The improvement of energy measurement in BTS transport line by using beam tracing method

A method which measures the e^- beam energy in the booster to storage ring transport line is introduced. One of the bending magnets in the BTS transport line is chosen as the reference dipole for the energy measurement. The beam tracing method which takes into account of the fringe field effect is employed to calibrate the I-B curve of the reference dipole to enhance the accuracy of the energy measurement. The desired trajectory of the e^- beam is traced for different energy by adjusting the reference dipole current. The current correction factor with and without this calibration is -0.33% for a 1.3 GeV e^- beam for SRRC. The possible error sources of this measurement are also discussed and estimated