J/AJ/154/147 Astrometry&photometry for late-type dwarfs&subdwarfs (Dahn+, 2017)
CCD parallaxes for 309 late-type dwarfs and subdwarfs.
Dahn C.C., Harris H.C., Subasavage J.P., Ables H.D., Canzian B.J.,
Guetter H.H., Harris F.H., Henden A.H., Leggett S.K., Levine S.E.,
Luginbuhl C.B., Monet A.B., Monet D.G., Munn J.A., Pier J.R., Stone R.C.,
Vrba F.J., Walker R.L., Tilleman T.M.
<Astron. J., 154, 147 (2017)>
=2017AJ....154..147D 2017AJ....154..147D (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Stars, subdwarf ; Stars, late-type ;
Positional data ; Parallaxes, trigonometric ; Proper motions ;
Photometry, VRI ; Photometry, infrared ; Spectral types
Keywords: astrometry - parallaxes - proper motions - stars: distances -
stars: late-type - subdwarfs
Abstract:
New, updated, and/or revised CCD parallaxes determined with the Strand
Astrometric Reflector at the Naval Observatory Flagstaff Station are
presented. Included are results for 309 late-type dwarf and subdwarf
stars observed over the 30+ years that the program operated. For 124
of the stars, parallax determinations from other investigators have
already appeared in the literature and we compare the different
results. Also included here are new or updated VI photometry on the
Johnson-Kron-Cousins system for all but a few of the faintest targets.
Together with 2MASS JHKs near-infrared photometry, a sample of
absolute magnitude versus color and color versus color diagrams are
constructed. Because large proper motion was a prime criterion for
targeting the stars, the majority turn out to be either M-type subdwarfs
or late M-type dwarfs. The sample also includes 50 dwarf or subdwarf
L-type stars, and four T dwarfs. Possible halo subdwarfs are identified
in the sample based on tangential velocity, subluminosity, and
spectral type. Residuals from the solutions for parallax and proper
motion for several stars show evidence of astrometric perturbations.
Description:
In this paper, we present a compilation of NOFS CCD parallaxes for all
309 of the late-type dwarf and subdwarf stars that have been observed
with the Strand Astrometric Telescope. The results presented here
include all observations obtained through 2016 June.
Photometry in the V and I bands of the Johnson-Kron-Cousins system
(Cousins 1976MmRAS..81...25C 1976MmRAS..81...25C, 1980SAAOC...1..234C 1980SAAOC...1..234C) was measured for
both the astrometric reference stars and parallax targets in most of
the fields using the NOFS 1.0 m reflector. The secondary photometric
standards from Landolt (1983, Cat. II/118; 1992AJ....104..340L 1992AJ....104..340L; 2007,
J/AJ/133/2502; 2013, J/AJ/146/131) were employed. Further details
regarding our photometric measures can be found in Dahn et al.
(2002AJ....124.1170D 2002AJ....124.1170D, Section 3.1).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 165 313 Astrometric Results
table2.dat 54 308 Astrometric Comparisons
table3.dat 90 312 Photometric Results
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See also:
II/118 : UBVRI standards around Celestial Equator (Landolt 1983)
I/238 : Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
J/AJ/103/638 : USNO Photographic Parallaxes. I. (Monet+, 1992)
J/A+AS/107/365 : Dwarfs and subdwarfs IR photometry (Alonso+, 1994)
J/AJ/133/2502 : UBVRI Standard Stars (Landolt, 2007)
J/A+A/493/L27 : Parallaxes of 10 ultracool subdwarfs (Schilbach+, 2009)
J/AJ/137/1 : Proper motions and astrometry of late-type dwarfs
(Faherty+, 2009)
J/ApJ/752/56 : BDKP. III. Parallaxes for 70 ultracool dwarfs (Faherty+, 2012)
J/ApJS/201/19 : Hawaii Infrared Parallax Program. I. (Dupuy+, 2012)
