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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 ...
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, ...
On the upper limit on stellar masses in the Large Magellanic Cloud cluster R136
(Oxford University Press, 2006)
A truncated power-law distribution is fitted to the 29 largest stellar masses known in R136.
Two different statistical techniques are used, with comparable results. An upper limit to the
mass distribution of the order ...
JHKs time-series observations of a few ultracool dwarfs
(Oxford University Press, 2005)
The M8.5 object SSSPM J0109−5101 has recently been shown to be both a periodic and a
flaring variable, based on optical observations in the extreme red. More than 16 h of monitoring
in the near-infrared (NIR) reported ...
Multicolour time series photometry of 2MASS 1207−3932
(Oxford University Press, 2008)
Time series photometry in VRI of the young brown dwarf Two-Micron All-Sky Survey
(2MASS) J1207334−393254 is presented. Variability in I is insignificant, but amplitudes
up to ∼0.2 mag in R, and ∼0.55 mag in V, are seen ...