J/MNRAS/400/317 IC 4665 low-mass members (Jeffries+, 2009)
Low-mass members of the young cluster IC 4665 and pre-main-sequence
lithium depletion.
Jeffries R.D., Jackson R.J., James D.J., Cargile P.A.
<Mon. Not. R. Astron. Soc., 400, 317-329 (2009)>
=2009MNRAS.400..317J 2009MNRAS.400..317J
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; Radial velocities ;
Equivalent widths
Keywords: stars: pre-main-sequence -
open clusters and associations: individual: IC 4665
Abstract:
We have used fibre spectroscopy to establish cluster membership and
examine pre-main-sequence (PMS) lithium depletion for low-mass stars
(spectral types F to M) in the sparse young (∼30Myr) cluster
IC 4665. We present a filtered candidate list of 40 stars that should
contain 75 per cent of single cluster members with 11.5<V<18 in the
central square degree of the cluster. Whilst F- and G-type stars in IC
4665 have depleted little or no lithium, the K- and early M-type stars
have depleted more Li than expected when compared with similar stars
in other clusters of known age. An empirical age estimate based on Li
depletion among the late-type stars of IC 4665 would suggest that it
is older than 100Myr.
Description:
Spectroscopic observations of candidate low-mass stars in IC 4665,
with 11.5<V<18 and 0.4<V-I<3, were conducted on the nights beginning
2008 June 8 and 9, using the AF2/WYFFOS multifibre spectrograph at a
Nasmyth focus of the 4.2-m William Herschel Telescope (WHT).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 168 452 The spectroscopic measurements of 452 photometric
candidates in IC 4665
table2.dat 86 56 Properties of candidate RV members of IC 4665
table3.dat 37 44 Lithium abundances in IC 4665
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See also:
II/194 : Photometric study of IC 4665 (McCarthy+ 1969)
J/AJ/105/1441 : IC 4665 (Prosser 1993)
J/AJ/106/637 : ICCD speckle observations. IX (Mason+, 1993)
J/A+A/448/189 : IzJHK photometry of IC4665 (de Wit+, 2006)
J/A+A/479/141 : Iz photometry, RV and EW(Li) in IC 4665 (Manzi+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [JCO]
4- 8 A5 --- Name Name (N_NNN)
10- 18 F9.5 deg RAdeg Right ascension in decimal degrees (J2000)
20- 26 F7.5 deg DEdeg Declination in decimal degrees (J2000)
28- 33 F6.3 mag Vmag AF2/WYFFOS V magnitude
35- 39 F5.3 mag V-I AF2/WYFFOS V-I colour index
41 I1 --- Nobs Number of observations for radial velocities
43- 48 F6.3 d HJD1 ? Measurement 1, HJD-2454600
50- 55 F6.1 km/s HRV1 ? Measurement 1 heliocentric radial velocity
57- 60 F4.1 km/s e_HRV1 ? rms uncertainty on RV1
62- 67 F6.3 d HJD2 ? Measurement 2, HJD-2454600
69- 74 F6.1 km/s HRV2 ? Measurement 2 heliocentric radial velocity
76- 78 F3.1 km/s e_HRV2 ? rms uncertainty on RV2
80- 85 F6.3 d HJD3 ? Measurement 3, HJD-2454600
87- 92 F6.1 km/s HRV3 ? Measurement 3 heliocentric radial velocity
94- 96 F3.1 km/s e_HRV3 ? rms uncertainty on RV3
98-103 F6.3 d HJD4 ? Measurement 4, HJD-2454600
105-109 F5.1 km/s HRV4 ? Measurement 4 heliocentric radial velocity
111-113 F3.1 km/s e_HRV4 ? rms uncertainty on RV4
115-121 F7.1 km/s HRV ?=-9999.0 Mean heliocentric radial velocity
123-126 F4.1 km/s e_HRV ?=99.0 rms uncertainty on RV
128-130 I3 --- SNR Signal-to-noise ratio of the averaged spectrum
132-134 I3 0.1pm EWLi ? Measured Li equivalent width
136-138 I3 0.1pm e_EWLi ?=-99 rms uncertainty on EWLi
140-146 F7.1 km/s vsini ?=-9999.0 Rotational velocity
148-154 F7.1 km/s e_vsini ?=-9999.0 rms uncertainty on vsini
156 I1 --- Var [0/2]? RV variability flag (0=not variable) (1)
158 I1 --- CCF [0/2]? Cross-correlation function with the
template standard star shows evidence for
more than one star (1=evidence of binarity)
160-162 I3 --- P93 ? Prosser et al., 1993, Cat. J/AJ/105/1441
<Cl* IC 4665 P NNN> in Simbad
164-168 I5 --- M08 ? Manzi et al., 2008, Cat. J/A+A/479/141
<Cl* IC 4665 MRD NNN> in Simbad
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Note (1): RV variability flag as follows:
1 = variable at >99.9 per cent confidence
0 = not variable
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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- 3 A3 --- --- [JCO]
4- 8 A5 --- Name Name (N_NNN)
10- 14 F5.2 mag Vmag AF2/WYFFOS V magnitude
16- 19 F4.2 mag V-I AF2/WYFFOS V-I colour index
21- 23 I3 0.1pm EWLi Lithium equivalent width
25- 27 I3 0.1pm e_EWLi ?=-99 rms uncertainty on EWLi (1)
29- 33 F5.1 km/s RV Radial velocity
35- 37 F3.1 km/s e_RV rms uncertainty on RV
39- 42 F4.1 km/s vsini Rotational velocity
44- 48 F5.1 km/s e_vsini ?=-99.9 rms uncertainty on vsini (1)
50- 54 F5.2 0.1nm EWHa Hα equivalent width (positive=emission)
56- 59 F4.2 0.1nm EWCaI1 Equivalent width of the
gravity-sensitive [CaI] 6439Å line
61- 64 F4.2 0.1nm EWCaI2 Equivalent width of the
gravity-sensitive [CaI] 6463Å line
66- 70 F5.1 mas/yr pmRA ? Proper motion along right ascension
(from NOMAD catalog, Cat. I/297)
72- 74 F3.1 mas/yr e_pmRA ? rms uncertainty on RA
76- 80 F5.1 mas/yr pmDE ? Proper motion along declination
(from NOMAD catalog, Cat. I/297)
82- 84 F3.1 mas/yr e_pmDE ? rms uncertainty on pmDE
86 A1 --- Mm [Y/N?] Final assessment of membership flag
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Note (1): An uncertainty on -99 or -99.9 indicates an upper limit.
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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- 3 A3 --- --- [JCO]
4- 8 A5 --- Name Name (N_NNN)
10- 14 F5.3 mag V-I AF2/WYFFOS V-I colour index
16- 19 I4 K Teff Effective temperature
21 A1 --- l_A(Li)LTE Limit flag on A(Li)LTE
22- 26 F5.2 mag A(Li)LTE ? LTE Li abundance, A(Li)=12+log[N(Li)/N(H)]
28- 31 F4.2 mag e_A(Li)LTE ? rms uncertainty on A(Li)LTE
33 A1 --- l_A(Li)NLTE Limit flag on A(Li)NLTE
34- 37 F4.2 mag A(Li)NLTE ? NLTE Li abundance, A(Li)=12+log[N(Li)/N(H)],
for stars with Teff>4500K
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 17-Sep-2010