19.3yr R-band monitoring of 1ES 2344+514

The following conclusions are drawn: (1) A variability of {Delta}R=0.155mag (15.356-15.201mag) over a timescale of {Delta}T=12.99min is detected during our 628d of monitoring. (2) According to the Kelvin-Helmholtz thermal instability, if the magnetic field intensity (B) for the source is greater than a critical value (B_c_), it will reduce the incidence of intraday variations in the light curves. (3) The physical parameters of the dissipation region are obtained by fitting the spectral energy distribution with a one-zone synchrotron self-Compton model for the average and flare states.

(4) The three methods show that there are periods of P=2.72+/-0.47yr, P=1.61+/-0.18yr, P=1.31+/-0.17yr, and P=1.05+/-0.07yr. When a binary black hole system is adopted with a period of P=2.72+/-0.41yr, we obtain the orbital parameters for the binary black hole system as follows: M=8.08x10^9^M_{sun}_, the sum of the semiaxes is r=7.18x10^16^cm, and the lifetime of the binary black hole is {tau}_merge_=6.24x10^2^yr.