRSpT Flag on IRSpT (G1)
57- 64 F8.5 arcsec/yr pmRA [-0.9/1.6] Proper motion
along right ascension (µR.A.cosdecl.)
66- 72 F7.5 arcsec/yr e_pmRA [0.0001/0.1] pmRA uncertainty
74- 82 F9.6 arcsec/yr pmDE [-0.8/0.5] Proper motion
along declination (µdecl.)
84- 90 F7.5 arcsec/yr e_pmDE [0.0001/0.3] pmDE uncertainty
92- 97 F6.2 mas Plx [1.9/261]? Parallax
99-103 F5.2 mas e_Plx ? Plx uncertainty
105-106 I2 pc Dist ? Kinematic distance
108 I1 pc e_Dist ? Dist uncertainty
110-116 F7.3 km/s RV [-25.6/34]? Radial velocity
118-122 F5.3 km/s e_RV [0.04/8]? RV uncertainty (or negative
uncertainty if E_RV is filled)
124-126 F3.1 km/s E_RV ? Positive error on RV
127 A1 --- u_RV Uncertainty flag on RV
129-134 A6 --- Ref2 Reference(s) (see refs.dat file)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table12.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
or other name
20- 22 A3 --- f_2MASS Flag on 2MASS (G1)
24- 28 A5 --- OSpT Optical MK spectral type
30- 35 A6 --- OGrav Gravity assigned on optical spectra
37- 42 A6 --- IRSpT Infrared MK spectral type
44- 53 A10 --- IGrav Gravity assigned on infrared spectra
55 A1 --- f_IRSpT [a] Flag on IRSpT (G1)
57 A1 --- l_PBII Limit flag on PBII
59- 63 F5.1 --- PBII [0/100]? BANYANII Gagne+ (2014, J/ApJ/783/121)
membership probability
65 A1 --- l_CBII Limit flag on CBII
67- 74 F8.4 --- CBII [0/100]? BANYANII contamination
76- 83 A8 --- GBII BANYAN II group designation
85- 90 F6.2 --- PL [0/100] LACEwING (Riedel 2017AJ....153...95R 2017AJ....153...95R)
membership probability
92- 99 A8 --- GL LACEwING group designation
101-105 F5.1 --- PC [0/100]? Convergent Point method (Rodriguez+
2013ApJ...774..101R 2013ApJ...774..101R) membership probability
107-114 A8 --- GC Convergent Point group designation
116-121 F6.2 --- PBI [40/100] BANYAN I (Malo+, 2013, J/ApJ/762/88)
membership probability
123-130 A8 --- GBI BANYAN I group designation
132-134 A3 --- Mm Membership decision (3)
--------------------------------------------------------------------------------
Note (3): Categories of membership probability as follows:
NM = non-member: an object that is kinematically eliminated from falling
into a nearby group regardless of future astrometric measurements
(21 sources).
AM = Ambiguous member: an object that requires updated astrometric precision
because it could either belong to more than one group or it cannot be
differentiated from the field (92 sources).
HLM = High-likelihood member: an object that does not have full kinematics
but is regarded as high confidence (>90% in Banayan I, >90% in Banyan II
with <5% contamination, >90% in convergent point, >60% in LACEwING) in
three of the four codes (29 sources).
BM = bona fide member: an object regarded as a high-likelihood member with
full kinematics (parallax, proper motion, radial velocity) demonstrating
that it is in line with known higher-mass BMs of nearby groups
(10 sources).
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Byte-by-byte Description of file: table14.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- 2MASS 2MASS designation (HHMMSSss+DDMMSSs; J2000)
or other name
20- 24 A5 --- OSpT Optical MK spectral type
26- 31 A6 --- OGrav Gravity assigned on optical spectra
33- 38 A6 --- IRSpT Infrared MK spectral type
40- 49 A10 --- IGrav Gravity assigned on infrared spectra
51 A1 --- f_IRSpT [a] Flag on IRSpT (G1)
53- 58 F6.2 mas Plx [1.9/260.7]? Parallax
60- 64 F5.2 mas e_Plx [0.2/11.5]? Plx uncertainty
66- 67 I2 pc Dist [15/54]? Kinematic distance
69 I1 pc e_Dist [1/9]? Dist uncertainty
71- 76 F6.3 --- Lbol [-4.6/-2.5]? Bolometric luminosity (1)
78- 82 F5.3 --- e_Lbol [0.005/0.4]? Lbol uncertainty
84- 89 F6.1 K Teff [1184/2986]? Effective temperature (1)
91- 95 F5.1 K e_Teff [10/526]? Teff uncertainty
97-102 F6.2 Mjup Mass [6/122]? Mass (1)
104-108 F5.2 Mjup e_Mass [0.7/49]? Mass uncertainty
--------------------------------------------------------------------------------
Note (1): Lbol, Teff, and Mass are calculated as described in
Filippazzo+ (2015ApJ...810..158F 2015ApJ...810..158F). Values that are slightly different
from that work have been updated using new data presented in this
paper.
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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- 46 A22 --- Auth First author's name(s)
48-103 A56 --- Comm Comment
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Global notes:
Note (G1): Flag as follows:
a = These sources have new infrared spectra presented in this paper. In the
majority of cases, we use the infrared spectral type and gravity
classification diagnosed in this work. If an object had SpeX data, we
defaulted to the resultant type and classification with that data.
b = This source is referred to as PSO318 for the remainder of the text.
c = The sources PSO318, 2M1119, and 2M1147 have photometry reported on the
MKO system that we have converted to 2MASS using the relations in
Stephens+ (2009ApJ...702..154S 2009ApJ...702..154S).
In the case of PSO318, JHK was converted to MKO, whereas J and H were
converted for 2M119, and only J was converted for 2M1147.
d = Teegardens Star.
e = Deacon+ (2016MNRAS.457.3191D 2016MNRAS.457.3191D) use the parallax reported in this work to
show that this source is co-moving with the M dwarf TYC 9486-927-1. In
that work, they report a likelihood of membership in the β pictoris
moving group, however, we find this to be unlikely with the given
kinematics. The membership of this interesting wide system remains
unknown.
f = Referred to as TVLM831-154910 in Tinney+ (1995AJ....110.3014T 1995AJ....110.3014T).
g = The source 0335+2342 is listed as a bona fide member of β Pictoris
in Gagne+ (2014, J/ApJ/783/121) using a 2MASS to WISE proper motion.
Aside from the Shkolnik+ (2012, J/ApJ/758/56) proper motion used in this
work, this source also has a PPMXL proper motion. Depending on which
value is used in the kinematic analysis, the probability of membership
varies. Based on its position on the various photometric and absolute
magnitude diagrams in this work, we suspect this source is a
β Pictoris member. However, refined kinematics will confirm this.
Furthermore, Allers & Liu (2013ApJ...772...79A 2013ApJ...772...79A) list this object as an
M7 VLG source, however, we have chosen to list it as an M7.5 β based
on the analysis in Gagne+ (2014, J/ApJ/783/121).
z = These sources were listed in Filippazzo+ (2015ApJ...810..158F 2015ApJ...810..158F) as members
of associations but, as has been noted in Table 12, we have downgraded
them to ambiguous young objects.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 09-Aug-2017