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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 ...
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 ...
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 ...
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 ...