J/AJ/129/2007 Photometry of type II Cepheids. II (Schmidt+, 2005)
Photometry of type II Cepheids. II. The short-period stars.
Schmidt E.G., Johnston D., Langan S., Lee K.M.
<Astron. J., 129, 2007-2017 (2005)>
=2005AJ....129.2007S 2005AJ....129.2007S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Photometry
Keywords: Cepheids
Abstract:
We present 668 new photometric observations for 24 Cepheids with
periods less than 3 days. Most of the stars are probable type II
Cepheids, but we have included some type I Cepheids for comparison. A
discussion of the Fourier parameters of the light curves leads to the
conclusion that they can be used to distinguish among the several
types of light curves found among the type II stars but are of limited
usefulness for distinguishing between type I and type II Cepheids.
Description:
The observations were all made at Behlen Observatory with the 0.76m
telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 24 The program stars
table3.dat 72 24 The light-curve parameters
table4.dat 74 24 The Fourier parameters
table2.dat 41 668 Photometric data
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See also:
II/250 : Combined General Catalogue of Variable Stars (Samus+ 2004)
V/48 : A CATALOGUE OF FIELD TYPE II CEPHEIDS
J/AJ/128/1748 : VR photometry of type II cepheids (Schmidt+, 2004)
II/217 : Photoelectric observations of Cepheids in UBV(RI)c
(Berdnikov, 1997)
J/A+AS/143/211 : Galactic Cepheids BVRI photometry (Berdnikov+, 2000)
J/A+A/404/423 : BVI photometry of Galactic Cepheids (Tammann+, 2003)
J/AJ/130/832 : VR photometry of type II Cepheids. III (Schmidt+, 2005)
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 Star name
10- 13 F4.2 d Per Approximate period
15- 19 A5 --- Class GCVS classification (Cat. II/250)
21- 22 A2 --- f_Name [II] Type II Cepheid of Harris catalog (1985,
Cat. V/48)
24- 39 A16 --- LCType Light-curve type (1)
41 I1 --- Nc Number of comparison stars used for each field
43- 44 I2 --- sigVmag ? Standard error of the adopted V magnitude of
the comparison stars
46- 47 I2 --- sigRmag ? Standard error of the adopted R magnitude of
the comparison stars
49- 50 I2 --- Nnights Number of photometric nights
51 A1 --- f_Nnights Flag on Nnights (2)
53- 59 I7 d HJD1 Julian date of start of observation
60 A1 --- --- [-]
61- 67 I7 d HJD2 Julian date of end of observation
69- 71 I3 --- Ntot Total number of light-curve points available
73- 74 I2 --- Nnew Number of new points presented here
76- 88 A13 --- Ref Sources of the earlier photometry (3)
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Note (1): From Diethelm (1990A&A...239..186D 1990A&A...239..186D) for stars listed here, and
assigned by the authors for stars he did not include. The latter are
enclosed in parentheses to distinguish them.
Note (2): Flag on Nnights, defined as follows:
a = The zero point of our V magnitudes was adjusted to produce agreement
with earlier photometry.
b = For CE Her the zero points for both V and R were set by comparing the
present photometry with that of Loomis et al. (1988MNRAS.235.1059L 1988MNRAS.235.1059L).
c = We have classed V714 Cyg as AHB2 based on the bump on rising light, but
it is unique among our sample in also having a bump on the falling
branch of the light curve.
d = For UY Eri the zero point of the V magnitudes transformed from Pel's
(1976A&AS...24..413P 1976A&AS...24..413P) Walraven photometry was adjusted.
