The role of Kelvin-Helmholtz instability in the internal structure of relativistic outflows. The case of the jet in 3C 273

Context. Relativistic outflows represent one of the best-suited tools to probe the physics of AGN. Numerical modelling of internal structure of the relativistic outflows on parsec scales provides important clues about the conditions and dynamics of the material in the immediate vicinity of the central black holes in AGN. Aims. We investigate possible causes of the structural patterns and regularities observed in the parsec-scale jet of the well-known quasar 3C 273. Methods. We present here the results from a 3D relativistic hydrodynamics numerical simulation based on the parameters given for the jet by Lobanov & Zensus (2001, Science, 294, 128), and one in which the effects of jet precession and the injection of discrete components have been taken into account. We compare the model with the structures observed in 3C 273 using very long baseline interferometry and constrain the basic properties of the flow. Results. We find growing perturbation modes in the simulation with similar wavelengths to those observed, but with a different set of wave speeds and mode identification. If the observed longest helical structure is produced by the precession of the flow, longer precession periods should be expected. Conclusions. Our results show that some of the observed structures could be explained by growing Kelvin-Helmholtz instabilities in a slow moving region of the jet. However, we point towards possible errors in the mode identification that show the need of more complete linear analysis in order to interpret the observations. We conclude that, with the given viewing angle, superluminal components and jet precession cannot explain the observed structures.

[1]  M. Perucho,et al.  Nonlinear stability of relativistic sheared planar jets , 2005, astro-ph/0510426.

[2]  R. Walker,et al.  Modeling the 3C 120 Radio Jet from 1 to 30 Milliarcseconds , 2004, astro-ph/0410720.

[3]  J. Martí,et al.  Stability of hydrodynamical relativistic planar jets - II. Long-term nonlinear evolution , 2004, astro-ph/0407574.

[4]  J. Martí,et al.  Stability of hydrodynamical relativistic planar jets. I. Linear evolution and saturation of Kelvin-Helmholtz modes , 2004, astro-ph/0407548.

[5]  J. Véran,et al.  60 Milliarcsecond Near‐Infrared Imaging of 3C 273 with Altair and Gemini , 2004 .

[6]  P. Hardee,et al.  Internal structure and dynamics of the kiloparsec-scale jet in M87 , 2003 .

[7]  P. Hardee.  Modeling Helical Structures in Relativistic Jets , 2003, astro-ph/0307400.

[8]  S. Iguchi,et al.  A Helical Magnetic Field in the jet of 3C 273(Session 1:Astrophysical Jets,High-Energy Emission from Accreting Compact Objects,Korea-Japan Seminar) , 2002, astro-ph/0205497.

[9]  P. Hardee,et al.  The Effect of External Winds on Relativistic Jets , 2002, astro-ph/0209593.

[10]  M. Hardcastle,et al.  PARTICLES AND FIELDS IN RADIO GALAXIES , 2002 .

[11]  A. Lobanov,et al.  A Cosmic Double Helix in the Archetypical Quasar 3C273 , 2001, Science.

[12]  R. Perley,et al.  HST optical spectral index map of the jet of 3C 273 , 2001, astro-ph/0104393.

[13]  C. Urry,et al.  Chandra Observations of the X-Ray Jet of 3C 273 , 2001, astro-ph/0101299.

[14]  J Korea,et al.  The Magnetohydrodynamic Kelvin-Helmholtz Instability: A Three-dimensional Study of Nonlinear Evolution , 2000, astro-ph/0008084.

[15]  D. A. Schwartz,et al.  Structure of the X-Ray Emission from the Jet of 3C 273 , 2000, astro-ph/0012162.

[16]  P. Hardee.  On Three-dimensional Structures in Relativistic Hydrodynamic Jets , 2000 .

[17]  H. Hirabayashi,et al.  Imaging and monitoring the parsec-scale jet in 3C 273 with the VSOP mission , 2000 .

