J/PAZh/35/199 V,pg light curves of NSV 9159 (Berdnikov+, 2009)
Search for evolutionary changes in Cepheid periods using the Harvard plate
collection: NSV 9159.
Berdnikov L.N., Pastukhova E.N., Turner D.G., Majaess D.J.
<Pis'ma Astron. Zh. 35, 199 (2009)>
=2009PAZh...35..199B 2009PAZh...35..199B
=2009AstL...35..175B 2009AstL...35..175B
ADC_Keywords: Stars, variable ; Photometry
Keywords: Cepheids - period variability - stellar evolution
Abstract:
We have obtained 530 photographic magnitude estimates for the
long-period classical Cepheid NSV 9159 (P=39d) in the plate
collections of the Harvard Observatory and the Sternberg Astronomical
Institute. Together with the currently available CCD observations from
the ASAS-3 catalog, our data have allowed us to construct an O-C
diagram spanning a time interval of 119 years. The O-C diagram has the
shape of a parabola, which has made it possible to determine for the
first time the quadratic light elements and to calculate the rate of
evolutionary decrease in the period, 314.4(±7.3)s/yr, in agreement
with the results of theoretical calculations for the second crossing
of the instability strip. The available data reduced by the
Eddington-Plakidis method do not reveal any noticeable random
fluctuations in the period.
Description:
The oldest plate with NSV 9159 was taken at the Harvard Observatory in
1889 and the latest CCD image was obtained in 2008. Consequently, our
data span a time span of 119 years.
Objects:
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RA (2000) DE Designation(s)
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17 33 57.1 -20 30 23 NSV 9159 = SV* P 4349
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 65 45 Times of maximum light for NSV 9159
table3.dat 19 200 Standard V and PG light curves for NSV 9159
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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- 9 F9.1 d JDmax Heliocentric Julian date of maximum
11- 13 F3.1 d e_JDmax rms uncertainty on JD
15- 16 A2 --- Filt [V PG] Filter
18- 21 I4 --- E Epoch number (1)
23- 27 F5.1 d O-C O-C residuals
29- 30 I2 --- N Number of observations
32- 65 A34 --- Ref Data source
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Note (1): maxJDhel = 2433738.77(±0.67)
+ 38.87484(±0.00137)E
- 0.19367x10-3(±0.44928x10-5)E2
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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- 5 F5.3 --- Phase [0/1] Phase
7- 12 F6.3 mag Vmag V magnitude
14- 19 F6.3 mag pgmag Photographic magnitude
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 02-Apr-2009