J/AJ/146/131 : UBVRI standard stars at +50° declination (Landolt, 2013)
J/AJ/147/94 : Solar neighborhood. XXXII. L and M dwarfs (Dieterich+, 2014)
J/ApJ/784/156 : Parallaxes for 1507 nearby mid-to-late M dwarfs
(Dittmann+, 2014)
J/AJ/151/160 : 1103 parallaxes and proper motions from URAT (Finch+, 2016)
J/AJ/152/24 : Trigonometric parallaxes of 134 low-mass stars
(Weinberger+, 2016)
J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)
J/A+A/598/A92 : New ultracool subdwarfs (Lodieu+, 2017)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
18- 37 A20 --- OName Alternate name
39- 40 I2 h RAh Hour of Right Ascension (J2000) (1)
42- 43 I2 min RAm Minute of Right Ascension (J2000) (1)
45- 49 F5.2 s RAs Second of Right Ascension (J2000) (1)
51 A1 --- DE- Sign of the Declination (J2000) (1)
53- 54 I2 deg DEd Degree of Declination (J2000) (1)
56- 57 I2 arcmin DEm Arcminute of Declination (J2000) (1)
59- 62 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
64 I1 --- Camera [1/3] Camera used for observations (2)
66- 69 A4 --- Filter Filter used for observations (A2-1, ST-R,
I-2, Z-2)
71- 73 I3 --- Nfr [10/360] Number of acceptable CCD frames
75- 77 I3 --- Nights [9/304] Number of separate nights on which
observations were obtained
79- 80 I2 --- Nstars [3/54] Number of reference stars employed
in astrometric solutions
82- 88 F7.2 yr Date1 [1983.19/2013.10] Time coverage
90- 96 F7.2 yr Date2 [1988.87/2017.10] Time coverage
98-102 F5.2 yr Cover [2.07/16.31] Years or coverage
104 A1 -- Type [nru] Astrometry type (3)
106-111 F6.2 mas plxrel [2.29/259.65] Relative parallax
113-116 F4.2 mas e_plxrel [0.19/3.05] Error in plxrel
118-123 F6.1 mas/yr pmrel [2.2/5117.3] Relative proper motion
125-127 F3.1 mas/yr e_pmrel [0.1/2.7] Error in pmrel
129-133 F5.1 deg PArel [1.2/359.1] Position angle of relative proper
motion
135-137 F3.1 deg e_PArel [0.1/7.4] Error in PArel
139-144 F6.2 mas plxabs [2.81/261.12] Absolute parallax
146-149 F4.2 mas e_plxabs [0.19/3.05] Error in plxabs
151-155 F5.1 km/s Vtan [2.3/608.3] Tangential velocity
157-161 F5.1 km/s e_Vtan [0/111.2] Error in Vtan
163-165 A3 --- Note Note(s) (4)
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Note (1): Coordinates are from the 2MASS catalog (Cat. II/246) when available,
else from Gaia Data Release 1 (Cat. I/337), propagated to epoch J2000
using proper motions presented here.
Note (2): Camera used for observations as follows:
1 = TI800;
2 = TEK2K;
3 = EEV24.
Note (3): Astrometry type as follows:
n = New results (previously unpublished);
u = Update of previously published results, using additional observations;
r = Revision of previously published results using parallax factors with
respect to the solar system barycenter and revised corrections from
relative to absolute parallax.
Note (4): Note as follows:
1 = Previous astrometric results were published in Dahn et al.
(2002AJ....124.1170D 2002AJ....124.1170D). Results presented here arise from updated reduction
methods and may include additional data, thus, they supercede the results
of Dahn et al. (2002AJ....124.1170D 2002AJ....124.1170D);
2 = Previous astrometric results were published in Monet et al. (1992,
J/AJ/103/638). Results presented here arise from updated reduction methods
and may include additional data, thus, they supercede the results of
Monet et al. (1992, J/AJ/103/638);
3 = Object is a field reference star for LHS 3259 for which there were
measurable astrometric results. It was named LHS 3259.1 in Monet et al.
(1992, J/AJ/103/638);
4 = Object is a field reference star for LHS 3548 for which there were
measurable astrometric results. It was named LHS 3548.1 in Monet et al.
(1992, J/AJ/103/638).
