Related papers: Tidally excited oscillations in MACHO 80.7443.1718…
The parameter space favourable for the resonant excitation of free oscillation modes by dynamic tides in close binary components is explored using qualitative considerations to estimate the order of magnitude of the tidal force and the…
We carry out high-speed photometry on 20 of the shortest-period, detached white dwarf binaries known and discover systems with eclipses, ellipsoidal variations (due to tidal deformations of the visible white dwarf), and Doppler beaming. All…
Improvements in the number of confirmed planets and the precision of observations imply a need to better understand subtle effects that may bias interpretations of exoplanet observations. One such effect is the distortion of a short period…
We have analysed radial velocity measurements for known transiting exoplanets to study the empirical signature of tidal orbital evolution for close-in planets. Compared to standard eccentricity determination, our approach is modified to…
We study the perturbations of a relatively close third star on a tidally distorted eccentric eclipsing binary. We consider both the observational consequences of the variations of the orbital elements and the interactions of the stellar…
Binary stars in which oscillations can be studied in either or both components can provide powerful constraints on our understanding of stellar physics. The bright binary 12 Bo\"otis (12 Boo) is a particularly promising system because the…
As a planet orbits, it causes periodic modulations in the light curve of its host star. Due to the combined effects of the planet raising tides on the host star, relativistic beaming of the starlight, and reflection of light off the…
We study the flux variation in helium white dwarfs (WDs) induced by dynamical tides for a variety of WD models with effective temperatures ranging from $T$=10 kK to $T$=26 kK. At linear order, we find the dynamical tide can significantly…
RX J1553.0+4457 (TMTS J15530469+4457458) is a detached post-common-envelope binary containing a cool white dwarf and an active late-type companion. We present a multi-wavelength study combining BOOTES multi-band photometry, six sectors of…
We update the ephemerides of 16 transiting exoplanets using our ground-based observations, new TESS data, and previously published observations including those of amateur astronomers. All these light curves were modeled by making use of a…
Tidal forces are important for understanding how close binary stars and compact exoplanetary systems form and evolve. However, tides are difficult to model and significant uncertainties exist about the strength of tides. Here, we…
Recent observation of the tidally-excited stellar oscillations in the main-sequence binary KOI-54 by the KEPLER satellite provides a unique opportunity for studying dynamical tides in eccentric binary systems. We develop a general theory of…
We present ground-based and Swift photometric and spectroscopic observations of the tidal disruption event (TDE) ASASSN-15oi, discovered at the center of 2MASX J20390918-3045201 ($d\simeq216$ Mpc) by the All-Sky Automated Survey for…
We study tidal dissipation in stars with masses in the range $0.1-1.6 M_\odot$ throughout their evolution, including turbulent effective viscosity acting on equilibrium tides and inertial waves in convection zones, and internal gravity…
A tidal interaction between a star and a close-in exoplanet leads to shrinkage of the planetary orbit and eventual tidal disruption of the planet. Measuring the shrinkage of the orbits will allow for the tidal quality parameter of the star…
We study the properties of waves in a facular region of moderate strength in the photosphere and chromosphere. Our aim is to analyse statistically the wave periods, power and phase relations as a function of the magnetic field strength and…
High-quality light curves from space missions have opened up a new window on the rotational and pulsational properties of magnetic chemically peculiar (mCP) stars and have fuelled asteroseismic studies. They allow the internal effects of…
The evolution of many close binary and multiple star systems is defined by phases of mass exchange and interaction. As these systems evolve into contact, tidal dissipation is not always sufficient to bring them into circular, synchronous…
Context. Determining the orbital periods of cataclysmic variable stars (CVs) is essential for confirming candidates and for the understanding of their evolutionary state. The Transiting Exoplanet Survey Satellite (TESS) provides month-long…
As part of our ongoing NTT SoFI survey for variability in young free-floating planets and low mass brown dwarfs, we detect significant variability in the young, free-floating planetary mass object PSO J318.5-22, likely due to rotational…