[18]  Paul S. Smith,et al.  Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei , 1999, astro-ph/9911476.

[19]  A. Lobanov,et al.  Spectral Evolution of the Parsec-Scale Jet in the Quasar 3C 345 , 1999 .

[20]  E. Muller,et al.  GENESIS: A High-Resolution Code for Three-dimensional Relativistic Hydrodynamics , 1999, astro-ph/9903352.

[21]  P. Hardee,et al.  Effects of Magnetic Fields on Mass Entrainment of Supermagnetosonic Jets , 1999 .

[22]  T. Courvoisier.  The bright quasar 3C 273 , 1998, astro-ph/9808147.

[23]  A. Lobanov.  Spectral distributions in compact radio sources I. Imaging with VLBI data , 1998, astro-ph/9804112.

[24]  P. Hardee,et al.  Dynamics and Structure of Three-dimensional Poloidally Magnetized Supermagnetosonic Jets , 1997, astro-ph/9703098.

[25]  A. Frank,et al.  The MHD Kelvin-Helmholtz Instability. II. The Roles of Weak and Oblique Fields in Planar Flows , 1997, astro-ph/9701044.

[26]  A. Lobanov,et al.  Spectral imaging: Shock fronts and plasma instabilities , 1997 .

[27]  Antonio Marquina,et al.  Morphology and Dynamics of Relativistic Jets , 1997 .

[28]  A. Frank,et al.  The Magnetohydrodynamic Kelvin-Helmholtz Instability: A Two-dimensional Numerical Study , 1995, astro-ph/9510115.

[29]  C. Mackay,et al.  Internal structure and polarization of the optical jet of the quasar 3C273 , 1993, Nature.

[30]  J. Tonry,et al.  A redshift survey of IRAS galaxies. VII - The infrared and redshift data for the 1.936 Jansky sample , 1992 .

[31]  R. Davis,et al.  Large-scale superluminal motion in the quasar 3C273 , 1991, Nature.

[32]  M. Birkinshaw.  The Kelvin–Helmholtz instability for relativistic particle beams – II. Flows bounded by a simple shear layer , 1991 .

[33]  M. Cohen,et al.  The Milliarcsecond Structure of 3C 273 at 22 GHz , 1990 .

[34]  M. Cohen,et al.  The inner radio jet of 3C273 , 1988, Nature.

[35]  P. Hardee.  Spatial Stability of Jets: The Nonaxisymmetric Fundamental and Reflection Modes , 1987 .

[36]  S. Unwin.  Superluminal motion in the quasar 3C 279 , 1989 .

[37]  P. Hardee.  Helical twisting on an adiabatically expanding jet. II - Spatial growth , 1986 .

[38]  Walter Kieran Gear,et al.  Models for high-frequency radio outbursts in extragalactic sources, with application to the early 1983 millimeter-to-infrared flare of 3C 273. , 1985 .

[39]  R. Simon,et al.  VLBI monitoring of the superluminal quasar 3C 273, 1977-1982 , 1985 .

[40]  P. Hardee.  Helical twisting on an adiabatically expanding jet. I Propagation and temporal growth , 1984 .

[41]  Martin J. Rees,et al.  Theory of extragalactic radio sources , 1984 .

[42]  R. Davis,et al.  Radio jet of 3C273 , 1981, Nature.

[43]  S. C. Unwin,et al.  Superluminal expansion of quasar 3C273 , 1981, Nature.

[44]  A. Marscher,et al.  Relativistic jets and the continuum emission in QSOs , 1979 .

[45]  A. Shimmins,et al.  Investigation of the Radio Source 3C 273 By The Method of Lunar Occultations , 1963, Nature.

[46]  M. Schmidt,et al.  3C 273 : A Star-Like Object with Large Red-Shift , 1963, Nature.

[47]  P. B. Fellgett,et al.  Vistas in astronomy , 1957 .