J/AJ/158/182 Discoveries from the NEOWISE proper motion survey (Greco+, 2019)
Spectroscopic follow-up of discoveries from the NEOWISE proper motion survey.
Greco J.J., Schneider A.C., Cushing M.C., Kirkpatrick J.D., Burgasser A.J.
<Astron. J., 158, 182-182 (2019)>
=2019AJ....158..182G 2019AJ....158..182G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, brown dwarf ; Stars, dwarfs ; Stars, subdwarf ;
Spectral types ; Stars, distances ; Photometry, infrared ;
Proper motions ; Spectroscopy
Keywords: Brown dwarfs - L dwarfs - T dwarfs - M dwarf stars - L subdwarfs -
T subdwarfs - M subdwarf stars - Low mass stars - Spectroscopy
Infrared astronomy
Abstract:
We present low-resolution near-infrared spectra of discoveries from an
all-sky proper motion search conducted using multi-epoch data from the
Wide-field Infrared Survey Explorer. Using the data from NEOWISE, along
with the AllWISE catalog, Schneider et al. (2016, J/ApJ/817/112) conducted
an all-sky proper motion survey to search for nearby objects with high
proper motions. Here, we present a follow-up spectroscopic survey of 65
of their discoveries, which focused primarily on potentially nearby objects
(d<25 pc), candidate late-type brown dwarfs (≥L7), and subdwarf
candidates. We found 31 new M dwarfs, 18 new L dwarfs, and 11 new T dwarfs.
Of these, 13 are subdwarfs, including one new sdL1 and two new sdL7s.
Eleven of these discoveries, with spectral types ranging from M7 to T7
(including one subdwarf) are predicted to be within 25 pc, adding to
the number of known objects in the solar neighborhood. We also discovered
three new early-type T subdwarf candidates, one sdT1, one sdT2, and one
sdT3, which would increase the number of known early-type T subdwarfs
from two to five.
Description:
Spectra of 59 objects were obtained using the SpeX spectrograph
(Rayner et al. 2003PASP..115..362R 2003PASP..115..362R) on the NASA Infrared Telescope Facility
(IRTF) on Mauna Kea. Observations were conducted between the dates of
UT 2016 February 24 and UT 2017 November 22. Spectra of five objects were
obtained with the Folded-Port Infrared Echellete (FIRE; Simcoe et al.
2013PASP..125..270S 2013PASP..125..270S) spectrograph on the Magellan 6.5 m Baade Telescope
at Las Campanas Observatory. Observations were conducted on UT 2016
July 18. One object was observed on UT 2016 December 9 with Astronomy
Research using the Cornell Infrared Imaging Spectrograph (ARCoIRIS) on
the 4 m Blanco telescope located at the Cerro Tolo Inter-American
Observatory (CTIO).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 79 65 Summary of observations
table2.dat 141 16 Subdwarf standards
table3.dat 50 65 Spectral types
table4.dat 98 65 Object distances
table5.dat 136 65 Photometry, proper motions, spectral types, and
tangential velocities of all observed objects
figs/* . 65 Spectra of the objects shown in Figures 1-6
fig7/* . 16 Spectra of the subdward standards shown
in Figure 7
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
J/ApJ/817/112 : NEOWISE/AllWISE high proper motion objects (Schneider+, 2016)
J/ApJS/224/36 : The AllWISE motion survey (AllWISE2) (Kirkpatrick+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- AllWISE AllWISE designation (JHHMMSS.ss+DDMMSS.s) (1)
21- 31 A11 "date" Date UT date of observation
33- 45 A13 --- Tel Telescope/Instrument used
47- 50 I4 s ExpTime [714/2880] Total exposure time
52- 60 A9 --- Star A0 V star observed for calibration purposes
(HD NNNNNN)
62- 64 I3 --- S/N [7/533] Signal-to-noise ratio (G1)
66- 79 A14 --- FileName File name with spectrum in subdirectory figs
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Note (1): The prefix for AllWISE sources is WISEA. So for example
J000430.66-260402.3 should be listed as WISEA J000430.66-260402.3.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name Object name
26- 33 A8 --- OName Other designation
35- 40 A6 --- SpType Optical spectral type
42 A1 --- n_SpType [cefg] Note on SpType (1)
44- 73 A30 --- r_SpType Spectral type reference
75- 93 A19 --- Bibcode Bibcode of the reference
95 A1 --- nrSpType [d] Note on r_SpType (2)
97-107 A11 "date" Date UT date of observation
109-112 I4 s ExpTime [320/1440] Exposure time (3)
114-122 A9 --- Star A0 V star observed (HD NNNNNN) (3)
124-126 I3 --- S/N [60/758] Signal-to-noise ratio (G1)
128-141 A14 --- FileName File name with spectrum in subdirectory
fig7
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Note (1): Note as follows:
c = Kirkpatrick et al. (2010, J/ApJS/190/100) classify this object in the
near-infrared as <esdM5;
e = Burgasser et al. (2004, J/AJ/127/2856) classify this object in the
near-infrared as similar to, or slightly later than, sdM7.5;
f = Kirkpatrick et al. (2010, J/ApJS/190/100) classify this object in the
near-infrared as L1 pec (blue);
g = Kirkpatrick et al. (2010, J/ApJS/190/100) classify this object in the
near-infrared as sdL7.
