J/MNRAS/396/2061 Equivalent widths of EP UMA (HR 4330) (Sriraghavan+, 2009)
Search for rapid spectral feature variations in chemically peculiar star HR4330.
Sriraghavan S.M., Babu G.S.D.
<Mon. Not. R. Astron. Soc., 396, 2061-2064 (2009)>
=2009MNRAS.396.2061S 2009MNRAS.396.2061S
ADC_Keywords: Stars, peculiar ; Equivalent widths
Keywords: diffusion - stars: individual: HR 4330
Abstract:
The chemically peculiar star HR 4330 (=HD 96707, EP UMa) was observed
using the 2-m Himalayan Chandra Telescope at the Indian Astronomical
Observatory, Hanle, India, for studying the variations in its spectral
features. It was found that the spectral features of CaII 3933Å and
SrII 4077Å were showing rapid variations in their equivalent widths
with a periodicity of 0.28±0.02d. Such short-term variations suggest
that there could be a dynamically active surface with rapid variation
in the conditions of the stellar atmosphere.
Description:
A total of 438 spectrograms were obtained spread over three different
observing nights with 7h on the night of 2006 March 18, 7h on the
night of 2007 March 27 and 8h on the night of 2007 March 28.
Objects:
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RA (2000) DE Designation(s)
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11 09 39.8 +67 12 37 HR4330 = V* EP UMa
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 29 438 Equivalent widths of CaII 3933 and SrII 4077
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See also:
J/A+AS/136/379 : uvby photometry of 4 CP stars (Adelman+ 1999)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 F11.3 d JD Julian date of observations (1)
13- 19 F7.2 --- SNR Signal-to-noise ratio
21- 24 F4.2 0.1nm EW3933 Equivalent width at CaII 3933Å
26- 29 F4.2 0.1nm EW4077 Equivalent width at SrII 4077Å
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Note (1): Observations on 18 March 2006 (JD=2453813), 27 March 2007
(JD=2454187) and 28 March 2007 (JD=2454188).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Oct-2009