The emission spectra of TeV blazars extend up to tens of TeV and the emission mechanism of the TeV \gamma -rays is explained by synchrotron self-Compton scattering in leptonic models .
In these models the time variabilities of X-rays and TeV \gamma -rays are correlated .
However , recent observations of 1ES 1959+650 and Mrk 421 have found the “ orphan ” TeV \gamma -ray flares , i.e. , TeV \gamma -ray flares without simultaneous X-ray flares .
In this paper we propose a model for the “ orphan ” TeV \gamma -ray flares , employing an inhomogeneous leptonic jet model .
After a primary flare that accompanies flare-up both in X-rays and TeV \gamma -rays , radiation propagates in various directions in the comoving frame of the jet .
When a dense region in the jet receives the radiation , X-rays are scattered by relativistic electrons/positrons to become TeV \gamma -rays .
These \gamma -ray photons are observed as an “ orphan ” TeV \gamma -ray flare .
The observed delay time between the primary and “ orphan ” flares is about two weeks and this is accounted for in our model for parameters such as \Gamma = 20 , d = 4 \times 10 ^ { 17 } cm , \alpha = 3 , and \eta = 1 , where \Gamma is the bulk Lorentz factor of the jet , d is the distance between the central black hole and the primary flare site , \alpha / \Gamma is the angle between the jet axis and the direction of the motion of the dense region that scatters incoming X-rays produced by the primary flare , and \eta / \Gamma is the angle between the jet axis and the line of sight .