Abstract
Recent radio, optical and near-infrared observations of the dominant hotspot at the outer end of the quasar jet 3C273A have revealed a complex spectrum, significantly different from a simple power law, which provides a unique probe of the acceleration process supplying the synchrotron-emitting electrons. Here we present theoretical calculations of the electron spectrum produced by non-relativistic shock acceleration which, for the first time, include both synchrotron losses and a finite emission region. The resultant synchrotron spectrum fits the observations, providing a natural explanation for the steep spectrum at radio to infrared frequencies, the observed flattening at ν < νb = 1.5 GHz, and the cutoff above νc = 2 × 1014 Hz. Our model yields a new magnetic field estimate of 70 nT, remarkably similar to that derived from minimum-energy calculations, as well as an estimate for the electron mean free path. We predict that the optical emission region is only ∼1 pc thick, increasing with decreasing observation frequency as ν−1/2.
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References
Conway, R. G., Davis, R. J., Foley, A. R. & Ray, T. P. Nature 294, 540–542 (1981).
Perley, R. A. Proc. IAU Symp. 110, 153–156 (1984).
Flatters, C. & Conway, R. G. Nature 314, 425–426 (1985).
Foley, A. R. & Davis, R. J. Mon. Not. R. astr. Soc. 216, 679–690 (1985).
Davis, R. J., Muxlow, T. W. B. & Conway, R. G. Nature 318, 343–345 (1985).
Röser, H.-J. & Meisenheimer, K. Astr. Astrophys. 154, 15–24 (1986).
Henry, J. P., Becklin, E. E. & Telesco, C. M. Astrophys. J. 280, 98–101 (1984).
Wilson, M. J. & Scheuer, P. A. G. Mon. Not. R. astr. Soc. 205, 449–463 (1983).
Smith, M. D., Norman, M. L., Winkler, K.-H. & Smarr, L. Mon. Not. R. astr. Soc. 214, 67–85 (1985).
Bell, A. R. Mon. Not. R. astr. Soc. 182, 147–156 (1978).
Blandford, R. D. AIP Conf. Proc. No. 56, 333–350 (1979).
Heavens, A. F. thesis, Cambridge Univ. (1983).
Webb, G. M., Drury, L. O'C. & Biermann, P. Astr. Astrophys. 137, 185–201 (1984).
Drury, L. O'C. Rep. Progr. Phys. 46, 973–1027 (1983).
Longair, M. S. High Energy Astrophysics (Cambridge University Press, 1981).
Laing, R. A. Mon. Not. R. astr. Soc. 193, 439–449 (1980).
Pearson, T. J. et al. Nature 290, 365–368 (1981).
Benson, J. M. & Walker, R. C. Proc. IAU Symp. 110, 125–126 (1984).
Bridle, A. H. in Proc. NRAO Workshop No. 9, 135–143 (1984).
Laing, R. A. in Proc. NRAO Workshop No. 9, 90–98 (1984).
Burn, B. J. Mon. Not. R. astr. Soc. 133, 67–83 (1966).
Heavens, A. F. & Meisenheimer, K. Mon. Not. R. astr. Soc. (submitted).
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Meisenheimer, K., Heavens, A. Particle acceleration in the hotspot of the jet of quasar 3C273. Nature 323, 419–422 (1986). https://doi.org/10.1038/323419a0
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DOI: https://doi.org/10.1038/323419a0
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