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Evidence for rapid evolution of periodic variations in an ultracool dwarf
(Oxford University Press, 2006)
The results of three short photometric monitoring runs on the L0 dwarf 2MASS
J06050196−2342270, during three consecutive nights, are presented. The observations show
the persistent presence of a 2.4-h period, with an IC ...
IC and RC band time-series observations of some bright ultracool dwarfs
(Oxford University Press, 2005)
The results of more than 100 h of CCD photometric monitoring of 10 L dwarfs and two T dwarfs
are presented. Reasonable evidence is shown for IC band variability in DENIS 0255−4700,
DENIS 1705−0516 and 2M 2104−1037. ...
HE0230–4323: an unusual pulsating hot subdwarf star
(Oxford University Press, 2007)
HE 0230−4323 is a known binary, consisting of a subdwarf star and a companion which is not
observable in the optical. Photometric measurements reported in this paper have shown it to be
both a reflection-effect and a ...
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 ...
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 ...
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 ...
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 ...