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The Nyquist frequency for irregularly spaced time-series: a calculation formula
(Oxford University Press, 2006)
Eyer & Bartholdi showed that the Nyquist frequency of irregularly sampled time-series can
be very high. In this paper, a calculation formula for the Nyquist frequency is presented. In
practice there is an upper limit of ...
KPD 0629–0016, a slowly pulsating hot subdwarf star
(Oxford University Press, 2007)
The results of nine CCD photometric observing runs on KPD 0629–0016 are presented. During
six of the runs measurements were obtained alternately through B and V filters. Four periodicities,
for which there is good agreement ...
Near-infrared time-series photometry of six fields in the young open cluster IC 2391
(Oxford University Press, 2006)
Fields containing targets of spectral types later than M5 were monitored in JHKs for about 7 h
each. None of the targets showed variability at levels exceeding 0.02 (or smaller, in some cases).
Seven new variable stars ...
JL 82: a slowly pulsating hot subdwarf star in a close binary system
(Oxford University Press, 2009)
JL 82 is a known binary, consisting of an sdB star and a companion which is not directly
observable in the optical. Photometric measurements reported in this paper show it to variable
with both the binary period (∼0.75 ...
What can be deduced from open cluster metallicity measurements?
(Oxford University Press, 2007)
The dependence of [Fe/H] on galactocentric distance, distance from the galactic mid-plane
and age is studied. Both ordinary least-squares and non-parametric regression in the form of a
‘generalized additive model’ are ...
Further observations of Hipparcos red stars and standards for UBV(RI)C photometry
(Oxford University Press, 2007)
We present homogeneous and standardized UBV(RI)C JHK photometry for over 100 M stars
selected from an earlier paper on the basis of apparent photometric constancy. L photometry
has been obtained for stars brighter than ...
Confidence intervals for the correlation between the gamma-ray burst peak energy and the associated supernova peak brightness
(Oxford University Press, 2009)
A strong correlation between the gamma-ray burster peak energy and the peak luminosity
of the associated supernova was discovered by Li for four GRBs. Despite the fact that the
formal significance level of the correlation ...
The detailed forms of the LMC Cepheid PL and PLC relations
(Oxford University Press, 2007)
Possible deviations from linearity of the Large Magellanic Cloud Cepheid period–luminosity
(PL) and period–luminosity–colour (PLC) relations are investigated. Two data sets are studied,
respectively from the Optical ...
The Nyquist frequency for time series with slight deviations from regular spacing
(Oxford University Press, 2009)
The paper is based on the notion that the Nyquist frequency νN is a symmetry point of the
periodogram of a time series: the power spectrum at frequencies above νN is a mirror image
of that below νN. Koen showed that the ...
The analysis of indexed astronomical time series – X. Significance testing of O − C data
(Oxford University Press, 2006)
It is assumed that O − C (‘observed minus calculated’) values of periodic variable stars are
determined by three processes, namely measurement errors, random cycle-to-cycle jitter in
the period, and possibly long-term ...