J/A+A/440/249 The close binary system epsilon Lupi (Uytterhoeven, 2005)
The orbit of the close spectroscopic binary epsilon Lupi and the intrinsic
variability of its early B-type components
Uytterhoeven K., Harmanec P., Telting J.H., Aerts C.
<Astron. Astrophys. 440, 249 (2005)>
=2005A&A...440..249U 2005A&A...440..249U (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, spectroscopic ; Radial velocities
Keywords: stars: binaries: spectroscopic - stars: binaries: close -
stars: oscillations - line: profiles - stars: individual: epsilon Lup
Description:
We subjected 106 new high-resolution spectra of the double-lined
spectroscopic close binary epsilon Lupi, obtained in a time-span of 17
days from two different observatories, to a detailed study of orbital
and intrinsic variations. We derived accurate values of the orbital
parameters. We refined the sidereal orbital period to 4.55970 days and
the eccentricity to e=0.277. By adding old radial velocities, we
discovered the presence of apsidal motion, with a period of the
rotation of apses of about 430 years. Such a value is in agreement
with theoretical expectations. Additional data is needed to confirm
and refine this value. Our dataset did not allow to derive the orbit
of the third body, which is known to orbit the close system in
approximately 64 years. We present the secondary of epsilon Lupi as a
new beta Cephei variable, while the primary is a beta Cephei suspect.
A first detailed analysis of line-profile variations of both primary
and secondary led to the detection of one pulsation frequency near
10.36c/d in the variability of the secondary, while no clear
periodicity was found in the primary, although low-amplitude
periodicities are suspected. The limited accuracy and extent of our
dataset did not allow any further analysis, such as
mode-identification.
Objects:
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RA (2000) DE Designation(s)
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15 22 40.9 -44 41 23 eps Lup = HD 136504
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 41 152 Radial velocities of the primary and secondary of
epsilon Lupi
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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- 12 F12.4 d HJD Heliocentric Julian Date
14- 19 F6.1 km/s RV1 Radial Velocity of the primary
21- 25 F5.1 km/s e_RV1 ? Error Estimate on RV1
27- 32 F6.1 km/s RV2 ? Radial Velocity of the secondary
34- 38 F5.1 km/s e_RV2 ? Error Estimate on RV2
40 A1 --- Note Note (1)
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Note (1): Notes as follows:
A = Campbell and Moore (1928PLicO..16....1C 1928PLicO..16....1C)
B = Buscombe and Morris (1960MNRAS.121..263B 1960MNRAS.121..263B)
C = Thackeray (1970MNRAS.149...75T 1970MNRAS.149...75T)
D = Average of the first moments of the SiIII 4553{Aa} and 4568Å
profiles.
E = Median of the cross-correlation measurements calculated from the
SiIII 4568Å, MgII 4481Å, HeI5016Å, HeI 4917Å,
HeI 5876Å and HeI6678Å profiles.
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Acknowledgements: Katrien Uytterhoeven, katrienu(at)pleione.asu.cas.cz
(End) Patricia Vannier [CDS] 05-May-2005