J/AJ/105/226 UMa Group (Soderblom+ 1993)
Stellar kinematic groups. I. The Ursa Major Group
SODERBLOM D.R., MAYOR M.
<Astron. J. 105, 226 (1993)>
=1993AJ....105..226S 1993AJ....105..226S
ADC_Keywords: Populations, stellar; Combined data; Astrometric data; Space
velocities; Spectral types; Colors; Spectroscopy;Equivalent widths
Abstract:
The Ursa Major Group (UMaG) is studied as a test case for the
authenticity of Stellar Kinematic Groups, using Coravel radial
velocities, recent compilations of astrometric data and new
spectroscopic observations. Spectroscopic age indicators, particularly
indices of the strength of chromospheric emission, are applied to
solar-type candidate members of UMaG, and it is shown that stars that
meet the spectroscopic criteria also have kinematics that agree better
with the space motions of the nucleus of UMaG than does the starting
sample as a whole. The primary limitation on the precision of
kinematics is now parallaxes instead of radial velocities. These more
restrictive kinematic criteria are then applied to other UMaG
candidates and a list summarizing membership is presented. UMaG is
also examined as a cluster, confirming its traditional age of 0.3 Gyr
and a mean [Fe/H] of -0.08 ± 0.09 for those stars most likely to be
bona fide members.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 76 14 Stellar kinematic groups
table3 68 35 Echelle spectroscopy of UMaG candidates
table5 99 46 Spectroscopic membership indicators for UMaG
solar-type stars
table7 112 40 Kinematics of UMaG solar-type candidates
table10 81 27 Kinematics of additional UMaG candidates
table11 76 43 Summary of UMaG membership
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Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 32 A32 --- Name Group name
34- 37 I4 km/s U U space velocity
39- 42 I4 km/s V V space velocity
45- 47 I3 km/s W W space velocity
50- 76 A27 --- Ref References
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Byte-by-byte Description of file: table3
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD Henry Draper number
7- 8 A2 --- m_HD Multiplicity index on HD number
11 A1 --- l_vsini limit flag on vsini
12- 15 F4.1 km/s vsini []? Rotational velocity
17 A1 --- l_WHalpha Limit flag on Walpha
18- 21 F4.2 0.1pm WHalpha []? Equivalent width of Halpha line
23 A1 --- l_W8498 Limit flag on W8498
24- 27 F4.2 0.1pm W8498 []? Equivalent width of 8498A feature
29 A1 --- l_W8542 Limit flag on W8542
30- 33 F4.2 0.1pm W8542 []? Equivalent width of 8542A feature
35 A1 --- l_W8662 Limit flag on W8662
36- 39 F4.2 0.1pm W8662 Equivalent width of 8662A feature
42 A1 --- l_RHalpha Limit flag on RHalpha
43- 47 F5.2 --- log(RHalpha) []? Chromospheric flux ratio (stellar surface
flux divided by bolometric flux) for Halpha
48 A1 --- u_RHalpha Uncertainty flag (only for star HD 141003B)
49 A1 --- l_R8498 Limit flag on R8498
50- 54 F5.2 --- log(R8498) []? Chromospheric flux ratio for 8498A feature
56 A1 --- l_R8542 Limit flag on R8542
57- 61 F5.2 --- log(R8542) []? Chromospheric flux ratio for 8542A feature
63 A1 --- l_R8662 Limit flag on R8662
64- 68 F5.2 --- log(R8662) Chromospheric flux ratio for 8662A feature
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Byte-by-byte Description of file: table5
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Bytes Format Units Label Explanations
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1 A1 --- Member [abc] a: Probable spectroscopic member
b: Possible spectroscopic member
c: Probable spectroscopic non-member
3- 8 A6 --- Wooley Number in catalog of Woolley, et al. (1970)
10- 15 I6 --- HD/HDE Henry Draper number
16- 17 A2 --- m_HD/HDE Multiplicity index on HD or HDE number
19- 22 I4 --- HR []? Harvard Revised (Bright Star) number
23- 24 A2 --- m_HR Multiplicity index on HR number
26- 36 A11 --- Name Other name
38- 41 A4 --- Sp Spectral type (1)
44- 47 F4.2 mag B-V []? (B-V) color from Nicolet (1978) or
Woolley et al. (1970)
48 A1 --- u_B-V uncertainty flag on B-V
50- 53 I4 K Teff []? Effective temperature
54 A1 --- u_Teff uncertainty flag on Teff
56 A1 --- l_R' [<H] limit flag on R'(HK).
An 'H' indicating that Log(R') is instead an
eye estimate of H and K emission strength
from Wilson & Woolley (1970)
57- 61 F5.2 --- logR' []? Chromospheric flux ratio of the
Ca II H and K emission features
62 A1 --- u_logR' uncertainty flag on R'
63 A1 --- n_R(hk) [I] An 'I', indicating logR(hk) is an I(Mg II)
value
64- 68 F5.2 --- logR(hk) []? Rescaled index, the Mg II h and k emission
flux divided by the stellar bolometric flux
and reduced to the scale of the Ca II H and K
emission in logR'
70 A1 --- l_R(TR) limit flag on R(TR)
71- 75 F5.2 --- logR(TR) []? Rescaled index, the emission flux of three
strong features in IUE spectra (N I 1240 A,
Si IV 1400 A, and C IV 1550 A) combined to
produce an index of emission from the star's
transition region (TR), reduced to the scale
of the Ca II H and K lines as above.
