J/MNRAS/362/1167 Radial velocities of 14 southern Cepheids (Petterson+, 2005)
A spectroscopic study of bright southern Cepheids -
a high-resolution view of Cepheid atmospheres.
Petterson O.K.L., Cottrell P.L., Albrow M.D., Fokin A.
<Mon. Not. R. Astron. Soc., 362, 1167-1182 (2005)>
=2005MNRAS.362.1167P 2005MNRAS.362.1167P
ADC_Keywords: Stars, variable ; Radial velocities ; Spectroscopy
Keywords: stellar dynamics - stars: atmospheres - Cepheids
Abstract:
We present high-resolution spectroscopic observations and
species-by-species radial velocities of a number of southern Cepheids.
The stars (BP Cir, V350 Sgr, AX Cir, V636 Sco, W Sgr, S Mus,
β Dor, TT Aql, Y Oph, YZ Car, SW Vel, X Pup, T Mon and l Car)
were observed as part of a long-term programme at Mt John University
Observatory. Radial velocities were determined with the line bisector
technique, and have a precision of ∼300m/s. Velocity differences as
large as 30km/s were found for H and Ca II when referenced to the
metallic line velocity curves, but more subtle variations (of 12km/s)
were also detected in many other species. Pulsational phase
anticorrelations are found between lines of Si II and Ba II,
confirming the propagation time delay between line-forming layers
producing these two species. We find that the amplitude and phase
differences between the various species increase with period.
Description:
Observations were obtained with the 1-m McLellan reflector using the
high-resolution echelle spectrograph with the Series 200-CCD system
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 81 14 Cepheid periods
tablea.dat 98 418 Velocities
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See also:
J/ApJS/137/209 : Southern Cepheids BVIc photoelectric obs. (Berdnikov+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Cepheid name
12- 22 F11.3 JD Epoch Epoch
25- 33 F9.6 d Per Period
37- 81 A45 --- r_Per Source for period
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Byte-by-byte Description of file: tablea.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Cepheid name
10- 21 F12.4 d JD Julian date
23- 28 F6.4 --- Phase [0/1] Phase
30- 35 F6.2 km/s RV ?=- Radial velocity
37- 42 F6.2 km/s MVel Metallic velocity
44- 49 F6.2 km/s HaVel ?=- Hα velocity
51- 56 F6.2 km/s CaIIVel ?=- Ca II velocity
58- 63 F6.2 km/s CaIVel Ca I velocity
65- 70 F6.2 km/s BaIIVel Ba II velocity
72- 77 F6.2 km/s FeIVel Fe I velocity
79- 84 F6.2 km/s FeIIVel ?=- Fe II velocity
86- 91 F6.2 km/s SiIVel Si I velocity
93- 98 F6.2 km/s SiIIVel Si II velocity
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 11-May-2006