J/A+A/542/L32 HD 202850 HeI and SiII spectra (Kraus+, 2012)
Detection of a 1.59h period in the B supergiant star HD 202850.
Kraus M., Tomic S., Oksala M.E., Smole M.
<Astron. Astrophys. 542, L32 (2012)>
=2012A&A...542L..32K 2012A&A...542L..32K
ADC_Keywords: Stars, supergiant ; Stars, OB ; Line Profiles ; Spectroscopy
Keywords: stars: early-type - supergiants - stars: atmospheres -
stars: oscillations - stars: individual: HD 202850
Abstract:
Photospheric lines of B-type supergiants show variability in their
profile shapes. In addition, their widths are much wider than can be
accounted for purely by stellar rotation. This excess broadening is
often referred to as macroturbulence. Both effects have been linked to
stellar oscillations, but B supergiants have not been systematically
searched yet for the presence of especially short-term variability
caused by stellar pulsations.
We have started an observational campaign to investigate the line
profile variability of photospheric lines in a sample of Galactic B
supergiants. These observations aim to improve our understanding of
the physical effects acting in the atmospheres of evolved massive
stars.
Description:
A total of 65 optical spectra have been taken within 4 observing
nights covering the photospheric SiII (6347Å & 6371Å) and HeI
6678Å lines. The data were reduced and telluric and heliocentric
velocity corrected. The data files are split into one part covering
the two SiII lines and one part covering the HeI line.
Objects:
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RA (2000) DE Designation(s)
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21 17 24.9 +39 23 41 HD 202850 = HR 8143
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 33 130 List of spectra
spectra/* . 130 Individual spectra
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- FileName Name of the spectrum file in
subdirectory spectra
15- 22 A8 --- Line Line name (HeI 6678 or SiII) (1)
24- 33 A10 "YYYY/MM/DD" Date Observation date
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Note (1): 16 spectra on 2010/09/06, 7 on 2010/09/11, 19 on 2010/09/12 and
23 on 2012/04/30.
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Byte-by-byte Description of file: spectra/*
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Bytes Format Units Label Explanations
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1- 9 F9.4 0.1nm lambda Wavelength (Å)
12- 20 F9.7 -- NFlux Normalized flux
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Acknowledgements:
Michaela Kraus, kraus(at)sunstel.asu.cas.cz
(End) Michaela Kraus [Ondrejov Ob.], Patricia Vannier [CDS] 04-Jun-2012