We present a new numerical code, PLUTO, for the solution of hypersonic flows in 1, 2, and 3 spatial dimensions different systems coordinates. The code provides multiphysics, multialgorithm modular environment particularly oriented toward treatment astrophysical presence discontinuities. Different hydrodynamic modules algorithms may be independently selected to properly describe Newtonian, relativistic, MHD, or relativistic MHD fluids. structure exploits general framework integrating system...

We present a description of the adaptive mesh refinement (AMR) implementation PLUTO code for solving equations classical and special relativistic magnetohydrodynamics (MHD RMHD). The current release exploits, in addition to static grid version code, distributed infrastructure CHOMBO library multidimensional parallel computations over block-structured, adaptively refined grids. employ conservative finite-volume approach where primary flow quantities are discretized at cell center...

We present an extension of the HLLC approximate Riemann solver by Toro, Spruce and Speares to relativistic equations fluid dynamics. The retains simplicity original two-wave formulation proposed Harten, Lax van Leer (HLL) but it restores missing contact wave in solution problem. resulting numerical scheme is computationally efficient, robust positively conservative. performance new evaluated through testing one two dimensions.

We describe a new hybrid framework to model non-thermal spectral signatures from highly energetic particles embedded in large-scale classical or relativistic MHD flow. Our method makes use of \textit{Lagrangian} moving through an Eulerian grid where the (relativistic) equations are solved concurrently. Lagrangian follow fluid streamlines and represent ensembles (real) with finite energy distribution. The distribution each particle is updated time by solving cosmic ray transport equation...

Context.Accretion disks and astrophysical jets are used to model many active objects, such as young stars, relativistic galactic nuclei. However, existing proposals for how these structures may transfer angular momentum energy from through viscous or magnetic torques do not yet provide a full understanding of the physical mechanisms involved. Thus, global stationary solutions have explained stability structures; numerical simulations that include both disk jet physics so far been limited...

We present an extension of the piecewise parabolic method to special relativistic fluid dynamics in multidimensions. The scheme is conservative, dimensionally unsplit, and suitable for a general equation state. Temporal evolution second-order accurate employs characteristic projection operators; spatial interpolation making third-order smooth regions flow away from discontinuities. algorithm written system orthogonal curvilinear coordinates can be used computations non-Cartesian geometries....

An approximate Riemann solver for the equations of relativistic magnetohydrodynamics (RMHD) is derived. The Harten–Lax–van Leer contact wave (HLLC) solver, originally developed by Toro, Spruce and Spears, generalizes algorithm described in a previous paper to case where magnetic fields are present. solution problem approximated two constant states bounded fast shocks separated tangential wave. scheme Jacobian-free, sense that it avoids expensive characteristic decomposition RMHD improves...

We present a five-wave Riemann solver for the equations of ideal relativistic magnetohydrodynamics. Our can be regarded as extension HLLD initially developed by Miyoshi and Kusano MHD. The solution to problem is approximated five wave pattern, comprised two outermost fast shocks, rotational discontinuities contact surface in middle. proposed scheme considerably more elaborate than classical case since normal velocity no longer constant across modes. Still, proper closure Rankine-Hugoniot...

Relativistic magnetized jets are key elements in Active Galactic Nuclei and other astrophysical environments. Their structure evolution involves a complex nonlinear physics that can be approached by numerical studies only. Still, owing to number of challenging computational aspects, only few investigations have been undertaken so far. In this paper, we present high-resolution three dimensional simulations relativistic carrying an initially toroidal magnetic field. The presence substantial...

This review explores the field of X-shaped radio galaxies (XRGs), a distinctive subset winged sources that are identified by two pairs jetted lobes which aligned significant angle, resulting in an inversion-symmetric structure. These lobes, encompassing active (primary) and passive (secondary) phases, exhibit diverse range properties across multiple frequency bands, posing challenges discerning their formation mechanism. The proposed mechanisms can broadly be categorized into those related...

view Abstract Citations (120) References (47) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Radio Jets and the Formation of Active Galaxies: Accretion Avalanches on Torus by Effect a Large-Scale Magnetic Field Matsumoto, R. ; Uchida, Y. Hirose, S. Shibata, K. Hayashi, M. Ferrari, A. Bodo, G. Norman, C. We present results 2.5-dimensional MHD simulations for magnetohydrodynamic model jet formation associated with active galaxies. also study enhanced accretion...

Context. Strong observational evidence indicates that all extragalactic jets associated with AGNs move at relativistic speed up to 100 pc-1 kpc scales from the nucleus. At greater distances, reflecting Fanaroff-Riley radio source classification, we observe an abrupt deceleration in FR-I while motions persist Mpc scale FR-II. Moreover, VLBI observations of some object such as B2 1144+35, Mrk501 and M87 show limb brightening jet emission on parsec scale. This effect is interpreted...

