J/MNRAS/409/582 Helium-rich subluminous B stars abundances (Naslim+, 2010)
Abundance analyses of helium-rich subluminous B stars.
Naslim N., Jeffery C.S., Ahmad A., Behara N.T., Sahin T.
<Mon. Not. R. Astron. Soc., 409, 582-590 (2010)>
=2010MNRAS.409..582N 2010MNRAS.409..582N
ADC_Keywords: Stars, peculiar ; Abundances ; Equivalent widths
Keywords: stars: abundances - stars: chemically peculiar - stars: early-type -
stars: evolution - subdwarfs
Abstract:
The connection between helium-rich hot subdwarfs of spectral types O
and B (He-sdB) has been relatively unexplored since the latter were
found in significant numbers in the 1980s. In order to explore this
connection further, we have analysed the surface composition of six
He-sdB stars, including LB 1766, LB 3229, SB 21 (= Ton-S 137 =
BPS CS 29503-0009), BPS CS 22940-0009, BPS CS 29496-0010 and
BPS CS 22956-0094.
Description:
Spectra of several hydrogen-deficient stars were obtained with the
University College London Echelle Spectrograph on the Anglo-Australian
Telescope (AAT) in 2005 August.
Objects:
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RA (2000) DE Designation(s)
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04 59 24. -53 53 LB 1766 = uvby98 600001766
00 04 31.0 -24 26 21 SB 21 = BPS CS 29503-0009
20 30 20.0 -59 50 50 BPS CS 22940-0009 = BPS CS 22940-0009
23 34 02.0 -28 51 38 BPS CS 29496-0010 = PHL 561
22 16 56.4 -64 31 51 BPS CS 22956-0094 = BPS CS 22956-0094
01 47 17.5 -51 33 39 LB 3229 = JL 261
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 53 254 Oscillator strength, measured equivalent width
and derived elemental abundance for each line
measured in the six programme stars
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Star name
19- 25 A7 --- Ion Ion name
27- 33 F7.2 0.1nm lambda Wavelength
35 A1 --- n_lambda [2/3] Note (1)
37- 42 F6.3 [-] loggf ? Oscillator strength value (2)
44 A1 --- n_loggf [1ce] Note (1)
46- 48 I3 0.1nm EW ? Equivalent width
50- 53 F4.2 [---] eps ? Elemental abundance (log(Ion/H)+12)
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Note (1): Notes as follows:
1 = empirical oscillator strength to match observed line; not used in mean
2 = blended with NII; not used in mean, except for LB 3229 where NII is weak
3 = possibly blended; not used in mean
e = linked with following wavelength with "c" note
c = linked with preceding wavelength with "e" note
Note (2): References for gf values (not explicited in the paper):
CII = Yan et al. (1987)
CIII = Hibbert (1976); Hardorp & Scholz (1970); Bockasten (1955)
NII = Becker & Butler (1990)
NIII = Butler (1984)
OII = Becker & Butler (1988)
NeII = Wiese et al. (1966)
SiIII = Becker & Butler (1989); Hardorp & Scholz (1970)
SiIV = Becker & Butler (1989); Kurucz & Petryemann (1975),
MgII = Wiese et al. (1966)
OII = Becker & Butler (1988)
AlIII = Canuto, & Mendoza (1969); McEachran & Cohen (1983)
SIII = Wiese et al. (1969); Hardorp & Scholz (1970)
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Table A2: Abundance errors δeps due to errors in Teff and logg.
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C N O Ne Mg Al Si S
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BPS CS 22940-0009
δTeff=1000K +0.03 +0.06 +0.11 +0.05 +0.08 +0.10 +0.08 +0.14
δlogg=0.2 +0.008 +0.004 -0.02 +0.01 -0.03 -0.02 +0.02 -0.02
LB 1766
δTeff=1000K -0.07 +0.09 +0.11 +0.05 +0.08 +0.09 +0.10 +0.14
δlogg=0.2 +0.10 +0.004 -0.03 +0.008 -0.04 -0.04 -0.02 -0.03
LB 3229
δTeff=1000K +0.10 +0.16 +0.17 +0.19 +0.11
δlogg=0.2 -0.04 -0.09 -0.10 -0.12 -0.04
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 06-May-2011