J/AJ/167/253 89 new utlra cool dwarfs comoving companions (Rothermich+, 2024)
89 new ultracool dwarf comoving companions identified with the backyard worlds:
Planet 9 Citizen Science Project.
Rothermich A., Faherty J.K., Bardalez-Gagliuffi D., Schneider A.C.,
Kirkpatrick J.D., Meisner A.M., Burgasser A.J., Kuchner M., Allers K.,
Gagne J., Caselden D., Calamari E., Popinchalk M., Suarez G.,
Gerasimov R., Aganze C., Softich E., Hsu C.-C., Karpoor P., Theissen C.A.,
Rees J., Cecilio-Flores-Elie R., Cushing M.C., Marocco F., Casewell S.,
Bickle T.P., Hamlet L., Allen M.B., Beaulieu P., Colin G., Gantier J.M.,
Gramaize L., Jalowiczor P., Kabatnik M., Kiwy F., Martin D.W.,
Pendrill B., Pumphrey B., Sainio A., Schumann J., Stevnbak N., Sun G.,
Tanner C., Thakur V., Thevenot M., Wedracki Z.
<Astron. J., 167, 253 (2024)>
=2024AJ....167..253R 2024AJ....167..253R
ADC_Keywords: Stars, double and multiple; Stars, brown dwarf; Stars, T-type;
Stars, L-type; Positional data; Radial velocities;
Rotational velocities; Photometry, infrared
Keywords: Brown dwarfs ; Wide binary stars ; Astrometry ; Spectroscopy ;
Stellar rotation ; T dwarfs ; L dwarfs
Abstract:
We report the identification of 89 new systems containing ultracool
dwarf companions to main-sequence stars and white dwarfs, using the
citizen science project Backyard Worlds: Planet 9 and cross-reference
between Gaia and CatWISE2020. 32 of these companions and 33 host stars
were followed up with spectroscopic observations, with companion
spectral types ranging from M7-T9 and host spectral types ranging from
G2-M9. These systems exhibit diverse characteristics, from young to
old ages, blue to very red spectral morphologies, potential membership
to known young moving groups, and evidence of spectral binarity in
nine companions. 20 of the host stars in our sample show evidence for
higher-order multiplicity, with an additional 11 host stars being
resolved binaries themselves. We compare this sample's characteristics
with those of the known stellar binary and exoplanet populations, and
find our sample begins to fill in the gap between directly imaged
exoplanets and stellar binaries on mass ratio-binding energy plots.
With this study, we increase the population of ultracool dwarf
companions to FGK stars by ∼42%, and more than triple the known
population of ultracool dwarf companions with separations larger than
1000AU, providing excellent targets for future atmospheric retrievals.
Description:
Backyard Worlds: Planet 9 (BYW) is a citizen science project hosted on
the Zooniverse platform with the goal of identifying brown dwarfs
missed in previous searches, as well as objects within the solar
system. Citizen scientists visually inspect an animated "flipbook"
of time-resolved 704"x704" coadded unWISE images, obtained in the red
Wide-field Infrared Survey Explorer (WISE) W1-W2 (3.4-4.6um) bands.
Additionally, we performed a literature search for any existing
near-infrared photometry in 2MASS (Skrutskie+2006, VII/233), various
UKIRT surveys (e.g., UKIDSS: Lawrence+2007, II/314; UHS: Dye+,
2018MNRAS.473.5113D 2018MNRAS.473.5113D), and from the VISTA science archive (Cross+2012,
II/382) for both host and companion objects.
