Related papers: Magnetic Activity in Stellar Merger Products
Binary neutron star mergers are expected to produce fast dynamical ejecta, with mildly relativistic velocities extending to $\beta=v/c>0.6$. In a preceding paper, we derived an analytic description of the time-dependent radio to X-ray…
The merger of a neutron star (NS) binary may result in the formation of a long-lived, or indefinitely stable, millisecond magnetar remnant surrounded by a low-mass ejecta shell. A portion of the magnetar's prodigious rotational energy is…
Binary neutron star mergers are expected to produce fast dynamical ejecta, with mildly relativistic velocities extending to $\beta=v/c>0.6$. We consider the radio to X-ray synchrotron emission produced by collisionless shocks driven by such…
Accretion of interstellar material by a magnetized, slowly rotating isolated neutron star is discussed. We show that the average persistent X-ray luminosity of these objects is unlikely to exceed 4x10^26 erg/s. They can also appear as X-ray…
We present the first very long-term simulations (extending up to ~140 ms after merger) of binary neutron star mergers with piecewise polytropic equations of state and in full general relativity. Our simulations reveal that at a time of…
It is often assumed that gravitational wave (GW) events resulting from the merger of stellar-mass black holes are unlikely to produce electromagnetic (EM) counterparts. We point out that the progenitor binary has probably shed a mass…
V838 Mon erupted at the beginning of 2002 becoming an extremely luminous star. Among various scenarios proposed to explain the nature of the outburst the most promising is a stellar merger event. In this paper we investigate the…
Compact object mergers are multi-messenger sources and progenitors of some gamma-ray bursts (GRBs), primarily understood by gamma-ray observations, while poorly constrained in the prompt low-energy phase. A long-lasting X-ray emission was…
We investigate the simultaneous triggering of active galactic nuclei (AGN) in merging galaxies, using a large suite of high-resolution hydrodynamical simulations. We compute dual-AGN observability time-scales using bolometric, X-ray, and…
Stellar magnetic activity provides substantial information on the magnetic dynamo and the coronal heating process. We present a catalog of X-ray activity for about 6000 stars, based on the $Chandra$ and $Gaia$ DR2 data. We also classified…
Approximately 1/4-1/2 of short duration Gamma-Ray Bursts are followed by variable X-ray emission lasting ~ 100 s with a fluence comparable or exceeding that of the initial burst itself. The long duration and significant energy of this…
We consider scenario of merger of two stellar mass black holes surrounded by an accretion disk. Due to emission of gravitational waves, the mass of the central object decreases and accretion disk experiences perturbation. Calculations show…
In this letter we begin the study of visible dark sector signals coming from binary neutron star mergers. We focus on dark photons emitted in the 10 ms - 1 s after the merger, and show how they can lead to bright transient gamma-ray…
Merger of a white dwarf binary creates a differentially rotating object which is expected to generate strong magnetic fields. Kinetic energy stored in differential rotation is partially dissipated in the magnetically dominated corona, which…
Some classes of stars, including supernovae and novae, undergo explosive outbursts that eject stellar material into space. In 2002, the previously unknown variable star V838 Monocerotis brightened suddenly by a factor of about 10^4. Unlike…
Existing stellar X-ray surveys suggest major problems in our understanding of the evolution of stellar magnetic activity in solar and late-type stars, reaching conflicting conclusions over the rate of decay of X-ray activity and the…
Major mergers between galaxies are predicted to fuel their central supermassive black holes (SMBHs), particularly after coalescence. However, determining the prevalence of active galactic nuclei (AGNs) in mergers remains a challenge,…
The merger of a binary neutron star system is suggested as the central engine of short gamma-ray bursts (sGRBs). For the merger process, simulations predict that magnetic field is amplified beyond magnetar field strength by Kelvin-Helmholtz…
Stars of stellar type later than about M3.5 are believed to be fully convective and therefore unable to support magnetic dynamos like the one that produces the 11-year solar cycle. Because of their intrinsic faintness, very few late M stars…
Young stars typically have strong magnetic fields, so that the magnetospheres of newly formed close binaries can interact, dissipate energy, and produce synchrotron radiation. The V773 Tau A binary system, a pair of T Tauri stars with a 51…