We perform a linear analysis of the stability magnetized relativistic non-rotating cylindrical flow in aproximation zero thermal pressure, considering only m = 1 mode. find that there are two modes instability: Kelvin-Helmholtz and current driven. The mode is found at low magnetizations its growth rate depends very weakly on pitch parameter. driven high value wavenumber maximum increase as we decrease In regime splitted branches, branch wavenumbers characterized by eigenfunction concentrated...

Extragalactic radio sources have been classified into two classes, Fanaroff-Riley I and II, which differ in morphology power. Strongly emitting belong to the edge-brightened FR II class, weakly edge-darkened class. The origin of this dichotomy is not yet fully understood. Numerical simulations are successful generating morphologies, but they fail reproduce diffuse structure Is. By means hydro-dynamical 3D supersonic jets, we investigate how displayed morphologies depend on jet parameters....

We have performed magneto-hydrodynamic simulations of relativistic jets from supermassive blackholes over a few tens kpc for range jet parameters. One the primary aims were to investigate effect different MHD instabilities on dynamics and their dependence choice find that two dominant affect jet, small scale Kelvin- Helmholtz (KH) modes large kink modes, whose evolution depend internal parameters like Lorentz factor, ratio density pressure external medium magnetisation hence consequently...

ABSTRACT We investigate with relativistic MHD (magnetohydrodynamic) simulations the dissipation physics of BL Lac jets, by studying synchrotron polarization signatures particles accelerated kink instability in a magnetically dominated plasma column. The non-linear stage generates current sheets, where can be efficiently via magnetic reconnection. identify sheets as regions s = Jδ/B is above some predefined threshold (where B field strength, J density, and δ grid scale), assume that particle...

Context. The recently discovered population of faint Fanaroff-Riley type 0 (FR0) radio galaxies has been interpreted as the extension to low power classical FRI sources. Their emission appears be concentrated in very compact parsec scale cores, any extended is weak or absent, and very-long-baseline interferometry (VLBI) observations show that jets are already mildly sub-relativistic at scales. Based on these observational properties, we propose here FR0s strongly decelerated disturbed by...

A new linear mechanism of wave abrupt emergence from vortices in smooth shear flows is found. The phenomenon closely related to non-normality dynamics disturbances and best interpreted the framework a nonmodal approach---by tracing spatial Fourier harmonics vortex time. Found phenomenon, demonstrated Letter for simplest example unbounded, compressible, plane Couette flow, should be important numerous engineering applications realized various terrestrial astrophysical flows.

A significant fraction of extended radio sources presents a peculiar X-shaped morphology: in addition to the classical double lobed structure, emission is also observed along second axis symmetry form diffuse wings or tails. We re-examine origin these extensions relating morphology properties their host galaxies. The orientation shows striking connection with structure galaxy as they are preferentially aligned its minor axis. Furthermore, only galaxies high projected ellipticity....

Aims. We study the changes in properties of turbulence driven by magnetorotational instability a shearing box, as computational domain size radial direction is varied relative to height.

Magnetohydrodynamic models of collimated outflows produced by accretion discs around compact objects can be used for interpreting the phenomenology active astrophysical as young stellar objects, microquasars, X-ray binaries, gamma-ray bursts, extended radio galaxies and galactic nuclei. In present work, we discuss how strength magnetic fields determines characteristics solutions in where outflow disc are treated consistently. We perform an extensive analysis field's non-relativistic...

We have simulated the evolution of non-thermal cosmic ray electrons (CREs) in 3D relativistic magneto hydrodynamic (MHD) jets evolved up to a height 9 kpc. The CREs been space and energy concurrently with jet fluid, duly accounting for radiative losses acceleration at shocks. show that stable MHD instabilities expected trends regular flow spine hotspot followed by settling backflow. However, unstable create complex shock structures jet-head (kink instability), spine-cocoon interface cocoon...

view Abstract Citations (67) References (38) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Nonlinear Evolution of Magnetohydrodynamic Kelvin-Helmholtz Instabilities Malagoli, Andrea ; Bodo, Gianluigi Rosner, Robert We investigate physical behavior in nonlinear regime (KH) instabilities a simple conducting shear flow presence magnetic fields, based upon use numerical simulations ideal magnetofluid equations motion two dimensions. The is characterized...

view Abstract Citations (88) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Thermal Instability of Galactic and Cluster Halos Malagoli, A. ; Rosner, R. Bodo, G. The paper presents a detailed study thermal instabilities in cooling flows associated with galaxies clusters galaxies. In case purely radiation-driven accretion onto central object such as cD galaxy M87, it is found that gas largely subject to overstability, rather than...