A Possible $\gamma$-ray Quasi-periodic Oscillation of $\sim$ 314 days in
  the Blazar OJ 287
  We report the detection of a probable $\gamma$-ray quasi-periodic oscillation
(QPO) of around 314 days in the monthly binned 0.1 -- 300 GeV $\gamma$-ray {\it
Fermi}-LAT light curve of the well known BL Lac blazar OJ 287. To identify and
quantify the QPO nature of the $\gamma$-ray light curve of OJ 287, we used the
Lomb-Scargle periodogram (LSP), REDFIT, and weighted wavelet z-transform (WWZ)
analyses. We briefly discuss possible emission models for radio-loud active
galactic nuclei (AGN) that can explain a $\gamma$-ray QPO of such a period in a
blazar. Reports of changes in the position of quasi-stationary radio knots over
a yearly timescale as well as a strong correlation between gamma-ray and
mm-radio emission in previous studies indicate that the signal is probably
associated with these knots.
