Chandra Discovery of an X-Ray Jet and Extended X-Ray Structure in the z = 0.63 Quasar B2 0738+313

We have made a ~30 ks Chandra observation of the redshift z=0.63 gigahertz-peaked spectrum (GPS) quasar B2 0738+313. We detected X-ray emission from the core and have discovered a 200 kpc (projected on the sky) X-ray jet. The X-ray jet is narrow and curves, following the extended radio structure to the south of the quasar, and ending with a hot spot at the southernmost part of the radio lobe. The jet has a knot at ~13" away from the core. The knot emission is consistent with the X-rays being created by the inverse Compton scattering of the cosmic microwave background (CMB) photons and requires jet bulk Lorentz factors of a few (_$(B&#_(Bbulk~5-7). We discuss the emission mechanisms that may be responsible for the jet emission. We present new VLA data of the core and jet, and discuss the relation between the extended radio and X-ray emission. Extended emission observed in several GPS sources has been interpreted as a signature of the source past activity, while the GPS source is young and newly expanded. We argue that B2 0738+313 may be an example of a new class of radio sources similar to the FR II radio galaxies in their high jet bulk velocities, but with a powerful GPS-like nucleus. B2 0738+313 also has two damped Ly_$(B&A_(B systems along the line of sight, at zabs=0.0912 and 0.2212. We discuss the possible connection between the X-ray absorption (7.2+/-0.9ý1020 cm-2) detected in the ACIS spectrum and these two intervening absorbers. We also investigate an extended structure within the central 10" of the core in the relation to structure seen in the optical.