J/AJ/142/87 Velocities and light curves of V350 Sgr (Evans+, 2011)
The orbit of the Cepheid V350 Sgr revisited.
Evans N.R., Berdnikov L., Gorynya N., Rastorguev A., Eaton J.
<Astron. J., 142, 87 (2011)>
=2011AJ....142...87E 2011AJ....142...87E
ADC_Keywords: Binaries, spectroscopic ; Radial velocities ; Photometry
Keywords: binaries: spectroscopic - stars: massive - stars: variables: Cepheids
Abstract:
"The Cepheid Mass Problem" is one of the fundamental tests of the
understanding of stellar evolution. One of the foundations of measured
masses for Cepheids for this question is binary orbits. V350 Sgr is a
classical Cepheid in a binary system. New radial velocity data for the
system have been obtained over the last several years, and are used to
update the orbit. The secondary in the system has previously had its
orbital velocity amplitude measured in the ultraviolet with the Hubble
Space Telescope. This amplitude has been combined with the new orbit
and the adopted mass of the secondary resulting in a Cepheid mass of
5.0±0.8M☉.
Description:
We have collected two extensive new sets of radial velocities at
Tennessee State University and Moscow University and added to them
some other recent data from the literature. These new data provide an
improved orbital solution, particularly the amplitude, which is the
crucial quantity for mass determination.
Eaton obtained high-dispersion spectra of V350 Sgr covering five years
(2005 February to 2009 October) with the Tennessee State University 2m
Automatic Spectroscopic Telescope (AST).
New data have also been obtained by the Moscow University radial
velocity program. The measurements are made with a CORAVEL-type
spectrometer from 1987 to 2010.
Objects:
-------------------------------------------------
RA (2000) DE Designation(s)
-------------------------------------------------
18 45 17.50 -20 38 50.6 V350 Sgr = HD 173297
-------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 43 337 Radial velocities and orbit
table4.dat 17 200 Standard curves of the Cepheid V350 Sgr in
filters B and V
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD Heliocentric Julian Date (HJD-2400000)
12- 17 F6.2 km/s RVtot Total radial velocity (1)
19- 23 F5.3 --- phiOrb Orbital phase φorb
25- 29 F5.3 --- phiPul Pulsation phase φpul
31- 35 F5.2 km/s RVorb Orbital radial velocity (1)
37- 41 F5.2 km/s O-C The (O-C) residuals
43 I1 --- Source Observation source code (2)
--------------------------------------------------------------------------------
Note (1): Radial velocities are listed including 2 decimal places for the
purpose of the solution, however they only accurate to a single
decimal place at best.
Note (2): Observation source code as follows:
1 = Gorynya et al. (1992PAZh...18..375G 1992PAZh...18..375G, 1996PAZh...22..198G 1996PAZh...22..198G,
1998, Cat. J/PAZh/24/939)
2 = Petterson et al. (2004MNRAS.350...95P 2004MNRAS.350...95P)
3 = Evans and Sugars (1997AJ....113..792E 1997AJ....113..792E)
5 = Gieren (1981ApJS...46..287G 1981ApJS...46..287G)
6 = Lloyd Evans (1980, SAAO Circ., 1, 257)
7 = Eaton (2007PASP..119..886E 2007PASP..119..886E), Table 1.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 F5.3 --- Phase Phase
7- 11 F5.3 mag Bmag B magnitude
13- 17 F5.3 mag Vmag V magnitude
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 12-Nov-2012