J/ApJ/525/420 UV and optical line variations in ε Persei (Gies+, 1999)
Ultraviolet and optical line profile variations in the spectrum of
ε Persei
Gies D.R., Kambe E., Josephs T.S., Bagnuolo W.G., Choi Y.J., Gudehus D.,
Guyton K.M., Hartkopf W.I., Hildebrand J.L., Kaye A.B., Mason B.D.,
Riddle R.L., Sowers J.W., Turner N.H., Wilson J.W., Xiong Y.
<Astrophys. J. 525, 420 (1999)>
=1999ApJ...525..420G 1999ApJ...525..420G
ADC_Keywords: Binaries, spectroscopic ; Spectra, ultraviolet ; Spectroscopy ;
Stars, early-type ; Stars, variable
Mission_Name: IUE
Keywords: binaries: spectroscopic - stars: early-type - stars: individual
(ε Persei) - stars: oscillations - stars: winds,
outflows - ultraviolet: stars
Abstract:
The rapid variable star, ε Per (B0.5 IV-III), displays the
largest amplitude profile fluctuations known among the growing number
of massive, spectrum-variable stars. Here we present an analysis of a
continuous 5 day run of IUE UV spectroscopy, and we show for the first
time that the systematic, blue-to-red moving patterns observed in
high-quality optical spectra are also present in the UV photospheric
lines. We present cross-correlation functions of the individual
spectra with that of a narrow-lined standard that produce a high
signal-to-noise ratio representation of the blue-to-red moving bump
patterns found in individual lines. We then use time series analysis
methods to determine the periodic components of the profile variations
(after reregistering the spectra to correct for binary motion). There
are at least six periods present (ranging from 8.46 to 2.27 hr), and
most of these signals are also found in optical line variations
observed in 1986 (although the relative amplitudes have changed
significantly). Furthermore, analysis of a shorter time series of IUE
spectra from 1984 shows that similar periods were present then. We
also present Hα and He I 6678 profiles obtained with the Georgia
State University Multi-Telescope Telescope, which were made
simultaneously with IUE, and we show that the profile variations are
essentially identical in the UV and optical ranges.
Objects:
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RA (2000) DE Designation(s)
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03 57 51.2 +40 00 37 Eps Per = HD 24760 = SAO 56840 = HIP 18532
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 24 181 International Ultraviolet Explorer radial
velocity measurements
table2.dat 31 54 Multi-Telescope Telescope radial velocity
measurements
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- SWP The IUE SWP camera image number
7- 18 F12.4 d JD Julian date
21- 24 F4.1 km/s Vr Final radial velocity
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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- 11 F11.3 d JD Julian date
13- 17 F5.1 km/s Valpha Radial velocity of Hα
20- 24 F5.1 km/s VHeI Radial velocity of He I 6678Å
27- 31 F5.1 km/s Vr Final mean radial velocity
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History:
From ApJ electronic edition
(End) Greg Schwarz [AAS] 27-Apr-2000