J/MNRAS/417/495 HD 32115 and HD 37594 atmospheric parameters (Fossati+, 2011)
The accuracy of stellar atmospheric parameter determinations:
a case study with HD 32115 and HD 37594.
Fossati L., Ryabchikova T., Shulyak D.V., Haswell C.A., Elmasli A.,
Pandey C.P., Barnes T.G., Zwintz K.
<Mon. Not. R. Astron. Soc., 417, 495-507 (2011)>
=2011MNRAS.417..495F 2011MNRAS.417..495F
ADC_Keywords: Stars, A-type ; Abundances
Keywords: techniques: spectroscopic - stars: fundamental parameters -
stars: individual: HD 32115 - stars: individual: HD 37594 -
stars: individual: HD 49933
Abstract:
We present detailed parameter determinations of two chemically normal
late A-type stars, HD 32115 and HD 37594, to uncover the reasons
behind large discrepancies between two previous analyses of these
stars performed with a semi-automatic procedure and a 'classical'
analysis. Our study is based on high-resolution, high signal-to-noise
ratio spectra obtained at the McDonald Observatory. Our method is
based on the simultaneous use of all available observables:
multicolour photometry, pressure-sensitive magnesium lines, metallic
lines and Balmer line profiles. Our final set of fundamental
parameters fits, within the error bars, all available observables.
It differs from the published results obtained with a semi-automatic
procedure.
Description:
Spectra of HD 32115 and of HD 37594 were obtained on 2010 November 30
with the Robert G. Tull Coude Spectrograph (TS) attached at the 2.7-m
telescope of McDonald Observatory. This is a cross-dispersed echelle
spectrograph yielding a resolving power (R) of 60000 for the
configuration used here. The signal-to-noise ratio (S/N) per pixel at
λ∼5000Å is 490 and 535, respectively for HD 32115 and
HD 37594.
Objects:
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RA (2000) DE Designation(s)
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05 00 39.81 -02 03 57.7 HD 32115 = HR 1613
05 39 31.15 -03 33 52.9 HD 37594 = HR 1940
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 68 241 Lines used for the parameter determination
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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- 4 A4 --- Ion Element and ionisation stage
6 A1 --- n_Ion [ab] For CrII, results obtained with two
different sets of loggf
9- 17 F9.4 0.1nm lambda Wavelength (1)
19- 24 F6.4 eV ExP Excitation potential (1)
26- 31 F6.3 [-] loggf Oscillator strength (2)
33 A1 --- n_W(37594) [S] Note on W(37594) (3)
35- 40 F6.2 0.1pm W(37594) ? HD 37594 equivalent width (mÅ)
42- 46 F5.2 [-] A(37594) ? HD 37594 abundance (5)
48 A1 --- n_W(32115) [S] Note on W(32115) (3)
50- 55 F6.2 0.1pm W(32115) ? HD 32115 equivalent width (mÅ)
57- 61 F5.2 [-] A(32115) ? HD 32115 abundance (5)
63- 68 A6 --- r_loggf Reference for loggf (4)
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Note (1): Wavelengths and excitation potentials are taken from the VALD database
Note (2): The loggf values by Blackwell et al. (1980A&A....81..340B 1980A&A....81..340B) and Baschek
et al. (1970A&A.....4..229B 1970A&A.....4..229B) were corrected by +0.2 and +0.16, respectively.
Note (3): S denotes line abundances determined by fitting the observed line
profile, with the equivalent width determined from the line abundance.
Note (4): References as follows:
BGHR = Baschek et al. (1970A&A.....4..229B 1970A&A.....4..229B)
BHN = Bizzari et al. (1993A&A...273..707B 1993A&A...273..707B)
BK = Bard & Kock (1994A&A...282.1014B 1994A&A...282.1014B)
BKK = Bard et al. (1991A&A...248..315B 1991A&A...248..315B)
BSScor = Blackwell et al. (1980A&A....81..340B 1980A&A....81..340B)
BWL = O'Brian et al. (1991, , J. Opt. Soc. America B, 8, 1185)
FMW = Fuhr et al. (1988, J. Phys. Chemical Reference Data, 17, Cat. VI/72)
HLGN = Hannaford et al. (1992A&A...259..301H 1992A&A...259..301H)
K10 = http://kurucz.harvard.edu/atoms.html
KK = Kroll & Kock (1987A&AS...67..225K 1987A&AS...67..225K)
M = Moity (1983A&AS...52...37M 1983A&AS...52...37M)
MFW = Martin et al. (1988, J. Phys. Chemical Reference Data, 17, Cat. VI/72)
PTP = Pickering et al. (2001ApJS..132..403P 2001ApJS..132..403P)
RHL = Ryabchikova et al. (%R 1994MNRAS.267..697R 1994MNRAS.267..697R)
RU = Raassen & Uylings (1998, Cat. J/A+A/340/300)
S = Smith (1988, , J. Phys. B., 21, 2827)
SLS = Sobeck et al. (2007ApJ...667.1267S 2007ApJ...667.1267S)
Sm = Smith (1981A&A...103..351S 1981A&A...103..351S)
SN = Smith & O'Neil (1975A&A....38....1S 1975A&A....38....1S)
SR = Smith & Raggett (1981, , J. Phys. B, 14, 4015)
T83av = Ryabchikova et al. (1999, , Phys. Scr., T83, 162)
TB = Seaton et al. (1994MNRAS.266..805S 1994MNRAS.266..805S, Cat, VI/80)
Note (5): Abundances A(el)=log(Nel/Ntot) if el=element.
Average abundances and standard deviation, with
the number of lines in parenthesis:
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HD 37594 HD 32115
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CaI -5.92±0.10 (25) -5.71±0.06 (16)
CaII -5.77±0.12 ( 9) -5.64±0.13 ( 7)
TiI -7.35±0.11 ( 7) -7.16±0.06 (10)
TiII -7.25±0.08 (13) -7.09±0.05 (20)
CrI -6.74±0.14 (12) -6.44±0.11 (26)
CrII a -6.43±0.04 ( 9) -6.12±0.07 (10)
CrII b -6.62±0.08 ( 9) -6.31±0.10 (10)
FeI -4.91±0.09 (75) -4.63±0.07 (88)
FeII -4.84±0.10 (32) -4.59±0.08 (35)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Apr-2012