摘要
We studied the optical band periodic variability of 1823+568 using the Jurkevich method,the Lomb-Scargle periodogram and the REDFIT38 software,and found evidence of quasi-periodic oscillation.An unprecedented variability with period P=283^(+17)_(-13) days was identified by three different analysis methods.This quasi-periodic variability most likely results from nonballistic helical jet motion driven by the orbital motion in a binary black hole system.Considering the light-travel time effect,the real physical period is P_(d)=67.1 yr.Moreover,we estimated that the primary black hole mass is M■1.92×10^(9) M_(⊙)to 3.43×10^(9) M_(⊙).
基金
supported by the National Natural Science Foundation of China(NSFC,Grant Nos.12063005,12063006,11863007 and 12063007)
the Program for Innovative Research Team(in Science and Technology)in University of Yunnan Province(IRTSTYN)
Yunnan Local Colleges Applied Basic Research Projects(2019FH001-12,2019FH001-76,202001BA070001-031)。
