Centripetal Transverse Wakefield in Relativistic Beam

The effect of the transverse self-force in a relativistic beam has been studied in the earlier paper of the author [1]. However, the analysis of [1] missed an important observation and has lead to an incorrect estimate of the emittance growth of the beam when it passes through a long bending magnet. Here we correct that analysis. In particular, we conclude that the emittance growth due to the transverse self-force in a long bend is always much smaller than the emittance growth due to the longitudinal coherent synchrotron radiation (CSR) wake.