Looking for ancillary signals around GW150914
  We replicated the procedure in Liu and Jackson (arXiv:1609.08346), who had
found evidence for a low amplitude signal in the vicinity of GW150914. This was
based upon the large correlation between the time integral of the Pearson
cross-correlation coefficient in the off-source region of GW150914, and the
Pearson cross-correlation in a narrow window around GW150914, for the same time
lag between the two LIGO detectors as the gravitational wave signal. Our
results mostly agree with those in arXiv:1609.08346. We find the statistical
significance of the observed cross-correlation to be about 2.5 $\sigma$. We
also used the cross-correlation method to search for short duration signals at
all other physical values of the time lag, within this 4096 second time
interval, but do not find evidence for any statistically significant events in
the off-source region.