For all candidate host stars we gathered proper motions, parallaxes,
radial velocities, and rotational broadening (v.sin(i)) using Gaia DR3
(Gaia Collab+2022, I/355 & I/357) as well as abundances and
metallicity for select sources. Finally, further literature searches
were performed for any previously reported abundances or metallicity.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 148 187 High-probability comoving systems
table2.dat 150 186 Photometry of high-probability comoving systems
table11.dat 112 89 Binding energies and masses of high-probability
comoving systems
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See also:
B/pastel : The PASTEL catalogue (Soubiran+, 2016-)
III/123 : Dwarf K and M stars of small proper motion (Stephenson 1986)
I/146 : Positions and Proper Motions - North (Roeser+, 1988)
I/196 : Hipparcos Input Catalogue, Version 2 (Turon+ 1993)
II/179 : Southern Spectrophotometric Standards. I + II (Hamuy+ 1992,94)
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
II/335 : Revised cat. of GALEX UV src (GUVcat_AIS GR6+7) (Bianchi+ 2017)
III/279 : RAVE 5th data release (Kunder+, 2017)
IV/39 : TESS Input Catalog - v8.2 (TIC v8.2) (Paegert+, 2021)
II/365 : CatWISE2020 cat. (updated version 28-Jan-2021) (Marocco+, 2021)
II/382 : VIKING catalogue data release 4 (Cross+, 2012)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
V/136 : Teff and metallicities for Tycho-2 stars (Ammons+, 2006)
VII/233 : 2MASS All-Sky Extended Src Cat. (XSC) (IPAC/UMass, 2003-2006)
VI/135 : All-sky spectrally matched Tycho2 stars (Pickles+, 2010)
J/AJ/83/1090 : Late-type M dwarfs towards the SGP (Pesch+ 1978)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)
J/ApJ/637/1067 : NIR spec. classification of T dwarfs (Burgasser+, 2006)
J/A+A/460/695 : Search: Associations Containing Young stars (Torres+, 2006)
J/AJ/137/1 : Proper motion & astromet.: late-type dwarfs (Faherty+, 2009)
J/ApJ/699/649 : Young M dwarfs within 25pc. I. (Shkolnik+, 2009)
J/ApJS/190/100 : NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)
J/MNRAS/404/1817 : 2MASS/SDSS data for 806 ultracool dwarfs (Zhang+, 2010)
J/ApJ/752/56 : BDKP. III. Parallaxes: 70 ultracool dwarfs (Faherty+, 2012)
J/ApJ/779/188 : Spectra of nearby late K and M Kepler stars (Mann+, 2013)
J/ApJ/794/143 : New SpeX Observations of M7-L6 Dwarfs (Bardalez+, 2014)
J/AJ/148/54 : The Hypatia Catalog (Hinkel+, 2014)
J/ApJ/814/118 : L/T transition dwarfs search: PS1 & WISE. II. (Best+, 2015)
J/ApJS/216/7 : Planets Around Low-Mass Stars (PALMS). IV. (Bowler+, 2015)
J/ApJS/219/33 : BANYAN. VII. Candidate YMG members from BASS (Gagne+, 2015)
J/MNRAS/449/3651 : L and T dwarfs from UKIDSS LAS (Marocco+, 2015)
J/MNRAS/457/2192 : NCJM catalog of M dwarfs (Cook+, 2016)
J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)
J/ApJ/822/97 : Rot.-Activ. Correlations: K-M dwarfs. I. (Houdebine+, 2016)
J/ApJ/817/112 : NEOWISE/AllWISE high proper motion obj. (Schneider+, 2016)
J/A+A/589/A49 : Photometric brown-dwarf classification (Skrzypek+, 2016)
J/ApJ/842/118 : Brown dwarfs with spect. type later than T6 (Leggett+, 2017)
J/AJ/155/34 : Analysis: NIR spectra of neighboring L dwarfs (Cruz+, 2018)
J/A+A/619/L8 : Ultra-cool dwarfs candidates in Gaia DR2 (Reyle, 2018)
J/MNRAS/473/4937 : AllWISE ctp to ROSAT/2RXS & XMMSLEW2 cat. (Salvato+, 2018)
J/AJ/156/102 : TESS Input Catalog & Candidate Target List (Stassun+, 2018)
J/MNRAS/489/5301 : DES Y3 substellar LT and M catalogs (Carnero Rosell+, 2019)
J/AJ/158/56 : Stellar parameters of M and K dwarfs (Houdebine+, 2019)
J/ApJS/243/28 : M-type star magnetic activities: LAMOST & Kepler (Lu+, 2019)
J/ApJS/245/34 : Abundances: 6 million stars from LAMOST DR5 (Xiang+, 2019)
J/ApJ/889/74 : Spitzer follow-up of Y brown dwarfs (Meisner+, 2020)
