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Correcting CCD photometry of stars for seeing effects
(Oxford Univeristy Press, 2009)
Systematic variability in stellarmagnitudes, as derived from profile fitting to CCD images,may
in some instances be due to variable seeing. It is suggested that this happens in cases where the
stars are unresolved pairs, ...
Multivariate comparisons of the period–light-curve shape distributions of Cepheids in five galaxies
(Oxford University Press, 2007)
A number of published tests suitable for the comparison of multivariate distributions are
described. The results of a small power study, based on realistic Cepheid log period – Fourier
coefficient data, are presented. ...
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 ...
Two new variable sdB stars, HE 0218−3437 and LB 1516
(Oxford University Press, 2010)
We present photometry which shows that two known hot subdwarf stars, HE 0218−3437 and
LB 1516, are variable. LB 1516 exhibits several frequencies in the range 12–25 cycles d−1
(periods of about 1–2 h) with amplitudes ...
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 ...
Detection of an increasing orbital period in the subdwarf B eclipsing system NSVS 14256825
(Oxford University Press, 2012)
New timings of eclipses made in 2010 and 2011 are presented for the hot subdwarf B (sdB)
eclipsing binary NSVS 14256825. Composed of an sdB star and a much cooler companion,
with a period near 0.1104 days, this system ...
UBV(RI)C JHK observations of Hipparcos-selected nearby stars
(Oxford University Press, 2010)
We present homogeneous, standardized UBV(RI)C photometry for over 700 nearby stars
selected on the basis of Hipparcos parallaxes. Additionally, we list JHK photometry for about
half of these stars, as well as L photometry ...
Time series models of three sets of RXTE Observations of 4U 1543-47
(Oxford University Press, 2013)
The X-ray nova 4U 1543−47 was in a different physical state (low/hard, high/soft, and very high) during the
acquisition of each of the three time series analyzed in this paper. Standard time series models of the ...
Two large amplitude slowly pulsating hot subdwarf stars
(Oxford University Press, 2011)
The discovery observations of two new slowly pulsating subdwarf B stars (V1093 Her stars),
BPS CS22890−74 and PB 7032, are presented. Both stars are highly multiperiodic, and have –
for V1093 Her stars – large amplitudes. ...