Note (2): Note as follows:
d = Riaz et al. (2008ApJ...672.1153R 2008ApJ...672.1153R) reference Ruiz & Anguita
(1993AJ....105..614R 1993AJ....105..614R) for the spectral type, which provides a spectrum but
no spectral type.
Note (3): Exact exposure times and which A0V stars were used could not be
determined because the original FITS headers from the reduction were lost.
Therefore we estimated the exposure times and standards using the raw data
frames obtained form the IRTF Legacy Archive
(http://irtfdata.ifa.hawaii.edu/search/).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- AllWISE AllWISE designation (JHHMMSS.ss+DDMMSS.s)
21 A1 --- l_SpTypeP [<] Limit flag on SpTypeP
22- 26 A5 --- SpTypeP Photometric spectral type (1)
28 A1 --- n_SpTypeP [d] Note on SpTypeP (2)
30- 42 A13 --- SpTypeO Spectral type from observations (G2)
44- 50 A7 --- Cat Follow-up category (3)
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Note (1): Estimated spectral types are from Schneider et al. (2016,
J/ApJ/817/112). They are numerical spectral types where, for example, M2=2,
L2=12, T2=25, etc.
Note (2): Note as follows:
d = WISE 0309-5016 does not show up in 2MASS, so a precise numerical spectral
type could not be determined. Instead, an estimate was made based on the
W1-W2 color. See Section 3.4 of Schneider et al. (2016, J/ApJ/817/112) for
details.
Note (3): Lists which of our follow-up categories an object belonged to:
n = Nearby;
s = Subdwarf;
l = Late-type;
g = Gap object;
w = Poor weather target.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- AllWISE AllWISE designation (JHHMMSS.ss+DDMMSS.s)
21- 33 A13 --- SpTypeO Spectral type (G2)
35- 36 I2 pc b_DistS [9/24]? Distance from Schneider et al. (2016,
J/ApJ/817/112), lower value (1)
38- 39 I2 pc B_DistS [13/37]? Distance from Schneider et al. (2016,
J/ApJ/817/112), upper value (1)
41- 43 I3 pc Dist [12/160] Distance from this work
45- 48 F4.1 pc e_Dist [1/24] Uncertainty in Dist
49 A1 --- n_Dist [f] Note on Dist (2)
51- 69 I19 --- Source ? Gaia source identifier (3)
71- 76 F6.2 pc DistG [19.27/181]? Gaia DR2 distance (4)
78- 82 F5.2 pc e_DistG [0.03/26]? Lower limit uncertainty in DistG
84- 88 F5.2 pc E_DistG [0.03/47]? Upper limit uncertainty in DistG
90- 93 F4.1 pc DistK [13.3/15]? Distance from Kirkpatrick et al.
(2019ApJS..240...19K 2019ApJS..240...19K) (5)
95- 98 F4.2 pc e_DistK [0.81/0.87]? Uncertainty in DistK
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Note (1): Only listed for objects that were nearby candidates in the
Schneider et al. (2016, J/ApJ/817/112) survey.