J/ApJ/899/123 : Spitzer follow up of 95 brown dwarfs (Meisner+, 2020)
J/A+A/635/A43 : Stellar rot. periods: K2 Campaigns 0-18 (Reinhold+, 2020)
J/ApJ/891/23 : Stellar abundances from LAMOST MRS (SPCAnet) (Wang+, 2020)
J/ApJS/246/9 : Stellar parameters of LAMOST stars using SLAM (Zhang+, 2020)
J/ApJ/891/171 : COCONUTS. I. Spect. of WD & T4 comoving syst. (Zhang+, 2020)
J/ApJS/251/15 : LAMOST-Kepler/K2 survey (LK-MRS) 1st year obs. (Zong+, 2020)
J/ApJ/923/48 : Discovery of L dwarf co-moving BD+60 1417 (Faherty+, 2021)
J/ApJS/253/7 : Full-sky cens: brown dwarfs within 20pc (Kirkpatrick+, 2021)
J/A+A/645/A100 : SPECULOOS. Ultracool dwarf transit survey (Sebastian+, 2021)
J/AJ/161/63 : M dwarfs with M = 0.1 - 0.3Msun within 15pc (Winters+, 2021)
J/ApJS/260/45 : Stellar param of M-type stars from LAMOST DR8 (Ding+, 2022)
Byte-by-byte Description of file:table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Syst [1/89] System number; column and numbers added
by CDS
4- 29 A26 --- ID Object identifier
31 A1 --- m_ID [A/B] Component of the object identifier
33- 43 A11 --- Coord Truncated coordinates (HHMM+DDMM) or
alternative ID
45- 56 A12 --- SpType Spectral type (1)
58- 59 I2 --- r_SpType [1/34] Reference on SpType (2)
61- 67 F7.2 mas/yr pmRA [-556/367]? Proper motion in right ascension
(µα) from Gaia EDR3/DR3 (I/357)
69- 74 F6.2 mas/yr e_pmRA [0.01/119]? Uncertainty in pmRA
76- 82 F7.2 mas/yr pmDE [-490/185]? Proper motion in declination
(µδ) from Gaia EDR3/DR3 (I/357)
84- 89 F6.2 mas/yr e_pmDE [0.01/123]? Uncertainty in pmDE
91- 96 F6.2 km/s RVel [-79/76]? Radial velocity
98- 102 F5.2 km/s e_RVel [0.1/20]? Uncertainty in Rvel
104- 108 F5.2 km/s vsini [5/25]? Projected rotational velocity
110- 114 F5.2 km/s e_vsini [0.5/25]? Uncertainty in vsini
116 A1 --- f_plx [*] *: plx measurement from
Kirkpatrick+2021 (J/ApJS/253/7)
118- 122 F5.2 mas plx [3/57]? Parallax from Gaia EDR3/DR3 (I/357)
124- 127 F4.2 mas e_plx [0.01/5]? Uncertainty in plx
129 I1 --- r_plx [2/7]? References for plx measurement (2)
131- 136 F6.1 arcsec SepA [0.3/1124]? Angular separation from host star
138- 142 I5 AU SepL [5/4e4]? Linear separation from host star (3)
144- 148 F5.1 --- Prob [91/100]? Probability
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Note (1): Spectral types in parenthesis, e.g., (SpT), denote estimated spectral
types.
Note (2): References as follows:
1 = This work
2 = Gaia Collab+2023b (I/357)
3 = Marocco+2021 (II/365)
4 = Meisner+ (2023AJ....165...36M 2023AJ....165...36M)
5 = Nidever+ (2021AJ....161..192N 2021AJ....161..192N)
6 = Meisner+2020a (J/ApJ/889/74)
7 = Chambers+2016 (II/349)
8 = Spencer Jones & Jackson (1939cfsc.book.....S 1939cfsc.book.....S)
9 = Gentile Fusillo+2021 (J/MNRAS/508/3877)
10 = Pickles & Depagne, 2010 (VI/135)
11 = Xiang+2019 (J/ApJS/245/34)
12 = Turon+1993 (J/ApJS/245/34)
13 = Cook+2016 (J/MNRAS/457/2192)
14 = Pesch & Sanduleak, 1978 (J/AJ/83/1090)
15 = Torres+2006 (J/A+A/460/695)
16 = Cannon & Pickering, 1993 (III/135)
17 = Gaidos+2014 (J/MNRAS/443/2561)
18 = Winters+2021 (J/AJ/161/63)
19 = Stephenson, 1986 (III/123)
20 = Koester+ (2011A&A...530A.114K 2011A&A...530A.114K)
21 = Raddi+2017 (J/MNRAS/472/4173)
22 = Roeser & Bastian, 1988 (I/146)
23 = Skrzypek+2016 (J/A+A/589/A49)
24 = Sebastian+2021 (J/A+A/645/A100)
25 = Reyle, 2018 (J/A+A/619/L8)
26 = Gray+2006 (J/AJ/132/161)
27 = Marocco+2015 (J/MNRAS/449/3651)
28 = Vyssotsky & Balz (1958PMcCO..13b...0V 1958PMcCO..13b...0V)
29 = Houk & Cowley (1975mcts.book.....H 1975mcts.book.....H)
30 = Scholz, 2016 (J/A+A/587/A51)
31 = Zhang+2021 (J/ApJS/253/19)
32 = Shkolnik+2009 (J/ApJ/699/649)
33 = Malogolovets+ (2007AstBu..62..117M 2007AstBu..62..117M)
Note (3): Parallax measurement from Kirkpatrick+2021 (J/ApJS/253/7).
