A turbulent model for the surface brightness of extragalactic jets

L. Zaninetti

Dipartimento di Fisica Generale, Via Pietro Giuria 1, 10125 Torino, Italy. (zaninetti@ph.unito.it).

Received 2007 October 3
Accepted 2008 September 25

RESUMEN

En este artículo se resume la física conocida sobre los chorros turbulentos observados en experimentos de laboratorio. La fórmula para la potencia liberada como turbulencia describe la concentración turbulencia/partículas relativistas en cada punto del chorro astrofísico. Se usa la misma expresión para analizar la potencia liberada como turbulencia para fluidos de tubo y no–newtonianos. Mediante una operación integral es posible deducir la intensidad de la radiación sincrotrónica para un perfil perpendicular (o no) a un chorro recto, obtener un mapa 2D para un chorro perpendicular de orientación arbitraria, así como mapas 2D para trayectorias complejas como es el caso de NGC 4061 y 3C31. Se presenta una simulación del índice espectral del brillo para 3C273, así como un mapa 2D del grado de polarización lineal. Se aplica el operador Sobel a los mapas 2D teóricos para chorros rectos perpendiculares.

ABSTRACT

This paper summarizes the known physics of turbulent jets observed in laboratory experiments. The formula, which gives the power released in turbulence describes the concentration of turbulence/relativistic particles in each point of the astrophysical jets. The same expression is also used to analyze the power released in turbulence in the case of pipe and non–Newtonian fluids. Through an integral operation it is possible to deduce the intensity of synchrotron radiation for a profile perpendicular (or not) to a straight jet, a 2D map for a perpendicular, randomly oriented straight jet, as well as a 2D map of complex trajectories such as NCC 4061 and 3C31. Presented here is a simulation of the spectral index in brightness of 3C273 as well as a 2D map of the degree of linear polarization. The Sobel operator is applied to the theoretical 2D maps of straight perpendicular jets.

Key Words: galaxies: jets — radio continuum: galaxies.

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REFERENCES

Abramowitz, M., & Stegun, I. A. 1965, Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables (New York: Dover)        [ Links ]

Bicknell, G. V. 1984, ApJ, 286, 68        [ Links ]

Bird, R., Stewart, W., & Lightfoot, E. 2002, Transport Phenomena (2nd ed., New York: John Wiley and Sons)        [ Links ]

Bravo, L. 2006, PhD Thesis, The City University of New York         [ Links ]

Bridle, A. H., Henriksen, R. N., Chan, K. L., Fomalont, E. B., Willis, A. G., & Perley, R. A. 1980, ApJ, 241, L145        [ Links ]

Burn, B. J. 1975, A & A, 45, 435        [ Links ]

Canvin, J. R., & Laing, R. A. 2004, MNRAS, 350, 1342        [ Links ]

Eilek, J., Hardee, P., & Lobanov, A. 2003, NewA Rev., 47, 505        [ Links ]

Falle, S. A. E. G. 1994, MNRAS, 269, 607        [ Links ]

Favre, A. 1969, in Problems of Hydrodynamics and Continuum Mechanics (Philadelphia: SIAM), 231        [ Links ]

Fermi, E. 1949, Phys. Rev., 75, 1169        [ Links ]

Ferrari, A., Trussoni, E., & Zaninetti, L. 1979, A & A, 79, 190         [ Links ]

Ginsburg, V. 1975, Physique Teorique et Astrophysique (Moscow: Editions MIR)         [ Links ]

Hughes, W., & Brighton, J. 1967, Fluid Dynamics (New York: McGraw–Hill)         [ Links ]

Hussein, H. J., Capp, S. P., & George, W. K. 1994, Journal of Fluid Mechanics, 258, 31         [ Links ]

Jester, S., Harris, D. E., Marshall, H. L., & Meisenheimer, K. 2006, ApJ, 648, 900         [ Links ]

Jester, S., Meisenheimer, K., Martel, A. R., Perlman, E. S., & Sparks, W. B. 2007, MNRAS, 380, 828         [ Links ]

Kundt, W. 1979, Ap & SS, 62, 335         [ Links ]

––––––––––. 2006, Chinese J. Astron. Astrophys. Suppl., 6, 279         [ Links ]

Kundt, W., & Gopal Krishna. 2004, J. Astrophys. Astr., 25, 115         [ Links ]

Laing, R. A., & Bridle, A. H. 2002a, MNRAS, 336, 328         [ Links ]

––––––––––. 2002b, MNRAS, 336, 1161        [ Links ]

Laing, R. A., Canvin, J. R., & Bridle, A. H. 2005, in X–Ray and Radio Connections, ed. L.O. Sjouwerman and K. K. Dyer, published electronically by NRAO (arXiv:astro–ph/0405020v1)         [ Links ]

Laing, R. A., Canvin, J. R., Bridle, A. H., & Hardcastle, M. J. 2006, MNRAS, 372, 510         [ Links ]

Lang, K. R. 1999, Astrophysical Formulae (3th ed., New York: Springer)         [ Links ]

Lobanov, A., Hardee, P., & Eilek, J. 2005, in ASP Conf. Ser. 340, Future Directions in High Resolution Astronomy, ed. J. Romney & M. Reid (San Francisco: ASP), 104        [ Links ]

Lobanov, A. P., & Zensus, J. A. 2001, Science, 294, 128         [ Links ]

Nishikawa, K.–I., Hardee, P. E., Hededal, C. B., & Fishman, G. J. 2006, ApJ, 642, 1267         [ Links ]

Noriega Crespo, A., Garnavich, P. M., Raga, A. C., Canto, J., & Boehm, K.–H. 1996, ApJ, 462, 804         [ Links ]

Pelletier, G., & Zaninetti, L. 1984, A & A, 136, 313         [ Links ]

Perlman, E. S., & Wilson, A. S. 2005, ApJ, 627, 140         [ Links ]

Pope, S. B. 2000, Turbulent Flows (Cambridge: Cambridge Univ. Press)         [ Links ]

Pratt, W. 1991, Digital Image Processing (New York: Wiley)        [ Links ]

Research and Education Association (REA) 1985, Transport Phenomena Problem Solver (Piscataway: REA)        [ Links ]

Rybicki, G., & Lightman, A. 1985, Radiative Processes in Astrophysics (New York: Wiley Interscience)        [ Links ]

Schlichting, H., Gersten, K., Krause, E., & Oertel, H. J. 2004, Boundary Layer Theory (New York: Springer)        [ Links ]

Thompson, W. J. 1997, Atlas for Computing Mathematical Functions (New York: Wiley Interscience)        [ Links ]

von Seggern, D. 1992, CRC Standard Curves and Surfaces (New York: CRC)        [ Links ]

Worrall, D. M., Birkinshaw, M., Laing, R. A., Cotton, W. D., & Bridle, A. H. 2007, MNRAS, 380, 2        [ Links ]

Zaninetti, L. 1989, A & A, 223, 369        [ Links ]

––––––––––. 1999, J. Comput. Phys., 156, 382        [ Links ]

––––––––––. 2007, RevMexAA, 43, 59        [ Links ]