Equation Icon   m-c v V~ --------m-c x e V~ -------2 . \~/ xf - 1 + |v|2e mr --. \~/ vf = 0, (47) 1 + |v| r e-2c(2rcr - 1) + 1 = 8pr2r, (48) -2c 2 e (2rmr + 1) - 1 = 8pr p. (49)