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
18- 23 F6.2 mas plxabs [4.6/261.12] Absolute parallax
25- 29 F5.2 mas e_plxabs [0.18/12.5] Error in plxabs
31- 36 F6.1 mas/yr pmrel [10.3/5124.3] Relative proper motion
38- 41 F4.1 mas/yr e_pmrel [0.1/29.3]? Error in pmrel
43- 47 F5.1 deg PArel [6.3/348.9] Position angle of relative proper
motion
49- 51 F3.1 deg e_PArel [0/4.2]? Error in PArel
53- 54 I2 --- Ref [1/30] Reference (1)
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Note (1): Reference as follows:
1 = This paper, Table 1;
2 = Liu et al. (2016ApJ...833...96L 2016ApJ...833...96L);
3 = Dittmann et al. (2014, J/ApJ/784/156);
4 = Wienberger et al. (2016, J/AJ/152/24);
5 = Wang et al. (2014PASP..126...15W 2014PASP..126...15W);
6 = Faherty et al. (2016, J/ApJS/225/10);
7 = Finch & Zacharias (2016, J/AJ/151/160);
8 = Tinney et al. (1995AJ....110.3014T 1995AJ....110.3014T);
9 = Henry et al. (2006AJ....132.2360H 2006AJ....132.2360H);
10 = Gatewood & Coban (2009AJ....137..402G 2009AJ....137..402G);
11 = Costa et al (2005AJ....130..337C 2005AJ....130..337C);
12 = Jao et al. (2011AJ....141..117J 2011AJ....141..117J);
13 = Zapatero Osorio et al. (2014A&A...568A...6Z 2014A&A...568A...6Z);
14 = van Altena et al. (1995gcts.book.....V 1995gcts.book.....V, Vol. I, Cat. I/238);
15 = Dieterich et al. (2014, J/AJ/147/94);
16 = Vrba et al. (2004AJ....127.2948V 2004AJ....127.2948V);
17 = Dupuy & Liu (2012, J/ApJS/201/19);
18 = Smart et al. (2010A&A...514A..84S 2010A&A...514A..84S);
19 = Khovritchev et al. (2013MNRAS.435.1083K 2013MNRAS.435.1083K);
20 = Andrei et al. (2011AJ....141...54A 2011AJ....141...54A);
21 = Smart et al. (2007A&A...464..787S 2007A&A...464..787S);
22 = Schilbach et al. (2009, J/A+A/493/L27);
23 = Jao et al. (2005AJ....129.1954J 2005AJ....129.1954J);
24 = Tinney et al. (1996MNRAS.281..644T 1996MNRAS.281..644T);
25 = Costa et al. (2006AJ....132.1234C 2006AJ....132.1234C);
26 = MacConnell et al. (1997AJ....114.1268M 1997AJ....114.1268M);
27 = Faherty et al. (2012, J/ApJ/752/56);
28 = Reidel et al. (2010AJ....140..897R 2010AJ....140..897R);
29 = Gawronski et al. (2017MNRAS.466.4211G 2017MNRAS.466.4211G);
30 = Pravdo & Shaklan (2009ApJ...700..623P 2009ApJ...700..623P).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Name (1)
18- 22 F5.2 mag Vmag [11.33/22.65]? Johnson V band magnitude
24- 27 F4.2 mag e_Vmag [0.01/0.3]? Error in Vmag
29- 33 F5.2 mag Imag [9.59/20.6]? Cousins I band magnitude
35- 38 F4.2 mag e_Imag [0.01/0.5]? Error in Imag
39 A1 --- u_Imag [:] Uncertainty flag in Imag
41- 45 F5.2 mag Jmag [8.39/16.47]? 2MASS J band magnitude
47- 50 F4.2 mag e_Jmag [0.02/0.12]? Error in Jmag
52- 56 F5.2 mag Hmag [7.88/15.78]? 2MASS H band magnitude
58- 61 F4.2 mag e_Hmag [0.02/0.14]? Error in Hmag
63- 67 F5.2 mag Ksmag [7.59/15.62]? 2MASS Ks band magnitude
69- 72 F4.2 mag e_Ksmag [0.01/0.22]? Error in Ksmag
74- 84 A11 --- SpType Spectral type
86- 90 A5 --- Type Adopted stellar type (2)
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Note (1): Name corresponds to the 2MASS J identifier in all but five cases where
the LHS name is used.
Note (2): Our adopted types are as follows:
1 = K or M Dwarf;
2 = An uncertain subdwarf with 150=<Vtan<180 km/s and/or showing marginal
subluminosity in one or more of the diagrams presented in Section 5;
3 = K or M subdwarf (but not extreme nor ultra);
4 = Exteme M subdwarf (esdM);
5 = Ultra M subdwarf (usdM);
6 = L or T dwarf (d);
7 = L subdwarf (sdL).
Type assignments for 3-7 are based on observed spectroscopic classifications
found in the literature. For types 2 and 3, a following letter indicates the
supporting evidence for our typing decision where:
v = Vtan≥180 km/s;
s = Spectral type;
l = Significant subluminosity in one or more of color-absolute magnitude
diagrams presented in Section 5 of the paper.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 14-Jun-2018