A5071313454- High-Energy Particle Collisions Research
- Gas Dynamics and Kinetic Theory
- Fluid Dynamics and Turbulent Flows
- Cosmology and Gravitation Theories
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Optical properties and cooling technologies in crystalline materials
- Pulsars and Gravitational Waves Research
- Quantum, superfluid, helium dynamics
- Black Holes and Theoretical Physics
- Computational Fluid Dynamics and Aerodynamics
- Energetic Materials and Combustion
- Dust and Plasma Wave Phenomena
- Guidance and Control Systems
- Electromagnetic Launch and Propulsion Technology
- Granular flow and fluidized beds
- Material Dynamics and Properties
The Ohio State University
2023-2024
Tata Institute of Fundamental Research
2019-2023
Using and comparing kinetic theory second-order Chapman-Enskog hydrodynamics, we study the nonconformal dynamics of a system undergoing Bjorken expansion. We use concept ``free-streaming fixed lines'' for scaled shear bulk stresses in show that these lines behave as early-time attractors repellors evolution. In conformal limit, free-streaming reduce to well-known points dynamics. A new point free streaming regime is identified which lies at intersection lines. Contrary scenario, both...
We consider causal higher order theories of relativistic viscous hydrodynamics in the limit one-dimensional boost-invariant expansion and study associated dynamical attractor. obtain evolution equations for inverse Reynolds number as a function Knudsen number. The solutions these exhibit attractor behavior which we analyze terms Lyapunov exponents using several different techniques. compare attractors second-order M\"uller-Israel-Stewart (MIS), transient DNMR, third-order with exact solution...
We study the dissipative evolution of (0+1)-dimensionally expanding media with Bjorken symmetry using Boltzmann equation for massive particles in relaxation-time approximation. Breaking conformal by a mass induces non-zero bulk viscous pressure medium. It is shown that even small (in units local temperature) drastically modifies well-known attractor shear Reynolds number previously observed massless systems. For generic nonzero particle mass, neither nor relax quickly to non-equilibrium...
Development of a new framework for derivation order-by-order hydrodynamics from Boltzmann equation is necessary as the widely used Anderson-Witting formalism leads to violation fundamental conservation laws when relaxation-time depends on particle energy, or in hydrodynamic frame other than Landau frame. We generalize an existing consistent relativistic dissipative with energy-dependent by extending approximation. argue that present compatible and derive first-order equations landau Further,...
We study the one-dimensional boost-invariant Boltzmann equation in relaxation-time approximation using special moments of distribution function for a system with finite particle mass. The infinite hierarchy can be truncated by keeping only three lowest that correspond to independent components energy-momentum tensor. show such three-moment truncation reproduces accurately exact solution kinetic after simple renormalization takes into account effects neglected higher moments. derive...
In this article, there are 18 sections discussing various current topics in the field of relativistic heavy-ion collisions and related phenomena, which will serve as a snapshot state art. Section 1 reviews experimental results some recent light-flavored particle production data from ALICE collaboration. Other mostly theoretical nature. Very strong but transient magnetic created could have important observational consequences. This has generated lot activity last decade. Sections 2, 7, 9, 10...
The discovery of hot and dense quantum chromodynamics (QCD) matter, known as Quark–Gluon Plasma (QGP), is an essential milestone in understanding the finite temperature QCD medium. Experimentalists around world collect unprecedented amount data heavy ion collisions, at Relativistic Heavy Ion Collider (RHIC), Brookhaven National Laboratory (BNL) New York, USA, Large Hadron (LHC), CERN Geneva, Switzerland. experimentalists analyze these to unravel mystery this new phase matter that filled a...
We use the extended relaxation time approximation for collision kernel, which incorporates a particle-energy dependent time, to derive second-order viscous hydrodynamics from Boltzmann equation system of massless particles. The resulting transport coefficients are found be sensitive energy dependence and have significant influence on fluid's evolution. Using derived hydrodynamic equations, we study evolution fluid undergoing ($0+1$)-dimensional expansion with Bjorken symmetry investigate...
We consider the evolution of a system chargeless and massless particles in an anisotropic space-time given by Bianchi type I metric. Specializing to axis-symmetric case, we derive framework hydrodynamics from Boltzmann equation relaxation-time approximation. case Kasner metric study approach emergent attractor near far-off-equilibrium regimes. Further, relaxing conditions on coefficients, effect expansion geometries discuss its implications context relativistic heavy-ion collisions.
We obtain general analytical solutions of third-order viscous hydrodynamic equations for Bjorken and Gubser flows in systems with vanishing bulk viscosity chemical potential, having a constant shear relaxation time. also analytically characterize determine the attractors such by studying universal behavior these at both early late times. Finally we study properties transport coefficients obtained from relativistic kinetic theory relaxation-time approximation.
We present an alternative approach to deriving second-order nonconformal hydrodynamics from the relativistic Boltzmann equation. demonstrate how constitutive relations for shear and bulk stresses can be transformed into dynamical evolution equations, resulting in Israel-Stewart-like (ISL) hydrodynamics. To understand far-from-equilibrium applicability of such ISL theories, we investigate one-dimensional boost-invariant equation using special moments distribution function a system with finite...
Study of thermal particle production is crucial to understand the space-time evolution fireball produced in high energy heavy-ion collisions. We consider within framework relativistic viscous hydrodynamics and employ recently obtained analytical solutions higher-order with longitudinal Bjorken expansion calculate spectra dileptons photons. Using these solutions, we constrain allowed initial states by demanding positivity reality density throughout evolution. Further, compute study yield...
We use the extended relaxation time approximation for collision kernel, which incorporates a particle-energy dependent time, to derive second-order viscous hydrodynamics from Boltzmann equation system of massless particles. The resulting transport coefficients are found be sensitive energy dependence and have significant influence on fluid's evolution. Using derived hydrodynamic equations, we study evolution fluid undergoing (0+1)-dimensional expansion with Bjorken symmetry investigate fixed...
We present an alternative approach to deriving second-order non-conformal hydrodynamics from the relativistic Boltzmann equation. demonstrate how constitutive relations for shear and bulk stresses can be transformed into dynamical evolution equations, resulting in Israel-Stewart-like (ISL) hydrodynamics. To understand far-from-equilibrium applicability of such ISL theories, we investigate one-dimensional boost-invariant equation using special moments distribution function a system with...
A lumped parameter model has been formulated. Model programmed in MATLAB. Different propulsion system parameters like propellant, cartridge case, igniter, projectile and gun are input to the program velocity chamber pressure distribution major outputs. The is validated with 105mm howitzer firing data from literature. model, only after incorporating variable burn rate coefficients pressure, tried 120mm tank of HEMRL reasonable agreement