J/MNRAS/331/45 New periodic variables (Koen+, 2002)
New periodic variables from the Hipparcos epoch photometry.
Koen C., Eyer L.
<Mon. Not. R. Astron. Soc. 331, 45 (2002)>
=2002MNRAS.331...45K 2002MNRAS.331...45K
ADC_Keywords: Stars, variable ; Magnitudes
Keywords: methods: data analysis - methods: statistical -
stars: variables: other
Abstract:
Two selection statistics are used to extract new candidate periodic
variables from the epoch photometry of the Hipparcos catalogue. The
primary selection criterion is a signal-to-noise ratio. The dependence
of this statistic on the number of observations is calibrated using
about 30000 randomly permuted Hipparcos data sets. A significance
level of 0.1 per cent is used to extract a first batch of candidate
variables. The second criterion requires that the optimal frequency be
unaffected if the data are de-trended by low-order polynomials. We
find 2675 new candidate periodic variables, of which the majority
(2082) are from the Hipparcos unsolved variables. Potential problems
with the interpretation of the data (e.g. aliasing) are discussed.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 54 2675 The selected candidate variable stars
table5.tex 78 2702 LaTeX version of table5
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP HIP number
8- 12 F5.2 mag Vmag V magnitude
14- 21 F8.5 d-1 Freq Frequency (1)
23- 28 F6.4 mag Amp Amplitude of the sinusoid (1)
30- 32 I3 --- Npoint Number of datapoints accepted
34- 39 F6.3 --- R* Signal-to-noise ratio statistic (2)
41- 52 A12 --- SpType MK Spectral classification
54 A1 --- VarClass [CMU] Hipparcos variability classification (3)
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Note (1): The frequency corresponding to the periodogram maximum was noted,
and a sinusoid with this frequency fitted to the data by linear least
squares.
Note (2): Candidate variables selected on the basis of sufficiently large
R* (R*>3.543) have good probabilities of being true variables.
See text for more explanations.
Note (3): Hipparcos variability:
C: constant
M: microvariable
U: unsolved
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Acknowledgements: Chris Koen
(End) James Marcout, Patricia Bauer [CDS] 06-May-2002