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Syst [1/89] System number; column and numbers added
by CDS
4- 29 A26 --- ID Object identifier
31 A1 --- m_ID [A/B] Component of the object identifier
33- 43 A11 --- Coord Truncated coordinates (HHMM+DDMM) or
alternative ID
45- 50 F6.3 mag Gmag [6.7/21]? Gaia DR3 (I/357) G (673nm) magnitude
52- 56 F5.3 mag e_Gmag [3e-3/0.02]? Uncertainty in Gmag
58- 63 F6.3 mag BPmag [6.9/22]? Gaia DR3 (I/357) BP (532nm) magnitude
65- 69 F5.3 mag e_BPmag [3e-3/0.31]? Uncertainty in BPmag
71- 76 F6.3 mag RPmag [6.3/20]? Gaia DR3 (I/357) RP (797nm) magnitude
78- 82 F5.3 mag e_RPmag [4e-3/0.11]? Uncertainty in RPmag
84- 88 F5.2 mag Jmag [6/21.4]? J-band (1.25um) magnitude (1)
90- 93 F4.2 mag e_Jmag [0/0.33]? Uncertainty in Jmag
95 A1 --- l_Hmag Lower limit ≥ on Hmag
97- 102 F6.3 mag Hmag [5.8/19.7]? H-band (1.65um) magnitude
104- 107 F4.2 mag e_Hmag [0.01/0.25]? Uncertainty in Hmag
109- 114 F6.3 mag Kmag [5.7/18.3]? K- and Ks-bands (2.20-2.17um)
magnitude (1)
116- 119 F4.2 mag e_Kmag [0/0.31]? Uncertainty in Kmag
121- 125 A5 --- RefNIR Near infrared references (2)
127 A1 --- l_W1mag Lower limit ≥ on W1mag
129- 134 F6.3 mag W1mag [5.9/20]? CatWISE2020 (II/365) W1 (3.35um)
magnitude
136- 139 F4.2 mag e_W1mag [0.01/0.33]? Uncertainty in W1mag
141- 145 F5.2 mag W2mag [5.7/18.3]? CatWISE2020 (II/365) W2 (4.6um)
magnitude
147- 150 F4.2 mag e_W2mag [0.01/0.54]? Uncertainty in W2mag
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Note (1): Both Mauna Kea Observatories (MKO) and Two Micron All Sky
Survey (2MASS, VII/233) filters.
Note (2): References as follows:
1 = 2MASS, Skrutskie+2006 (VII/233)
2 = 2MASS reject
3 = VISTA Hemisphere Survey, Cross+2012 (II/382)
4 = UKIRT Hemisphere Survey (UHS), Dye+ (2018MNRAS.473.5113D 2018MNRAS.473.5113D)
5 = UKIDSS Large Area Survey, Lawrence+2007 (II/314)
6 = UKIDSS Galactic Plane Survey, Lawrence+2007 (II/314)
8 = UKIDSS Galactic Clusters Survey, Lawrence+2007 (II/314)
9 = Meisner+2020a (J/ApJ/889/74)
10 = Best+2015 (J/ApJ/814/118)
11 = Leggett+2017 (J/ApJ/842/118)
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Byte-by-byte Description of file: table11.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Syst [1/89] System number; column and numbers
added by CDS
4- 29 A26 --- Host1 First host identifier
31- 32 A2 --- m_Host1 [AB] Composant of first host identifier
34- 55 A22 --- Host2 Second host identifier
57- 81 A25 --- Comp Companion identifier
83- 86 F4.2 Msun Mhost [0.05/1.53] Mass of the host MHost (1)
88- 91 F4.2 Msun Mcomp [0.01/0.11] Mass of the companion MComp
93- 96 F4.2 Msun Mtot [0.09/1.64] Total mass of the system
98- 101 F4.2 Msun Mrat [0.01/1] Mass ratio MComp/MHost
103- 107 F5.2 2.4e30W.h Ebind [0.1/21]? Binding energy
(in units of 1041 erg)
109 A1 --- l_tau Limit flag on tau
111- 112 I2 Gyr tau [2/14]? Estimated dissipation lifetime of
the system τ (2)
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Note (1): Host mass includes the masses of all known host system components,
i.e., both components A and B if the host was a binary.
Note (2): Calculated as described in Section 7.5:
Ebind = 1.8 x 105 x (MComp x MHost) / Separation
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History:
From electronic version of the journal
Acknowledgements:
Austin Rothermich ()
(End) Robin Leichtnam [CDS] 31-Jul-2025