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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 ...
HE 0230−4323 revisited: a new rapidly pulsating sdB star
(Oxford University Press, 2010)
HE 0230−4323 is a hot sdB star in a binary system. An earlier work demonstrated that the
light curve of the system shows a strong (∼4 per cent) reflection effect and also appears to
exhibit photometric variations of 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 ...
Multicolour time series photometry of the T Tauri star CVSO 30
(Oxford University Press, 2015)
Five consecutive runs of at least five hours, and two shorter runs, of V(RI)C time series
photometry of CVSO 30 are presented. No evidence could be seen for planetary transits,
previously claimed in the literature for ...
A search for p-mode pulsations in white dwarf stars using the Berkeley Visible Imaging Tube detector
(Oxford University Press, 2014)
We present high-speed photometry (resolution 0.1 s) obtained during the commissioning of the
Berkely Visible Imaging Tube system on the Southern African Large Telescope (SALT). The
observations were an attempt to search ...
The analysis of indexed astronomical time series – XII. The statistics of oversampled Fourier spectra of noise plus a single sinusoid
(Oxford University Press, 2015)
With few exceptions, theoretical studies of periodogram properties focus on pure noise time
series. This paper considers the case in which the time series consists of noise together with a
single sinusoid, observed at ...
Is there evolution in the infrared Tully–Fisher relation? Comparing two linear regressions
(Oxford University Press, 2009)
In a recent paper, Puech and co-workers compared K-band Tully–Fisher relations derived
for nearby and distant galaxies, respectively. They concluded that the two relations differ,
and deduced that there is evolution in ...
Photometry of the magnetic white dwarf SDSS 121209.31+013627.7
(Oxford University Press, 2006)
The results of 27 h of time series photometry of SDSS 121209.31+013627.7 are presented.
The binary period established from spectroscopy is confirmed and refined to 0.061 412 d
(88.43 min). The photometric variations are ...
The analysis of irregularly observed stochastic astronomical time-series – I. Basics of linear stochastic differential equations
(Oxford University Press, 2005)
The theory of low-order linear stochastic differential equations is reviewed. Solutions to these
equations give the continuous time analogues of discrete time autoregressive time-series. Explicit
forms for the power ...
A re-assessment of the nearest neighbour alignment of the X-ray isophotes of galaxy clusters
(Oxford University Press, 2006)
Alignment is defined as the tendency of the distribution of pointing angles between the major
axes of clusters and their nearest neighbours to be more concentrated towards small values
for small nearest neighbour distances, ...