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My primary research focus is to study the formation and evolution of (radio) galaxies. Currently, I am involved in studying the origin and evolution of extended unusual radio galaxies (curved jetted sources), formation mechanism of which is still unclear. Specifically, I model the dynamical and radiative evolution of these sources in galactic, group and cluster scales using numerical simulations using a widely used astrophysical code gPLUTO. The Eulerian-Lagrangian framework of PLUTO code is a great tool to understand the micro-n-macro scaled physics of these radio galaxies. This includes several cooling processes, diffusive shock accelerations, effect of turbulence. My extended studies related to the 'I', 'S', 'X', 'C' shaped jetted sources have provided some crucial insight into these radio galaxies. Recently, I have been investigating the feed-back effects of these peculiar jetted sources on the cluster medium (e.g., X-ray cavities).
My primary research focus is to study the formation and evolution of (radio) galaxies. Currently, I am involved in studying the origin and evolution of extended unusual radio galaxies (curved jetted sources), formation mechanism of which is still unclear. Specifically, I model the dynamical and radiative evolution of these sources in galactic, group and cluster scales using numerical simulations using a widely used astrophysical code gPLUTO. The Eulerian-Lagrangian framework of PLUTO code is a great tool to understand the micro-n-macro scaled physics of these radio galaxies. This includes several cooling processes, diffusive shock accelerations, effect of turbulence. My extended studies related to the 'I', 'S', 'X', 'C' shaped jetted sources have provided some crucial insight into these radio galaxies. Recently, I have been investigating the feed-back effects of these peculiar jetted sources on the cluster medium (e.g., X-ray cavities).
On the other hand, colliding galactic systems are also one of my core interests related to the galaxy evolution. Currently, deep and wide observations of massive galaxies have shown the presence of faint asymmetric stellar structures in and around them, suggesting a merger origin. They are now being used explicitly to model the growth histories of these galaxies i.e., their evolution through time. Using data from dedicated deep optical-band surveys, I explore these faint merger structures to extract information regarding the past assembly histories, particularly in the context of the early-type galaxies.
On the other hand, colliding galactic systems are also one of my core interests related to the galaxy evolution. Currently, deep and wide observations of massive galaxies have shown the presence of faint asymmetric stellar structures in and around them, suggesting a merger origin. They are now being used explicitly to model the growth histories of these galaxies i.e., their evolution through time. Using data from dedicated deep optical-band surveys, I explore these faint merger structures to extract information regarding the past assembly histories, particularly in the context of the early-type galaxies.
I am also conducting research work on modelling turbulence in the context of astrophysical scenarios (e.g., inside the radio cocoon of jets). This is an exciting regime where I am entering now.
I am also conducting research work on modelling turbulence in the context of astrophysical scenarios (e.g., inside the radio cocoon of jets). This is an exciting regime where I am entering now.
Publication list
Publication list
Selected List:
Modelling X-shaped radio galaxies: Dynamical and emission signatures from the Back-flow model
Dynamical modelling and emission signatures of a candidate dual AGN with precessing radio jets
Remnants of recent mergers in nearby early-type galaxies and their classification
Deciphering the Morphological Origins of X-shaped Radio Galaxies: Numerical Modeling of Backflow versus Jet Reorientation
X-shaped radio galaxies: probing jet evolution, ambient medium dynamics, and their intricate interconnection
Probing the formation of megaparsec-scale giant radio galaxies-I. Dynamical insights from magnetohydrodynamic simulations
Probing the formation of megaparsec-scale giant radio galaxies-II. Continuum & polarization behavior from magnetohydrodynamic simulations
Simulation visualizations
Simulation visualizations
x-shape.mp4The evolution of relativistic jets in elliptical galactic environment is shown in this video, where we see the formation of different morphologies for different jet ejection directions. If the jet is propagating along the major axis of an elliptical environment, then the jet and the back-flowing jet materials together form an X-shaped morphology. We see for the jet ejection direction along the minor axis of the galaxy, a classical double-lobed jet structure is formed. It is not yet entirely clear if there is any preferred propagation direction for extragalactic jets with respect to their galactic axes (an open area of research!).
