Related papers: Jets are the most robust observable ingredient of …
The formation of collimated outflows or jets in planetary nebulae (PNe) is not well understood. There is no evidence for active accretion disks in PNe making it difficult to decide which of several proposed jet formation scenarios may be…
We use the binary module of the MESA code to study the evolution of an evolved binary system where we assume that a main sequence companion removes the outskirts of the envelope of an asymptotic giant branch (AGB) star by launching jets,…
I summarize recent analytical and numerical studies of the common envelope (CE) process and suggest to replace the commonly used alpha-prescription for the CE ejection by a prescription based on final migration and jets launched by the…
Using the stellar evolution code MESA, we mimic the negative jet feedback mechanism in common envelope evolution (CEE) of low-mass main sequence stars, M2=0.1-0.2Mo, spiraling inward inside the envelopes of asymptotic giant branch (AGB) or…
Common-envelope events (CEEs), during which two stars temporarily orbit within a shared envelope, are believed to be vital for the formation of a wide range of close binaries. For decades, the only evidence that CEEs actually occur has been…
I compared with each other and with observations three energy sources to power intermediate luminosity optical transients (ILOTs) and conclude that only jets can power bright ILOTs with rapidly rising lightcurves. I present an expression…
The morphologies of planetary nebula have long been believed to be due to wind shaping processes in which a fast wind from the central star impacts a previously ejected envelope. Asymmetries assumed to exist in the slow wind envelope lead…
There is clear observational evidence that the main Class 0/I stages of the star formation process are associated with powerful collimated outflows (jets), which sometimes propagate up to distances as large as $10^{4-5}$ au scales in…
Common envelope evolution (CEE) occurs in some binary systems involving asymptotic giant branch (AGB) or red giant branch (RGB) stars, and understanding this process is crucial for understanding the origins of various transient phenomena.…
We find that the convective motion in the envelopes of red supergiant (RSG) stars supplies a non-negligible stochastic angular momentum to the mass that a secondary star accretes in a common envelope evolution (CEE), such that jets that the…
Evolution of close binaries often proceeds through the common envelope stage. The physics of the envelope ejection (CEE) is not yet understood, and several mechanisms were suggested to be involved. These could give rise to different…
We simulate the evolution of eccentric binary systems in the frame of the grazing envelope evolution (GEE) channel for the formation of Type IIb supernovae (SNe IIb), and find that extra mass removal by jets increases the parameter space…
In relation to two meetings on stellar binary systems in July 2017, I summarize my view that in the majority of strongly interacting stellar binary systems jets play decisive roles. In the meeting The Physics of Evolved Stars II: The role…
We study the grazing envelope evolution (GEE), where a secondary star, which orbits the surface of a giant star, accretes mass from the giant envelope and launches jets. We conduct simulations of the GEE with different half-opening angles…
Common-envelope evolution (CEE) is one of the biggest open questions in binary stellar evolution, despite being the main channel for the formation of close binaries. One of the main reasons CEE is difficult to model is the lack of direct…
We report on a study of the time sequence for the appearance of high-velocity jets and equatorial tori in the transition of stars from the asymptotic giant branch to the planetary nebulae phase. Jets and tori are prominent features of this…
Jets launched from a compact object (CO) during a common envelope (CE) may play a key role in the evolution of the system, and may also be an efficient removal channel for its material. In this work we study, through a large set of…
The common envelope evolution (CEE) is vital in forming short orbital period compact binaries. It covers many objects, such as double compact merging binaries, type Ia supernovae progenitors, binary pulsars, and X-ray binaries. Knowledge…
The common-envelope (CE) phase is a crucial stage in binary star evolution because the orbital separation can shrink drastically while ejecting the envelope of a giant star. Three-dimensional (3D) hydrodynamic simulations of CE evolution…
We investigate the time sequence for the appearance of jets and molecular tori in the transition of stars from the Asymptotic Giant Branch to the planetary nebula phase. Jets and tori are prominent features of this evolution, but their…