8th HEAD Meeting, 8-11 September, 2004
Session 4 Jets and Blazars
Poster, Wednesday, September 8, 2004, 9:00am-10:00pm

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[4.23] A Chandra Snapshot Survey of Radio-Loud Quasars at High Redshift

L. A. Lopez, W. N. Brandt, D. P. Schneider (Penn State), C. Vignali (INAF), G. P. Garmire (Penn State)

We present the results of Chandra ACIS-S "snapshot" observations of six radio-loud quasars (RLQs) at z \approx 3.5-4.7. These observations sample luminous RLQs with moderate-to-high radio-loudness (R \approx 200-9600) and aim to connect the properties of radio-quiet (R < 10) and highly radio-loud blazars (R > 1000) at high redshift. This work extends a previous study by Bassett et al. (2004) which used similar methods to examine RLQs with moderate radio-loudness (R \approx 40-400). We determine the X-ray luminosities of our targets and compare their broad-band spectral energy distributions (e.g., \alphaox and \alpharx) with those of local RLQs. We measure the X-ray continuum shape to search for intrinsic X-ray absorption via individual and joint X-ray spectral fitting. Finally, we look for evidence of extended X-ray emission that may be associated with radio jets (e.g., Schwartz 2002). In the inverse-Compton model, high-redshift radio jets are predicted to be strong X-ray emitters as a result of increased energy density of Comsic Microwave Background seed photons. Bassett et al. (2004) found no spatial detections of X-ray jets nor enhancement of the X-ray emission relative to comparable RLQs at low-to-moderate redshift. With the new Chandra observations presented here, we test this result as a means to help elucidate the mechanisms of X-ray production in high-redshift RLQs.

The author(s) of this abstract have provided an email address for comments about the abstract: lalopez@mit.edu

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Bulletin of the American Astronomical Society, 36 #3
© 2004. The American Astronomical Soceity.