295 citations · 2k across the 40 of their papers we have counts for
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An Halpha-selected sample of cataclysmic variables -- II. Implications for CV evolution
Magaretha L. Pretorius, Christian Knigge
We use an independent new sample of cataclysmic variables (CVs), constructed by selecting objects for Halpha emission, to constrain the properties of the intrinsic CV population. T…
An Halpha-selected sample of cataclysmic variables -- I. Observations of newly discovered systems
Magaretha L. Pretorius, Christian Knigge
Strong selection effects are present in observational samples of cataclysmic variables (CVs), complicating comparisons to theoretical predictions. The selection criteria used to de…
Dwarf nova oscillations and quasi-periodic oscillations in cataclysmic variables -- VI. Spin rates, propellering, and coherence
Brian Warner, Magaretha L. Pretorius
We examine published observations of dwarf nova oscillations (DNOs) on the rise and decline of outbursts and show that their rates of change are in reasonable agreement with those…
The space density of cataclysmic variables: constraints from the ROSAT North Ecliptic Pole Survey
M. L. Pretorius, C. Knigge, D. O'Donoghue +3
We use the ROSAT North Ecliptic Pole (NEP) survey to construct a small, but purely X-ray flux-limited sample of cataclysmic variable stars (CVs). The sample includes only 4 systems…
IGR J16194-2810: a new symbiotic X-ray binary
N. Masetti, R. Landi, M. L. Pretorius +7
We here report on the multiwavelength study which led us to the identification of X-ray source IGR J16194-2810 as a new Symbiotic X-ray Binary (SyXB), that is, a rare type of Low M…
Cool Companions to White Dwarf Stars from the Two Micron All Sky Survey All Sky Data Release
D. W. Hoard, S. Wachter, Laura K. Sturch +5
We present the culmination of our near-infrared survey of the optically spectroscopically identified white dwarf stars from the McCook & Sion catalog, conducted using photometric d…
The influence of selection effects on the observed cataclysmic variable population: modelling and application to the Palomar-Green sample
Magaretha L. Pretorius, Christian Knigge, Ulrich Kolb
Large differences between the properties of the known sample of cataclysmic variable stars (CVs) and the predictions of the theory of binary star evolution have long been recognise…
Discovery of a new cataclysmic variable through optical variability and X-ray emission
Magaretha L. Pretorius, Christian Knigge
Aims: We present discovery observations of the new cataclysmic variable star (CV) 1RXS J092737.4-191529, as well as spectra and photometry of SY Vol. The selection technique that t…
Dwarf nova oscillations and quasi-periodic oscillations in cataclysmic variables -- V. Results from an extensive survey
Magaretha L. Pretorius, Brian Warner, Patrick A. Woudt
We present observations of dwarf nova oscillations (DNOs), longer period dwarf nova oscillations (lpDNOs), and quasi-periodic oscillations (QPOs) in 13 cataclysmic variable stars (…
Unveiling the nature of INTEGRAL objects through optical spectroscopy. III. Observations of seven southern sources
N. Masetti, M. L. Pretorius, E. Palazzi +9
Context. The detection, thanks to the INTEGRAL satellite, of a number of new hard X-ray sources calls for the identification of their nature by means of observations at longer wave…
Percolation Properties of Nearby Large-Scale Structures: Every Galaxy has a Neighbour
Anthony Fairall, D. Turner, M. L. Pretorius +4
The distribution of nearby (cz < 7500 km/s) galaxies has been explored by minimal spanning trees; allowance has been made for the drastic decrease of data with distance. The invest…
High Speed Photometry of SDSS J013701.06-091234.9
M. L. Pretorius, P. A. Woudt, B. Warner +3
We present high speed photometry of the Sloan Digital Sky Survey cataclysmic variable SDSS J013701.06-091234.9 in quiescence and during its 2003 December superoutburst. The orbital…
The Delta Scuti star FG Vir. V. The 2002 photometric multisite campaign
M. Breger, F. Rodler, M. L. Pretorius +15
A high-accuracy multisite campaign was carried out from 2002 January to May with a photometric coverage of 398 hours at five observatories. The concentration on a few selected site…
High speed photometry of faint Cataclysmic Variables: IV. V356 Aql, Aqr1, FIRST J1023+0038, Ha 0242-2802, GI Mon, AO Oct, V972 Oph, SDSS 0155+00, SDSS 0233+00, SDSS 1240-01, SDSS 1556-00, SDSS 2050-05, FH Ser
Patrick A. Woudt, Brian Warner, Magaretha L. Pretorius
We present results from high speed photometry of a further thirteen faint cataclysmic variables. V356 Aql (Nova Aql 1936) shows flare-like outbursts with recurrence time scales ~ 3…
2MASSJ0516288+260738: Discovery of the first eclipsing late K + Brown dwarf system?
S. L. Schuh, G. Handler, H. Drechsel +22
We report the discovery of a new eclipsing system less than one arcminute south of the pulsating DB white dwarf KUV 05134+2605. The object could be identified with the point source…
Dwarf Nova Oscillations and Quasi-Periodic Oscillations in Cataclysmic Variables: III. A New Kind of Dwarf Nova Oscillation, and Further Examples of the Similarities to X-Ray Binaries
Brian Warner, Patrick A. Woudt, Magaretha L. Pretorius
We present measurements of the periods of Dwarf Nova Oscillations (DNOs) and Quasi-Periodic Oscillations (QPOs) in Cataclysmic Variable stars (CVs), many culled from published lite…
Preparing the COROT space mission: incidence and characterisation of pulsation in the Lower Instability Strip
E. Poretti, R. Garrido, P. J. Amado +24
By pursuing the goal to find new variables in the COROT field-of-view we characterised a sample of stars located in the lower part of the instability strip. Our sample is composed…