Related papers: The roAp star $\alpha$ Circini as seen by BRITE-Co…
The RApid Temporal Survey (RATS) is a survey to detect objects whose optical intensity varies on timescales of less than ~70 min. In our pilot dataset taken with the INT and the Wide Field Camera in Nov 2003 we discovered nearly 50 new…
The BRITE Constellation of nanosatellites obtained mmag photometry of 28 Cygni for 11 months in 2014-2016. Observations with the Solar Mass Ejection Imager in 2003-2010 and 118 H$\alpha$ line profiles were added. For decades, 28 Cyg has…
We present the first high-resolution X-ray spectrum of a prototypical Herbig star (AB Aurigae), measure and interpret various spectral features, and compare our results with model predictions. We use X-ray spectroscopy data from XMM-Newton.…
A 30-day contiguous photometric run with the MOST satellite on the WN5-6b star WR 110 (HD 165688) reveals a fundamental periodicity of P = 4.08 +/- 0.55 days along with a number of harmonics at periods P/n, with n ~ 2,3,4,5 and 6, and a few…
About 30.5 days of nearly uninterrupted broadband photometry of the solar-type star Kappa1 Ceti, obtained with the MOST (Microvariability & Oscillations of STars) satellite, shows evidence for two large starspots with different rotation…
We have searched for photometric variability in 95 Vir, a fast rotating, chromospherically active early F-type star, which was observed in the framework of Campaign 6 of the Kepler K2 mission. Available literature information on 95 Vir were…
We present the analysis of time-series of photoelectric data of a Bp star and four new Ap stars observed photoelectrically under the Nainital-Cape survey programme. The project was started about two decades ago, aiming to search for new…
HD149404 is an evolved non-eclipsing O-star binary that has previously undergone a Roche lobe overflow interaction. Understanding some key properties of the system requires a determination of the orbital inclination and of the dimensions of…
Photometric time series of the $\gamma$ Dor star 43 Cyg obtained with the BRITE-Constellation nano-satellites allow us to study its pulsational properties in detail and to constrain its interior structure. We aim to find a g-mode period…
We present an analysis of observations of the bright star Altair (alpha Aql) obtained using the star camera on the Wide-Field Infrared Explorer (WIRE) satellite. Although Altair lies within the delta Scuti instability strip, previous…
Circinus X-1 (Cir X-1) is a neutron star binary with an elliptical orbit of 16.6~days. The source is unique for its extreme youth, providing a key to understanding early binary evolution. However, its X-ray variability is too complex to…
Star formation in the solar neighborhood is mainly traced by young stars in open clusters, associations and in the field, which can be identified by their X-ray emission. The determination of stellar parameters for the counterparts of X-ray…
We present the preliminary results of the study of an interesting target in the first CoRoT exo-planet field (IRa1): CoRoT 102918586. Its light curve presents additional variability on the top of the eclipses, whose pattern suggests multi-…
An interesting asteroseismic target is the G9.5 IV solar-like star beta Aql. This is an ideal target for asteroseismic investigations, because precise astrometric measurements are available from Hipparcos that greatly help in constraining…
We present the results of a multisite photometric observing campaign on the rapidly oscillating Ap (roAp) star 2MASS 16400299-0737293 (J1640; $V=12.7$). We analyse photometric $B$ data to show the star pulsates at a frequency of $151.93$…
Observations of the red giant Arcturus (Alpha Boo) obtained with the star tracker on the Wide Field Infrared Explorer (WIRE) satellite during a baseline of 19 successive days in 2000 July-August are analysed. The power spectrum has a…
We present precise relative radial velocity (RV) measurements for the rapidly oscillating Ap (roAp) star 33 Librae measured from high resolution data spanning the wavelength interval 5000--6200 A. We find that pulsational radial velocity…
NainiTal-Cape Survey is a survey started with the aim of searching for new rapidly oscillating Ap stars in the northern hemisphere and has discovered one mono-periodic roAp star HD 12098. The frequency separation of HD 12098 suggests a…
In this paper we present a high-resolution spectroscopic analysis of the chemically peculiar star HD207561. During a survey programme to search for new roAp stars in the Northern hemisphere, Joshi et al. (2006) observed significant…
Solar-like oscillations have now been observed in several stars, thanks to ground-based spectroscopic observations and space-borne photometry. CoRoT, which has been in orbit since December 2006, has observed the star HD49933 twice. The…