SIMBAD references

In this paper, the long-term historical optical (UBVRI) and near-infrared (JHK) data are presented with some new observations in the optical (February 1994-January 1995) and near-infrared (November 1995) bands included for BL Lac object OJ 287. The new optical data in V-band are in agreement with the results reported by other authors (Sillanpaa et al., 1996, ASP Conf. Ser. 110, 74; Arimoto et al., 1997PASP..109..300A), a close correlation between the color index of B-V and the magnitude V has been obtained from our new observations. The new infrared observations presented here indicate that the source was at a high level in the infrared band during the observation period. From the available literature, we have got that the largest variations for UBVRIJHK bands are respectively: ΔU=4.72mag ; ΔB=5.93mag; ΔV=5.18mag; ΔR=4.45mag; ΔI=4.07mag; ΔJ=3.87mag; ΔH=3.78mag; ΔK=3.54mag. A strong correlation is found between the optical and near-infrared bands when the DCF method is used, which suggests that these two bands have the same emission mechanism.