J/MNRAS/430/2018 6 bright Galactic Cepheids data (Szabados+, 2013)
Discovery of the spectroscopic binary nature of six southern Cepheids.
Szabados L., Derekas A., Kiss L.L., Kovacs J., Anderson R.I., Kiss CS.,
Szalai T., Szekely P., Christiansen J.L.
<Mon. Not. R. Astron. Soc., 430, 2018-2028 (2013)>
=2013MNRAS.430.2018S 2013MNRAS.430.2018S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Binaries, spectroscopic ; Radial velocities
Keywords: binaries: spectroscopic - stars: variables: Cepheids
Abstract:
We present the analysis of photometric and spectroscopic data of six
bright Galactic Cepheids: GH Carinae, V419 Centauri, V898 Centauri,
AD Puppis, AY Sagittarii and ST Velorum. Based on new radial velocity
data (in some cases supplemented with earlier data available in the
literature), these Cepheids have been found to be members in
spectroscopic binary systems. V898 Cen turned out to have one of the
largest orbital radial velocity amplitude (>40km/s) among the known
binary Cepheids. The data are insufficient to determine the orbital
periods nor other orbital elements for these new spectroscopic
binaries.
These discoveries corroborate the statement on the high frequency of
occurrence of binaries among the classical Cepheids, a fact to be
taken into account when calibrating the period-luminosity relationship
for Cepheids.
We have also compiled all available photometric data that revealed
that the pulsation period of AD Pup, the longest period Cepheid in
this sample, is continuously increasing with
ΔP=0.004567d/century, likely to be caused by stellar evolution.
The wave-like pattern superimposed on the parabolic O-C graph of
AD Pup may well be caused by the light-time effect in the binary
system. ST Vel also pulsates with a continuously increasing period.
The other four Cepheids are characterized with stable pulsation
periods in the last half century.
Description:
We performed a RV survey of Cepheids with the 2.3m ANU telescope
located at Siding Spring Observatory (SSO), Australia.
On 64 nights between 2004 October and 2006 March we monitored 40
Cepheids with pulsation periods between 2 and 30d.
(V898 Cen was observed in 2009 July too).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 69 6 Basic data of the programme stars and the
number of spectra
table3.dat 16 27 New RV values of GH Carinae from the SSO spectra
table4.dat 16 43 New CORALIE velocities of GH Carinae
table6.dat 16 26 New RV values of V419 Centauri from the SSO spectra
table9.dat 16 33 New RV values of V898 Centauri from the SSO spectra
table13.dat 16 33 New RV values of AD Puppis from the SSO spectra
table15.dat 16 22 New RV values of AY Sagittarii from the SSO spectra
table17.dat 16 27 New RV values of ST Velorum from the SSO spectra
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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- 8 A8 --- Star Star name
10- 14 F5.2 mag <Vmag> Mean V magnitude
16- 24 F9.6 d Per Period
26- 39 A14 --- Mode Mode of pulsation
42- 46 A5 --- Nobs Number of observations
48- 58 A11 --- FileName1 Name of the table with radial velocities
from SSO spectrum
60- 69 A10 --- FileName2 Name of the table with CORALIE radial velocities
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Byte-by-byte Description of file: table[3469].dat table1[357].dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d HJD Heliocentric Julian date (HJD-2400000)
12- 16 F5.1 km/s RV Radial velocity
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Jun-2017