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H.L. Marshall, J. C. Lee, P.M. Ogle (MIT CSR), J. J. Drake, A. Fruscione, J. Grimes, D. Harris, R. Kraft, D. Pease, D. Schwartz, A. Siemiginowska, S. Vrtilek, B. Wargelin (SAO)
We present images from four Chandra observations of the quasar 3C 273. The zeroth order images from two grating observations using the ACIS-S detector are used to examine the structure and spectrum of the jet. The jet has at least four distinct features which are not resolved in previous observations (e.g. Roeser et al. 2000, A&A submitted). Using jet feature nomenclature based on HST observations (cf. Bahcall et al. 1995, Ap.J., 452, L91), we find that knot A1 is very bright in X-rays. We have measured the X-ray spectrum of this X-ray knot for the first time, obtaining a photon index of 1.86 +/- 0.11 and a flux density of 37 +/- 4 nJy at 1 keV. Combining this measurement with lower frequency data shows that a pure synchrotron model can fit the spectrum of knot A1 from 4 GHz to 5 keV (over nine decades in energy) without a change of spectral slope.
Knot A2 is also detected and is somewhat blended with knot B1 but synchrotron emission is not likely to explain the X-ray emission due to the spectral turnover observed in the optical-UV band (Roeser et al. 2000). No other knots are clearly detected but there is an indication of weak emission from the eastern portion of knot H3, near the ``head'', which is radio-bright. There is diffuse flux which extends from 14" to 20" which shows curvature that is comparable to the optical flux found by Bahcall et al. (1995).
The dispersed spectra of the core of 3C 273 appears to be devoid of spectral intrinsic absorption edges or emission or absorption lines.
This work was funded in part by contract SAO SV1-61010 and NASA contract NAS8-39073.
The author(s) of this abstract have provided an email address for comments about the abstract: hermanm@space.mit.edu