相关论文: The structure of jets launched from post-AGB binar…
The evolutionary state of the 198 day eclipsing binary BM Cas is examined using spectra that cover five orbital cycles. Radial velocities measured from SiII 6347 and SiII 6371 track the motion of the primary, and a mass function is found…
Binaries with circumbinary disks are commonly found among optically bright post-AGB stars. Although clearly linked to binary interaction processes, the formation, evolution and fate of these disks are still badly understood. Due to their…
Jets powered by AGN in the early Universe ($z \gtrsim 6$) have the potential to not only define the trajectories of the first-forming massive galaxies but to enable the accelerated growth of their associated SMBHs. Under typical…
The precession of astrophysical jets produced by active-galactic nuclei is likely related to the dynamics of the accretion disks surrounding the central supermassive black holes (BHs) from which jets are launched. The two main mechanisms…
Research in recent decades has seen many important advances in understanding the role of jets and outflows in the star formation process. Although, many open issues still remain, multi-wavelength high resolution observations have provided…
Intermediate mass stars (1-8 solar masses) evolve along the Asymptotic Giant Branch after completion of hydrogen and helium core burning. At the tip they lose for several ten to hundred thousand years copious amounts of mass and exhibit…
Exploring the formation and evolution of second-generation circumbinary discs around evolved binary stars, such as post-Asymptotic Giant Branch (post-AGB) and post-Red Giant Branch (post-RGB) binaries, provides valuable insights into the…
We report on optical, near-infrared and centimeter radio observations of GRB000418 which allow us to follow the evolution of the afterglow from 2 to 200 days after the gamma-ray burst. In modeling these broad-band data, we find that an…
Jets have been detected in only a few symbiotic binaries to date, and CH Cyg is one of them. In 2001, a non-relativistic jet was detected in CH Cyg for the first time in X-rays. We carried out coordinated Chandra, HST, and VLA observations…
Though widely observed to be emanating out from a variety of galactic and extra-galactic sources, the underlying physical mechanism behind the formation of the cosmic jets and outflows are wrapped around by the veil of mystery till date.…
We investigate the formation of binary stellar systems. We consider a model where a `seed' protobinary system forms, via fragmentation, within a collapsing molecular cloud core and evolves to its final mass by accreting material from an…
Jets and outflows are key components of low-mass star formation, regulating accretion and shaping the surrounding molecular clouds. These flows, traced by molecular species at (sub)millimeter wavelengths (e.g., CO, SiO, SO, H$_2$CO, and…
There is a group of post-AGB stars that are part of a binary system and that show a significant NIR excess. These systems are known to host disks with Keplerian or quasi-Keplerian dynamics and to drive outflows of gas escaping from the…
In recent work, we have identified two sub-populations of radio-loud AGN which appear to be distinguished by jet structure, where low-efficiency accreting systems produce `weak' jets which decelerate more rapidly than the `strong' jets of…
Symbiotic systems often include an asymptotic giant branch (AGB) star and a hot compact companion, such as a white dwarf, that are in close interaction. Due to the intense ultraviolet emission from the hot companion, the molecular content…
A structured gamma-ray burst jet could explain the dimness of the prompt emission observed from GRB$\,170817$A but the exact form of this structure is still ambiguous. However, with the promise of future joint gravitational wave and…
We present the first numerical simulations that track the evolution of a black hole-neutron star (BH-NS) merger from pre-merger to $r\gtrsim10^{11}\,{\rm cm}$. The disk that forms after a merger of mass ratio $q=2$ ejects massive disk winds…
Gamma-ray bursts (GRBs) associated with gravitational wave events are, and will likely continue to be, viewed at a larger inclination than GRBs without gravitational wave detections. As demonstrated by the afterglow of GW170817, this…
Kinematic signatures of the jet, winds, multicavities, and episodic shells arising in the unified model of bipolar outflows developed in Shang et al.\ (2020), in which an outflow forms by radially directed, wide-angle toroidally magnetized…
After being launched, GRB jets propagate through dense media prior to their breakout. The jet-medium interaction results in the formation of a complex structured outflow, often referred to as a "structured jet". The underlying physics of…