The evolution of relativistic jets in elliptical galactic environment is shown in this video, where we see the formation of different morphologies for different jet ejection directions. If the jet is propagating along the major axis of an elliptical environment, then the jet and the back-flowing jet materials together form an X-shaped morphology. We see for the jet ejection direction along the minor axis of the galaxy, a classical double-lobed jet structure is formed. It is not yet entirely clear if there is any preferred propagation direction for extragalactic jets with respect to their galactic axes (an open area of research!).
Radiative evolution of an X-shaped structure is shown in this video in frequencies 144 MHz and 43 GHz due to synchrotron radiation. The high frequency emission is only associated with the jet region originating from the freshly injected energetic jet particles. Whereas, the emission from 144 MHz is associated with the wing (secondary diffuse feature) region, which mostly have older cooling particle (compared to jet-spine). The emission maps are obtained in presence of diffusive shocks (particle energization process) and radiative and adiabatic cooling (loss processes) using the hybrid framework of PLUTO code.
Radiative evolution of an X-shaped structure is shown in this video in frequencies 144 MHz and 43 GHz due to synchrotron radiation. The high frequency emission is only associated with the jet region originating from the freshly injected energetic jet particles. Whereas, the emission from 144 MHz is associated with the wing (secondary diffuse feature) region, which mostly have older cooling particle (compared to jet-spine). The emission maps are obtained in presence of diffusive shocks (particle energization process) and radiative and adiabatic cooling (loss processes) using the hybrid framework of PLUTO code.
xshap_theta70_mov.mp4out.mp4Evolution of a precessing jet in a galactic environment is shown in this video, where with time the jet forms a distinct S-shaped source. The jet, of course, has a lower propagation speed, and therefore we are trying to mimic here an extragalactic S-shaped radio structure (2MASX J1203; Rubinur et al. 2017), which spans roughly 4 kiloparsecs in extent, clearly evolving inside its host galaxy.
Evolution of a precessing jet in a galactic environment is shown in this video, where with time the jet forms a distinct S-shaped source. The jet, of course, has a lower propagation speed, and therefore we are trying to mimic here an extragalactic S-shaped radio structure (2MASX J1203; Rubinur et al. 2017), which spans roughly 4 kiloparsecs in extent, clearly evolving inside its host galaxy.
A simulation of a giant radio jet (with a one-sided extent equivalent to the distance between our own galaxy, the Milky Way, and our neighbouring galaxy, Andromeda), representing the largest jet simulation to date (as of Giri et al. 2025), and considered the largest structure a galaxy can host or form. These were once thought to be rare cosmic structures, but modern-day radio telescopes, with their improved sensitivity and resolution, are now revealing more and more of them. This highlights the urgent need for dedicated numerical studies (which I am currently leading) to develop growth models for these giant radio galaxies.
A simulation of a giant radio jet (with a one-sided extent equivalent to the distance between our own galaxy, the Milky Way, and our neighbouring galaxy, Andromeda), representing the largest jet simulation to date (as of Giri et al. 2025), and considered the largest structure a galaxy can host or form. These were once thought to be rare cosmic structures, but modern-day radio telescopes, with their improved sensitivity and resolution, are now revealing more and more of them. This highlights the urgent need for dedicated numerical studies (which I am currently leading) to develop growth models for these giant radio galaxies.
Image, representing plasma-gas distribution forming the X-structure, injected from the bidirectional jet. The color of particles is set as per their injection time into the numerical domain. So a higher injection time indicates a freshly injected particle which are found mostly in the active jet lobe (primary structure). Older particles accumulate in the wings (secondary structure). The zoomed image shows the central plasma injection zone. The particles act as tracers to the fluid flow, aside from their critical role in modelling non-thermal emission more realistically.
Image, representing plasma-gas distribution forming the X-structure, injected from the bidirectional jet. The color of particles is set as per their injection time into the numerical domain. So a higher injection time indicates a freshly injected particle which are found mostly in the active jet lobe (primary structure). Older particles accumulate in the wings (secondary structure). The zoomed image shows the central plasma injection zone. The particles act as tracers to the fluid flow, aside from their critical role in modelling non-thermal emission more realistically.
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