Related papers: SDSS J0349-0059 is a GW Virginis star
Extensive photometric multisite campaigns of the Delta Scuti variable FG Vir are presented. For the years 2003 and 2004, 926 hours of photometry at the millimag precision level were obtained. The combinations with earlier campaigns lead to…
HS\,2324+3944 is a peculiar PG\,1159 star, with a high amount of H in its atmosphere (Dreizler et al. 1995). Its location in the $\log T_{\rm eff}$ -- $\log g$ plane is well inside the GW Vir instability strip. In this paper I report the…
We present the results from 135 hours of nearly continuous time series photometry on the ``hybrid'' (H-rich) PG1159 variable star HS2324+3944, obtained in August-September 1997. The power spectrum of the data shows several frequencies…
HD4539 (alias PG0044+097 or EPIC220641886) is a bright (V=10.2) long-period V1093 Her-type subdwarf B (sdB) pulsating star that was observed by the Kepler spacecraft in its secondary (K2) mission. We use the K2 light curve (78.7 days) to…
We report the detection of velocity variations in the pulsating sdB star, PG 1605+072. Oscillations are detected at the same frequencies found from photometry and have amplitudes of up to 14 km/s for H$\beta$. The strongest oscillation…
Grids of DOV star models are evolved by \texttt{WDEC} with fixed atmospheric constituent to the spectral values of $X_{C}/X_{He}/X_{O}$ = 50/33/17. The core compositions are from white dwarf models at highest $T_{eff}$ evolved by…
We report the detection of periodic variations on the T_eff ~32 000 K DA white dwarf star HE 1017-1352. We obtained time series photometry using the 4.1 m SOAR telescope on three separate nights for a total of 16.8 h. From the frequency…
Using multi-site spectroscopic data collected from three sites, the frequencies and pulsational modes of the {\gamma} Doradus star HD 12901 were identified. A total of six frequencies in the range 1-2 c/d were observed, their…
We performed time-series photometry of the PG1159-type star HE 1429-1209, which was recently discovered in the ESO SPY survey. We show that the star is a low-amplitude (about 0.05 mag) non-radial g-mode pulsator with a period of 919s. HE…
We have acquired 65 h of single-site time-resolved CCD photometry of the pulsating DB white dwarf star CBS 114 and 62 h of two-site high-speed CCD photometry of another DBV, PG 1456+103. The pulsation spectrum of PG 1456+103 is complicated…
PSR B1259-63 is a 48 ms pulsar in a highly eccentric 3.4 year orbit around the young massive star LS 2883. During the periastron passage the system displays transient non-thermal unpulsed emission from radio to very high energy gamma rays.…
We have obtained time-series spectra for the pulsating hot subdwarf (sdB) PG1605+072. Previous time-series photometry of this star has shown maximum amplitude variations of about 0.1 mag and at least 50 periods. The pulsator has the largest…
We present 154 MHz Murchison Widefield Array imaging observations and variability information for a sample of pulsars. Over the declination range $-80^{\circ} < {\delta} < 10^{\circ}$ we detect 17 known pulsars with mean flux density…
An asteroseismological study of PG 1159-035, the prototype of the GW Vir variable stars, has been performed on the basis of detailed and full PG1159 evolutionary models presented by Miller Bertolami & Althaus (2006). We carried out…
We present optical high-speed photometry of three millisecond pulsars with low-mass ($< 0.3 M_{\odot}$) white dwarf companions, bringing the total number of such systems with follow-up time-series photometry to five. We confirm the…
We report the discovery of two new accreting pulsating white dwarf stars amongst the cataclysmic variables of the Sloan Digital Sky Survey: SDSSJ074531.91+453829.5 and SDSSJ091945.10+085710.0. We observe high amplitude non-sinusoidal…
In the first spectroscopic campaign for a PG 1716 variable (or long-period pulsating subdwarf B star), we succeeded in detecting velocity variations due to g-mode pulsations at a level of 1.0-1.5 km/s.The observations were obtained during…
The supernova remnant G0.9+0.1 has long been inferred to contain a central energetic pulsar. In observations with the NRAO Green Bank Telescope at 2 GHz, we have detected radio pulsations from PSR J1747-2809. The pulsar has a rotation…
CONTEXT. The Lambda Bootis stars are a small spectroscopic subgroup of Population I A-type stars and show significant underabundances of metals. Many are Delta Scuti pulsators. AIMS. HD 210111 was selected for a detailed multisite pulsation…
An adiabatic, nonradial pulsation study of GW Vir stars is presented. The pulsation calculations are based on PG1159 evolutionary sequences with different stellar massess artificially derived from a full evolutionary sequence of 0.5895 Mo…