The jet and counterjet of 3C 270 (NGC 4261) viewed in the X-ray with
  Chandra
  The radio source 3C 270, hosted by NGC 4261, is the brightest known example
of counterjet X-ray emission from a low-power radio galaxy. We report on the
X-ray emission of the jet and counterjet from 130 ks of Chandra data. We argue
that the X-ray emission is synchrotron radiation and that the internal
properties of the jet and counterjet are remarkably similar. We find a smooth
connection in X-ray hardness and X-ray to radio ratio between the jet and one
of the X-ray components within the core spectrum. We observe wedge-like
depressions in diffuse X-ray surface brightness surrounding the jets, and
interpret them as regions where an aged population of electrons provides
pressure to balance the interstellar medium of NGC 4261. About 20% of the mass
of the interstellar medium has been displaced by the radio source. Treating 3C
270 as a twin-jet system, we find an interesting agreement between the ratio of
jet-to-counterjet length in X-rays and that expected if X-rays are observed
over the distance that an outflow from the core would have traveled in ~6x10^4
yr. X-ray synchrotron loss times are shorter than this, and we suggest that
most particle acceleration arises as a result of turbulence and dissipation in
a stratified flow. We speculate that an episode of activity in the central
engine beginning ~6x10^4 yr ago has led to an increased velocity shear. This
has enhanced the ability of the jet plasma to accelerate electrons to
X-ray-synchrotron-emitting energies, forming the X-ray jet and counterjet that
we see today.