Note (3): References as follows:
1 = Berdnikov 1987PZ.....22..530B 1987PZ.....22..530B; 1992, A&A Trans., 2, 31;
1992, A&A Trans., 2, 43; 1992, A&A Trans., 2, 107;
1992, A&A Trans., 2, 157; 1992PAZh...18..325B 1992PAZh...18..325B, 1993PAZh...19..210B 1993PAZh...19..210B
2 = Kwee & Diethelm, 1984A&AS...55...77K 1984A&AS...55...77K
3 = Henden, 1980MNRAS.192..621H 1980MNRAS.192..621H; 1996, Cat. J/AJ/112/2757
4 = Harris, 1980 Ph.D. thesis, Univ. Washington
5 = Loomis et al., 1988MNRAS.235.1059L 1988MNRAS.235.1059L
6 = Szabados, 1977, Mitt. Sternw. Akad. Wiss., 70
7 = Moffett & Barnes, 1984ApJS...55..389M 1984ApJS...55..389M
8 = Barnes et al., 1997PASP..109..645B 1997PASP..109..645B
9 = Schmidt & Reiswig, 1993, Cat. J/AJ/106/2429
10 = Diethelm & Tammann, 1982A&AS...47..335D 1982A&AS...47..335D
11 = Sturch, 1966PASP...78..210S 1966PASP...78..210S
12 = Harris & Wallerstein, 1984AJ.....89..379H 1984AJ.....89..379H
13 = Schmidt & Seth, 1996, Cat. J/AJ/112/2769
14 = Schmidt et al., 1995AJ....109.1239S 1995AJ....109.1239S
15 = Pel, 1976A&AS...24..413P 1976A&AS...24..413P (Walraven photometry transformed to the
Johnson system using VJ=6.874-2.5[VW-0.065(VW-BW)] from the
same reference).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Star name
10- 18 F9.7 d Per Adopted period
20- 23 I4 10-7d e_Per Upper limit on the uncertainty of the period
25- 29 I5 10-7d DPer Difference between the period Per and the
period from the GCVS
31- 40 F10.2 d HJD Epoch of maximum, based on the most recent
photometry
42- 46 F5.2 mag <Vmag> Mean V magnitude
48- 52 F5.2 mag <Rmag> ? Mean R magnitude
54- 57 F4.2 mag Vamp V amplitude
59- 62 F4.2 mag Ramp ? R amplitude
64- 67 F4.2 --- Phi Phase of minimum light
69- 72 A4 --- Notes Notes (1)
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Note (1): Notes, defined as follows:
a = The new period and light-curve parameters were determined from all of
the available data.
b = The new period is not significantly different from the GCVS period,
therefore the latter was used. The light-curve parameters were
determined from all of the data.
c = Our photometry of VX Cap was limited to phases from about maximum light
through minimum. The light-curve point nearest maximum and that nearest
minimum were both too bright compared with the photometry of Kwee &
Diethelm (1984A&AS...55...77K 1984A&AS...55...77K), therefore we have corrected our V
magnitudes to produce agreement. Without this correction the period
derived would be 1.327552±0.000004 days. While this is closer to
the GCVS period, the fit of the photometry is poorer. Further data are
needed to resolve this ambiguity.
d = Because of the large scatter, the period for MQ Aql is poorly defined.
The cited value was derived by minimizing scatter during rising light.
e = For SW Tau the light-curve parameters, other than the period, were
determined from the present photometry only.
f = The period listed for V745 Oph is based on the present data. The Kwee &
Diethelm (1984A&AS...55...77K 1984A&AS...55...77K) photometry required a period that is
smaller by 0.0007 days. Only the present data were used for deriving
the light-curve parameters.
g = The period for BB Gem was determined from the present photometry and
that of Henden (1980MNRAS.192..621H 1980MNRAS.192..621H). Only the present photometry was
used to derive the other photometric parameters.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Star name
10- 13 F4.2 --- R21 Fourier parameter (amplitude ratio)
15- 18 F4.2 --- e_R21 Error in R21
20- 23 F4.2 --- R31 Fourier parameter (amplitude ratio)
25- 28 F4.2 --- e_R31 Error in R31
30- 33 F4.2 --- R41 ? Fourier parameter (amplitude ratio)
35- 38 F4.2 --- e_R41 ? Error in R41
40- 43 F4.2 --- phi21 Fourier phase
45- 48 F4.2 --- e_phi21 Error in phi21
50- 53 F4.2 --- phi31 Fourier phase
55- 58 F4.2 --- e_phi31 Error in phi31
60- 63 F4.2 --- phi41 ? Fourier phase
65- 68 F4.2 --- e_phi41 ? Error in phi41
70- 74 F5.3 --- sigma Standard deviation
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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- 8 A8 --- Name Star name
10- 20 F11.3 d HJD Heliocentric Julian Date of observation
22- 27 F6.3 mag Vmag The V band magnitude
29- 34 F6.3 mag Rmag The R band magnitude
36- 41 F6.3 mag V-R The (V-R) color index
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History:
From electronic version of the journal
References:
Schmidt et al., Paper I 2004AJ....128.1748S 2004AJ....128.1748S, Cat. J/AJ/128/1748
Schmidt et al., Paper III 2005AJ....130..832S 2005AJ....130..832S, Cat. J/AJ/130/832
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 07-Apr-2006