Related papers: Cocoon shock breakout emission from binary neutron…
The cocoon is an inevitable product of a jet propagating through ambient matter, and takes a fair fraction of the jet energy. In short gamma-ray bursts, the ambient matter is the ejecta from the merger of neutron stars, expanding with a…
The short Gamma-Ray Burst, GRB170817A, that followed the binary neutron star merger gravitational waves signal, GW170817, is not a usual sGRB. It is weaker by three orders of magnitude than the weakest sGRB seen before and its spectra,…
We use relativistic hydrodynamic numerical calculations to study the interaction between a jet and a homologous outflow produced dynamically during binary neutron star mergers. We quantify how the thermal energy supplied by the jet to the…
Short Gamma-Ray Bursts (SGRBs) are believed to arise from compact binary mergers (either neutron star-neutron star or black hole-neutron star). If so their jets must penetrate outflows that are ejected during the merger. As a jet crosses…
Neutron star mergers are believed to occur in accretion disks around supermassive black holes. Here we show that a putative jet launched from the merger of a binary neutron star (BNS) or a neutron star--black hole (NSBH) merger occurring at…
We perform GRMHD and RMHD simulations of weakly and highly magnetized gamma-ray burst (GRB) jets propagating in binary neutron star (BNS) merger ejecta. Using the simulations, we first find that mixing between the jet and cocoon, which is…
In the gravitational wave event GW170817, there was a $\sim 10$ hours gap before electromagnetic (EM) observations, without detection of the cocoon. The cocoon is heated by a \textit{short} gamma-ray burst (\textit{s}GRB) jet propagating…
We present the first relativistic MHD numerical simulation of a magnetic jet that propagates through and emerges from the dynamical ejecta of a binary neutron star merger. Generated by the magnetized rotation of the merger remnant, the jet…
A supra-massive neutron star (NS) spinning extremely rapidly could survive from a merger of NS-NS binary. The spin-down of this remnant NS that is highly magnetized would power the isotropic merger ejecta to produce a bright mergernova…
Neutron star mergers (NSMs) eject energetic sub-relativistic dynamical ejecta into the circumbinary media. As analogous to supernovae and supernova remnants, the NSM dynamical ejecta are expected to produce non-thermal emission by electrons…
As a long GRB jet propagates within the surrounding stellar atmosphere it creates a cocoon composed of an outer Newtonian shocked stellar material and an inner (possibly relativistic) shocked jet material. The jet deposits $10^{51}-10^{52}$…
The first hours following a neutron star merger are considered to provide several UV/optical/NIR signals: $ \beta $-decay emission from free neutrons, radioactive decay of shocked heavy elements in the cocoon and cocoon's cooling emission.…
The discovery of GW170817, the merger of a binary neutron star (NS) triggered by a gravitational wave detection by LIGO and Virgo, has opened a new window of exploration in the physics of NSs and their cosmological role. Among the important…
Binary neutron stars mergers widely accepted as potential progenitors of short gamma-ray bursts. After the remnant of the merger has collapsed to a black hole, a jet is powered and may breakout from the the matter expelled during the…
Short $\gamma$-ray burst (sGRB) jets form in the aftermath of a neutron star merger, drill through disk winds and dynamical ejecta, and extend over four to five orders of magnitude in distance before breaking out of the ejecta. We present…
Follow-up observations of short gamma-ray bursts (sGRBs) have continuously unveiled late extended/plateau emissions, attributed to jet launch due to late engine activity, the nature of which remains enigmatic. Observations of GW170817…
We consider conditions for jet break-out through ejecta following mergers of neutron stars and provide simple relations for the break out conditions. We demonstrate that: (i) break-out requires that the isotropic-equivalent jet energy $E_j$…
The observations of a macronova/kilonova accompanied by gravitational waves from a binary neutron star merger (GW170817) confirmed that neutron star coalescences produce copious ejecta. The coincident gamma-ray detection implies the…
In addition to producing a strong gravitational signal, a short gamma-ray burst (GRB), and a compact remnant, neutron star mergers eject significant masses at significant kinetic energies. This mass ejection takes place via dynamical mass…
Fast ejecta expelled in binary neutron star (NS) mergers or energetic supernovae (SNe) should produce late-time synchrotron radio emission as the ejecta shocks into the surrounding ambient medium. Models for such radio flares typically…