We present a kinematic study of the parsec-scale radio jet in OJ 287, one of the most studied BL Lac objects, during γ-ray ares, to explore the relation between parsec-scale radio jet activity and γ-ray emission. The 22-GHz light curve of OJ 287 show three obvious are events around 2011 May, 2011 October, and 2012 March. The second radio are occurred during the γ-ray aring period, and the third radio are seemed to precede the γ-ray are by one month. One jet component moved outward with respect to the core component with an apparent superluminal speed (~ 11c) from 2010 November to 2011 November. Then it changed direction, moving apparently inward in 2011 November, when the γ-ray are occurred. The observed apparent inward motion of the jet at 22 GHz could be caused by a new jet component, unresolved at 22 GHz, in the innermost region.

ABSTRACT
1. INTRODUCTION
2. OBSERVATIONS AND DATA REDUCTIONS
3. RESULTS
    3.1. Parsec-scale Structure
    3.2. Radio and γ-ray Light Curves
    3.3. Radio Jet Motion
4. DISCUSSION
5. CONCLUSIONS
REFERENCES

• K. M. Shibata(NAOJ)
• M. Honma(NAOJ)
• M. Orienti(INAF Istituto di Radioastronomia)
• K. Hada(NAOJ)
• S. Koyama(Max-Planck-Institut fur Radioastronomie)
• F. D'Ammando(INAF Istituto di Radioastronomia)
• M. Kin(KASI)
• H. Nagai(NAOJ)
• K. Niinuma(Yamaguchi University)
• K. Akiyama(The University of Tokyo/NAOJ)
• S. Sawada-Satoh(Mizusawa VLBI Observatory, NAOJ)