J/A+A/508/833 SACY III. Li abundances (da Silva+, 2009)
Search for associations containing young stars (SACY).
III. Ages and Li abundances.
da Silva L., Torres C.A.O., de la Reza R., Quast G.R., Melo C.H.F.,
Sterzik M.F.
<Astron. Astrophys., 508, 833-839 (2009)>
=2009A&A...508..833D 2009A&A...508..833D
ADC_Keywords: Associations, stellar ; Abundances ; Equivalent widths
Keywords: stars: abundances - stars: pre-main sequence - stars: late-type -
star: evolution
Abstract:
Our study is a follow-up of the SACY project, an extended high
spectral resolution survey of more than two thousand optical
counterparts to X-ray sources in the southern hemisphere targeted to
search for young nearby association. Nine associations have either
been newly identified, or have had their member list revised. Groups
belonging to the Sco-Cen-Oph complex are not considered in the present
study.
These nine associations, with ages of between about 6Myr and 70Myr,
form an excellent sample to study the Li depletion in the pre-main
sequence (PMS) evolution. In the present paper, we investigate the use
of Li abundances as an independent clock to constrain the PMS
evolution.
Using our measurements of the equivalent widths of the Li resonance
line and assuming fixed metallicities and microturbulence, we
calculated the LTE Li abundances for 376 members of various young
associations. In addition, we considered the effects of their
projected stellar rotation.
Description:
The observations were carried out using the FEROS spectrograph
at la Silla, ESO, and the Coude spectrograph of the 1.62m telescope
of the Observatorio do Pico dos Dias, LNA, Brazil (see Paper I for
details, Torres et al., 2006, Cat. J/A+A/460/695).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables.dat 61 385 Li abundances determined for all high probability
members (tables 3-11 of the paper)
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See also:
J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)
Byte-by-byte Description of file: tables.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Tab [3/11] Table number for association (1)
4- 18 A15 --- Name Star name
20- 21 I2 h RAh Right ascension (J2000)
23- 24 I2 min RAm Right ascension (J2000)
26- 29 F4.1 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 39 I2 arcsec DEs Declination (J2000)
41- 43 I3 0.1pm W(Li) ? Li equivalent width (mÅ)
45- 49 I5 K Teff Effective temperature
51- 55 F5.2 [---] A(Li) ? Li abundance (log[N(Li)/N(H)]+12)
57- 59 I3 km/s vsini ? projected stellar rotational velocity
61 A1 --- Int [I] I for Intruders (Li eliminated stars)
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Note (1): Associations as follows:
3 = β Pictoris association
4 = Tucana-Horologium association
5 = Columba association
6 = Carina association
7 = TW Hydrae association
8 = ε Chamaleontis association
9 = Octans association
10 = Argus association
11 = AB Doradus association
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History:
From electronic version of the journal
References:
Torres et al., Paper I 2006A&A...460..695T 2006A&A...460..695T, Cat. J/A+A/460/695
Almeida Viana et al., Paper II 2009A&A...501..965A 2009A&A...501..965A
(End) Patricia Vannier [CDS] 19-Aug-2011