J/AJ/121/1040 PMS members of upper Scorpius OB association (Preibisch+, 2001)
A large spectroscopic survey for young low-mass members of the
upper Scorpius OB association.
Preibisch T., Guenther E., Zinnecker H.
<Astron. J. 121, 1040 (2001)>
=2001AJ....121.1040P 2001AJ....121.1040P
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; Equivalent widths
Keywords: open clusters and associations: individual (Scorpius-Centaurus) -
stars: mass function - stars: pre-main-sequence
Abstract:
We present the results of a large intermediate-resolution
spectroscopic survey for pre-main-sequence (PMS) stars in the Upper
Scorpius OB association, the nearest region of recent massive star
formation. Utilizing the 2dF multiobject spectrograph at the
Anglo-Australian Telescope, we obtained spectra of 576 stars with
magnitudes 12.5≤R≤16.5 in a 6°2 area in Upper Scorpius. Among
these objects we were able to identify 98 new PMS stars, nearly all of
them M-type stars, by their strong lithium absorption lines. We place
the new PMS stars into the H-R diagram and find that their ages agree
well with the mean age of 5Myr determined in our earlier investigation
based on a smaller sample of stars. The number of low-mass
(0.1M☉≲M*≲0.5M_☉) members is at least as high as expected
from the known number of high-mass (M*≳3M☉) association members
and from recent determinations of the field star initial mass
function. Thus, there is no deficit of low-mass stars in Upper
Scorpius.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 38 100 Li-rich stars in Upper Scorpius detected in
our 2dF survey
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See also:
J/A+A/333/619 : Upper Scorpius OB association Lithium survey (Preibisch+ 1998)
J/AJ/124/404 : Upper Scorpius OB association Lithium survey. II.
(Preibisch, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- 2dF [2dF]
4- 18 A15 --- [PGZ2001] Star name (1)
20- 23 F4.2 0.1nm EWLi Li 6708Å equivalent width (in Å)
24 A1 --- u_EWLi Uncertainty flag on EWLi
26- 30 F5.1 0.1nm EWHa Hα equivalent width (in Å)
31 A1 --- u_EWHa Uncertainty flag on EWHa
33- 35 A3 --- SpType Spectral type
36 A1 --- u_SpType Uncertainty flag on SpType
38 A1 --- f_[PGZ2001] Flag on [PGZ2001] (2)
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Note (1): Position coordinates in [PGZ2001] are in a HHMMSS.s-DDMMSS format.
In Simbad, the are identified as [PGZ2001] JHHMMSS.s-DDMMSS
Note (2): Star with a strongly veiled spectrum. Object might be identical
to RXJ 1614.3-1906b from Martin et al. (1998AJ....115..351M 1998AJ....115..351M)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 07-Oct-2002