77 A1 --- l_R(Halpha) uncertainty flag on R(Halpha)
78- 82 F5.2 --- logR(Halpha) []? Rescaled index, logR(Halpha).
83 A1 --- u_R(Halpha) rms uncertainty on R(Halpha)
84 A1 --- l_R(IRT) uncertainty flag on R(IRT)
85- 89 F5.2 --- logR(IRT) []? Rescaled index, for the Ca II infrared
triplet.
91 A1 --- l_vsini limit flag on vsini
92- 95 F4.1 km/s vsini []? Rotational velocity
97- 99 F3.1 km/s e_vsini []? rms uncertainty in v sin i
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Note (1):
Spectral type from the Bright Star Catalog (Hoffleit & Jaschek 1982),
Levato & Abt (1978), Hoffleit et al. (1983),
and Woolley, et al. (1970)
except for HD 26913/23 (see notes in printed paper).
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Byte-by-byte Description of file: table7 table10
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD Henry Draper number
7- 8 A2 --- m_HD Multiplicity index on HD number
9- 13 F5.1 mas plx Parallax from the latest Yale Parallax
Catalog (van Altena et al. 1992)
15- 18 F4.1 mas e_plx []? rms uncertainty on plx
20- 23 I4 mas/yr pmRA Proper motion in right ascension from the
Catalog of Positons and Proper Motions
(PPM, Roeser & Bastian 1989)
25- 28 F4.1 mas/yr e_pmRA rms uncertainty on pmRA
30- 34 I5 mas/yr pmDE Proper motion in declination from the PPM
36- 38 F3.1 mas/yr e_PMDE rms uncertainty on pmDE
41- 45 F5.1 km/s RV []? Radial velocity from Evans (1980)
47- 49 F3.1 km/s e_RV []? rms uncertainty on RV
52- 56 F5.1 km/s U []? Resultant U component of space motion
58- 61 F4.1 km/s e_U []? rms uncertainty on U
63- 67 F5.1 km/s V []? Resultant V component of space motion
69- 71 F3.1 km/s e_V []? rms uncertainty on V
73- 77 F5.1 km/s W []? Resultant W component of space motion
79- 81 F3.1 km/s e_W []? rms uncertainty on W
84- 88 F5.1 mas plx2 []? Parallax the star must have if V is forced
to a value of +2.0 km/s, given its observed
radial velocity RV (table7 only)
90- 94 F5.2 mag MV2 []? Absolute visual magnitude that follows
from the parallax plx2 (table7 only)
96-100 F5.1 km/s RV2 []? Radial velocity that results if the
parallax is held fixed and the space motion
V is forced to +2.0 km/s (table7 only)
102-106 F5.1 km/s U2 []? U space velocity derived from using the
observed radial velocity RV2 and the
parallax plx2 (table7 only)
108-112 F5.1 km/s W2 []? W space velocity derived from using the
observed radial velocity RV2 and the
parallax plx2 (table7 only)
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Byte-by-byte Description of file: table11
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Bytes Format Units Label Explanations
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1 A1 --- Member + = Probable Members, ? = Possible Members (1)
4- 9 I6 --- HD Henry Draper number
10- 11 A2 --- m_HD Multiplicity index on HD number
13- 16 I4 --- HR []? Harvard Revised number
17 A1 --- m_HR Multiplicity index on HR number
20- 32 A13 --- Name Other name
35- 42 A8 --- Sp Spectral type
44- 48 F5.2 mag B-V (B-V) color
51- 54 I4 K Teff Effective temperature
56- 60 F5.2 mag Mv Absolute visual magnitude
63- 76 A14 --- Rem Remarks
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Note (1):
+: Probable Members: These are stars for which every indicator supports UMaG
membership, which includes:
(1) The stars of the nucleus.
(2) The probable spectroscopic member stars of Table 5, with Xi Boo
excluded.
(3) Other stars, such as Sirius, that have well-defined space motions
that agree (to within one standard deviation) with the mean motion
of the nucleus.
?: Possible Members: In these cases the 3-sigma error ellipsoid overlaps the
mean motion of the nucleus. The possible spectroscopic member stars of
Table5 that have kinematics in accord with the nucleus are included here.
Probable Nonmembers: Any star not listed in Table 11 has been rejected as
a UMaG member.
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Origin: AAS CD-ROM series, Volume 1, 1993
(End) Patricia Bauer [CDS] 06-Jul-1994