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As part of the BANANA project (Binaries Are Not Always Neatly Aligned), we have found that the eclipsing binary CV Velorum has misaligned rotation axes. Based on our analysis of the Rossiter-McLaughlin effect, we find sky-projected spin-orbit angles of $beta_{rm p} = -52pm6^{circ}$ and $beta_{rm s}= 3pm7^{circ}$ for the primary and secondary stars (B2.5V $+$ B2.5V, $P=6.9$ d). We combine this information with several measurements of changing projected stellar rotation speeds ($v sin i_{star}$) over the last $30$ years, leading to a model in which the primary stars obliquity is $approx65^{circ}$, and its spin axis precesses around the total angular momentum vector with a period of about $140$ years. The geometry of the secondary star is less clear, although a significant obliquity is also implicated by the observed time variations in the $v sin i_{star}$. By integrating the secular tidal evolution equations backward in time, we find that the system could have evolved from a state of even stronger misalignment similar to DI Herculis, a younger but otherwise comparable binary.
With observations of the EP Cru system, we continue our series of measurements of spin-orbit angles in eclipsing binary star systems, the BANANA project (Binaries Are Not Always Neatly Aligned). We find a close alignment between the sky projections o
In the present study, high-precision time series photometry for the active emph{Kepler} stars is described in the language of multifractals. We explore the potential of using the rescaled range analysis ($R/S$) and multifractal detrended moving avera
Binaries are not always neatly aligned. Previous observations of the DI Her system showed that the spin axes of both stars are highly inclined with respect to one another and the orbital axis. Here we report on a measurement of the spin-axis orientat
We present numerical simulations, using two complementary setups, of rotating Boussinesq thermal convection in a three-dimensional Cartesian geometry with misaligned gravity and rotation vectors. This model represents a small region at a non-polar la
The triple stellar system delta Vel (composed of two A-type and one F-type main sequence stars) is particularly interesting as it contains one of the nearest and brightest eclipsing binaries. It therefore presents a unique opportunity to determine in