Related papers: X-Ray Emission from Central Binary Systems of Plan…

Stellar evolutionary models predict that most of the early type subdwarf stars in close binary systems have white dwarf companions. More massive companions, such as neutron stars or black holes, are also expected in some cases. The presence…

We present an investigation into the rotation and stellar activity of four fully convective M dwarf `twin' wide binaries. Components in each pair have (1) astrometry confirming they are common-proper-motion binaries, (2) Gaia $BP$, $RP$,…

Although the majority of known binary Asymptotic Giant Branch (AGB) stars are symbiotic systems (i.e. with a WD as a secondary star), main-sequence companions of AGB stars can be more numerous, even though they are more difficult to find…

Based on time-dependent radiation-hydrodynamics simulations of the evolution of Planetary Nebulae (PNe), we have carried out a systematic parameter study to address the non-trivial question of how the diffuse X-ray emission of PNe with…

Some planetary nebulae (PNe) host X-ray-emitting hot bubbles shaped by stellar wind interactions and/or harbor X-ray-emitting central stars due to accretion, shocks within their fast stellar winds, or even chromospheric emission from binary…

Regardless of their different types of progenitors and central engines, gamma-ray bursts (GRBs) were always assumed to be standalone systems after they formed. Little attention has been paid to the possibility that a stellar companion can…

Magnetars are a unique class of neutron stars characterized by their incredibly strong magnetic fields. Unlike normal pulsars whose X-ray emission was driven by rotational energy loss, magnetars exhibit distinct X-ray emissions thought to…

For typical models of binary statistics, 50-70% of core-collapse supernova (ccSN) progenitors are members of a stellar binary at the time of the explosion. Independent of any consequences of mass transfer, this has observational…

In the era of Chandra and XMM-Newton, the detection (or nondetection) of diffuse and/or point-like X-ray sources within planetary nebulae (PNe) yields important, unique insight into PN shaping processes. Diffuse X-ray sources, whether due…

A growing number of early Be stars discovered in X-ray surveys exhibit X-ray luminosities intermediate between those of normal stars and those of most Be/X-ray binaries in quiescence. Their X-ray spectra are also much harder than those of…

In an attempt to determine how many planetary nebulae derive from binary interactions, we have started a project to measure their unbiased binary fraction. This number, when compared to the binary fraction of the presumed parent population…

Tight binary or multiple star systems can interact through mass transfer and follow vastly different evolutionary pathways than single stars. The star TYC 2597-735-1 is a candidate for a recent stellar merger remnant resulting from a…

LSI +61 303 is one of the few X-ray binaries with Be star companion from which both radio and high-energy gamma-ray emission have been observed. We present XMM-Newton and INTEGRAL observations which reveal variability of the X-ray spectral…

We present the results of Chandra X-ray Observatory (CXO) observations of the planetary nebulae (PNs) NGC 40 and Hen 2-99. Both PNs feature late-type Wolf-Rayet central stars that are presently driving fast ~1000 km/s, massive winds into…

The high mass loss rates of stars in their asymptotic giant branch (AGB) stage of evolution is one of the most important pathways for mass return from stars to the ISM. In the planetary nebulae (PNe) phase, the ejected material is…

It has been proposed multiple times to use the neutron star (NS) in high-mass X-ray binaries (HMXBs) as an orbiting X-ray probe embedded in the wind-fed of its supergiant (SG) companion in order to constrain the stellar line-driven wind…

We calculate the X-ray emission from the shocked fast wind blown by the central stars of planetary nebulae (PNs) and compare with observations. Using spherically symmetric self similar solutions, we calculate the flow structure and X-ray…

A scenario of the formation of isolated X-ray pulsars is discussed with an application to one of the best studied objects of this class 1E 161348-5055. This moderately luminous, 10^33 - 10^35 erg/s, pulsar with a relatively soft spectrum,…

We present a detailed study of the barium star at the heart of the planetary nebula Abell 70. Time-series photometry obtained over a period of more than ten years demonstrates that the barium-contaminated companion is a rapid rotator with…

It is well established that magnetars are neutron stars with extreme magnetic fields and young ages, but the evolutionary pathways to their creation are still uncertain. Since most massive stars are in binaries, if magnetars are a frequent…