Note (2): Note as follows:
f = This is the distance we calculated, assuming this object is a subdwarf.
In the absence of this assumption, the distance would be 260±31 pc.
Note (3): Only listed for objects with matches in Gaia DR2 (Cat. I/345).
Note (4): Taken from Bailer-Jones et al. (2018, Cat. I/347).
Note (5): Only listed for three objects, which were included in
Kirkpatrick et al. (2019ApJS..240...19K 2019ApJS..240...19K).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- AllWISE AllWISE designation (JHHMMSS.ss+DDMMSS.s)
20 A1 --- n_AllWISE [a] Note on AllWISE (1)
22 A1 --- l_Jmag [>] Limit flag on Jmag
23- 28 F6.3 mag Jmag [12.04/17.338]? 2MASS J band magnitude
30- 34 F5.3 mag e_Jmag [0.021/0.235]? Uncertainty in Jmag
35 A1 --- n_Jmag [b] Note on Jmag (2)
37 A1 --- l_Hmag [>] Limit flag on Hmag
38- 43 F6.3 mag Hmag [11.425/16.669]? 2MASS H band magnitude
45- 49 F5.3 mag e_Hmag [0.021/0.24]? Uncertainty in Hmag
51 A1 --- l_Ksmag [>] Limit flag on Ksmag
52- 57 F6.3 mag Ksmag [11.035/16.262]? 2MASS Ks band magnitude
59- 63 F5.3 mag e_Ksmag [0.018/0.267]? Uncertainty in Ksmag
65- 70 F6.3 mag W1mag [10.796/16.804] WISE W1 band (3.4µm)
magnitude
72- 76 F5.3 mag e_W1mag [0.022/0.065] Uncertainty in W1mag
78- 83 F6.3 mag W2mag [10.596/16.121] WISE W2 band (4.6µm)
magnitude
85- 89 F5.3 mag e_W2mag [0.02/0.085] Uncertainty in W2mag
91- 96 F6.1 mas/yr pmRA [-572.2/591.3]? Proper motion along RA
µα
98-101 F4.1 mas/yr e_pmRA [5.9/31.2]? Uncertainty in pmRA
103-108 F6.1 mas/yr pmDE [-557.8/476.7]? Proper motion along DE
µδ
110-113 F4.1 mas/yr e_pmDE [5.9/30.3]? Uncertainty in pmDE
115-117 I3 km/s vtan [16/360]? Tangential velocity
119-122 F4.1 km/s e_vtan [1.7/54]? Uncertainty in vtan
124-136 A13 --- SpType Spectral type
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Note (1): Note as follows:
a = WISE 030919.70-501614.2 does not show up in 2MASS, and therefore does not
have a 2MASS-AllWISE proper motion, and also does not have a calculated
vtan.
Note (2): Note as follows:
b = The 2MASS J-band photometry for WISE 032309.12-590751.0 was taken from
the 2MASS reject table.
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Byte-by-byte Description of file: figs/*
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Bytes Format Units Label Explanations
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1- 10 F10.8 um Wave Wavelength
12- 29 E18.12 10-2W/m2/nm Flux ? Flux density (in ergs/s/cm2/Å)
31- 43 E13.8 10-2W/m2/nm e_Flux ? Uncertainty in Flux (in ergs/s/cm2/Å)
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Byte-by-byte Description of file: fig7/*
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Bytes Format Units Label Explanations
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1- 14 F14.12 um Wave Wavelength
16- 32 E17.12 10-2W/m2/nm Flux ? Flux density (in ergs/s/cm2/Å)
34- 49 E16.11 10-2W/m2/nm e_Flux ? Uncertainty in Flux (in ergs/s/cm2/Å)
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Global notes:
Note (G1): Calculated at the peak intensity in the J-band.
Note (G2): Spectral types as determined by comparing our SpeX Prism spectra with
spectral standards. Subdwarf spectral types are denoted by the following
abbreviations: sd=subdwarf, d/sd=dwarf/subdwarf, and esd=extreme subdwarf.
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 06-Jan-2020