Search
Now showing items 1-7 of 7
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 ...
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 ...
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 ...
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 ...
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 ...