Related papers: Blunting the Spike: the CV Minimum Period
SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of cataclysmic variables (CVs) and CV candidates obtained during the final plug plate observations of SDSS.…
It is well known that Gamma-ray Burst spectra often display a break at energies $\simless 400$ keV, with some exceptions extending to several MeV.\ \ Modeling of a cosmological source population is thus non-trivial when comparing the…
A short period eclipsing binary star CV Boo is tested for the possible existence of additional bodies in the system with a help of the light equation method. We use data on the moments of minima from the literature as well as from our…
We derive metallicities for 41 cataclysmic variables (CVs) from near-infrared spectroscopy. We use synthetic spectra that cover the 0.8 $\mu$m $\leq \lambda \leq$ 2.5 $\mu$m bandpass to ascertain the value of [Fe/H] for CVs with K-type…
CX Cep (WR 151) is the WR+O binary (WN5+O5V) with the second shortest period known in our Galaxy. To examine the circumstellar matter distribution and to better constraint the orbital parameters and mass-loss rate of the WR star, we…
A binary in which a slightly evolved star starts mass transfer to a neutron star can evolve towards ultra-short orbital periods under the influence of magnetic braking. This is called magnetic capture. In a previous paper we showed that…
Despite the popularism of Bayesian neural networks in recent years, its use is somewhat limited in complex and big data situations due to the computational cost associated with full posterior evaluations. Variational Bayes (VB) provides a…
Variation in the angle $\alpha$ between a pulsar's rotational and magnetic axes would change the torque and spin-down rate. We show that sudden increases in $\alpha$, coincident with glitches, could be responsible for the persistent…
We have discovered a new high proper motion cataclysmic variable (CV) in the SUPERBLINK proper motion survey, which is sensitive to stars with proper motions greater than 40 mas/yr. This CV was selected for follow-up observations as part of…
We present 75 new stellar rotation periods in the young cluster IC348. Stars estimated to be less massive than 0.25 Mo show a unimodal distribution with a peak at P ~1-2 d) and a tail of slower rotators, while stars estimated to be more…
We have used a model of magnetic accretion to investigate the rotational equilibria of magnetic cataclysmic variables (mCVs). This has enabled us to derive a set of equilibrium spin periods as a function of orbital period and magnetic…
Magnetic braking has a prominent role in driving the evolution of close low mass binary systems and heavily influences the rotation rates of low mass F- and later type stars with convective envelopes. Several possible prescriptions that…
I discuss observational evidence -- independent of the direct spectral diagnostics of stellar winds themselves -- suggesting that mass-loss rates for O stars need to be revised downward by roughly a factor of three or more, in line with…
Rapidly rotating early-type stars with strong magnetic fields frequently show H$\alpha$ emission originating in Centrifugal Magnetospheres (CMs), circumstellar structures in which centrifugal support due to magnetically enforced corotation…
We model cataclysmic variables (CVs) with solar metallicity donors ($X=0.7,\:Z=0.02$) that evolve to form AM CVn stars through the Evolved CV formation channel using various angular momentum loss mechanisms by magnetic braking…
We investigate the slow passage through a pitchfork bifurcation in a spatially extended system, when the onset of instability is slowly varying in space. We focus here on the critical parameter scaling, when the instability locus propagates…
Radial velocity (RV) monitoring of solar-type visual binaries has been conducted at the CTIO/SMARTS 1.5-m telescope to study short-period systems. Data reduction is described, mean and individual RVs of 163 observed objects are given. New…
As the most extensively and continuously monitored neutron star, the Crab pulsar serves as representative of the earliest evolutionary stage. Its unique and complex glitch phenomenology provides an unparalleled testing ground for…
We report on spin variations in the intermediate polar and cataclysmic variable CC Scl, as seen by the Transiting Exoplanet Survey Satellite (TESS). By studying both the spin period and its harmonic, we find that the spin has varied since…
Spiral shocks in cataclysmic variables (CVs) are the result of tidal interactions of the mass donor star with the accretion disc. Their study is fundamental for our understanding of angular momentum transfer in discs. In our quest to learn…