  High-frequency iron K reverberation lags, where the red wing of the line
responds before the line centroid, are a robust signature of relativistic
reflection off the inner accretion disc. In this letter, we report the
discovery of the Fe K lag in PG 1244+026 from ~120 ks of data (1 orbit of the
XMM-Newton telescope). The amplitude of the lag with respect to the continuum
is 1000 s at a frequency of ~1e-4 Hz. We also find a possible
frequency-dependence of the line: as we probe higher frequencies (i.e. shorter
timescales from a smaller emitting region) the Fe K lag peaks at the red wing
of the line, while at lower frequencies (from a larger emitting region) we see
the dominant reflection lag from the rest frame line centroid. The mean energy
spectrum shows a strong soft excess, though interestingly, there is no
indication of a soft lag. Given that this source has radio emission and it has
little reported correlated variability between the soft excess and the hard
band, we explore one possible explanation in which the soft excess in this
source is dominated by the steep power-law like emission from a jet, and that a
corona (or base of the jet) irradiates the inner accretion disc, creating the
blurred reflection features evident in the spectrum and the lag. General
Relativistic ray-tracing models fit the Fe K lag well, with the best-fit giving
a compact X-ray source at a height of 5 gravitational radii and a black hole
mass of 1.3e7 Msun.
