Numerical Hydrodynamics in Special Relativity

Martí, J.; Müller, Ewald

doi:10.12942/lrr-2003-7

Cited by 243 publications

(255 citation statements)

References 257 publications

Supporting

Mentioning

249

Contrasting

Unclassified

Order By: Relevance

“…We also note the case of the quasar 3C 395 (Simon et al 1988;Lara et al 1994Lara et al , 1999, whose jet exhibits a possible stationary component due to possible bending of the jet. Martí & Müller (2003) model AGN jets and find that pressure mismatches exist between the jet and the surrounding medium. These lead to the production of reconfinement shocks and energy density enhancements downstream of these shocks, which in turn give rise to stationary radio knots.…”

Section: Jet Components At Constant Core Separationmentioning

confidence: 99%

The kinematics in the pc-scale jets of AGN

Britzen¹,

Kudryavtseva

Witzel³

et al. 2010

A&A

View full text Add to dashboard Cite

Context. BL Lac objects show core-jet structures with features moving outwards along the jet. We present a kinematic analysis of jet component motion in the pc-scale jet of the BL Lac object S5 1803+784, which does not reveal long-term outward motion for most of the components. Aims. S5 1803+784 shows complex kinematic phenomena; understanding these provides new insights into the emission processes in BL Lac objects and possibly into the differences between quasars and BL Lac objects. Methods. The blazar S5 1803+784 has been studied with VLBI at ν = 1.6, 2. 3, 5, 8.4, and 15 GHz between 1993.88 and 2005.68 in 26 observing runs. We (re)analyzed the data and present Gaussian model-fits. We collected the already published kinematic information for this source from the literature and re-identified the components according to the new scenario presented in this paper. Altogether, 94 epochs of observations have been investigated. Results. A careful study of the long-term kinematics reveals a new picture for jet component motion in S5 1803+784. In contrast to previously discussed motion scenarios, we find that the jet structure within 12 mas of the core can most easily be described by the coexistence of several bright jet features that remain on the long-term at roughly constant core separations (in addition to the already known "stationary" jet component ∼1.4 mas) and one faint component moving with an apparent superluminal speed (∼19c, based on 3 epochs). While most of the components maintain long-term roughly constant distances from the core, we observe significant, smooth changes in their position angles. We report on an evolution of the whole jet ridge line with time over the almost 12 years of observations. The width of the jet changes periodically with a period of ∼8−9 years. We find a correlation between changes in the position angle and maxima in the total flux-density light-curves. We present evidence for a geometric origin of the observed phenomena and discuss possible models. Conclusions. We find evidence for a significantly different scenario of jet component motion in S5 1803+784 compared to the generally accepted one of outwardly moving jet components, and conclude that the observed phenomena (evolution of the jet ridge line, roughly constant component core separations but with significant position angle changes) can most easily be explained within a geometric model.

show abstract

Section: Jet Components At Constant Core Separationmentioning

confidence: 99%

The kinematics in the pc-scale jets of AGN

Britzen¹,

Kudryavtseva

Witzel³

et al. 2010

A&A

View full text Add to dashboard Cite

show abstract

“…II C, we write the GRMHD equations in the conservative form. In this case, roughly speaking, there are two options for numerically handling the transport terms [38]. One is to use the Godunov-type, approximate Riemann solver [39,40], and the other is to use the high-resolution central (HRC) scheme [41,20].…”

Section: Numerical Scheme For Solving Grmhd Equationsmentioning

confidence: 99%

Magnetohydrodynamics in full general relativity: Formulation and tests

2005

View full text Add to dashboard Cite

A new implementation for magnetohydrodynamics (MHD) simulations in full general relativity (involving dynamical spacetimes) is presented. In our implementation, Einstein's evolution equations are evolved by a BSSN formalism, MHD equations by a high-resolution central scheme, and induction equation by a constraint transport method. We perform numerical simulations for standard test problems in relativistic MHD, including special relativistic magnetized shocks, general relativistic magnetized Bondi flow in stationary spacetime, and a longterm evolution for self-gravitating system composed of a neutron star and a magnetized disk in full general relativity. In the final test, we illustrate that our implementation can follow winding-up of the magnetic field lines of magnetized and differentially rotating accretion disks around a compact object until saturation, after which magnetically driven wind and angular momentum transport inside the disk turn on.04.25. Dm, 04.40.Nr, 47.75.+f, 95.30.Qd

show abstract

“…In the process, a new set of hydrodynamical variables, namely the conserved variables, are introduced. A particularly common such formulation is the so-called "Valencia" form [28] (see also [29,30] for reviews).…”

Section: A Reference-metric Formulation Of Relativistic Hydrodynamicsmentioning

confidence: 99%

Numerical relativity in spherical polar coordinates: Off-center simulations

Baumgarte¹,

Montero

Müller

2015

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

We have recently presented a new approach for numerical relativity simulations in spherical polar coordinates, both for vacuum and for relativistic hydrodynamics. Our approach is based on a reference-metric formulation of the BSSN equations, a factoring of all tensor components, as well as a partially implicit Runge-Kutta method, and does not rely on a regularization of the equations, nor does it make any assumptions about the symmetry across the origin. In order to demonstrate this feature we present here several off-centered simulations, including simulations of single black holes and neutron stars whose center is placed away from the origin of the coordinate system, as well as the asymmetric head-on collision of two black holes. We also revisit our implementation of relativistic hydrodynamics and demonstrate that a reference-metric formulation of hydrodynamics together with a factoring of all tensor components avoids problems related to the coordinate singularities at the origin and on the axes. As a particularly demanding test we present results for a shock wave propagating through the origin of the spherical polar coordinate system. 04.25.dg, 95.30.Lz, 97.60.Lf

show abstract

Numerical Hydrodynamics in Special Relativity

Cited by 243 publications

References 257 publications

The kinematics in the pc-scale jets of AGN

The kinematics in the pc-scale jets of AGN

Magnetohydrodynamics in full general relativity: Formulation and tests

Numerical relativity in spherical polar coordinates: Off-center simulations

Contact Info

Product

Resources

About