When we simply reduce BC2 energy, Here is a smaller chirper, but with a larger horn (that can be easily reduced with optimization) UNDBEG Energy at BC2= 5GeV; final beam energy=3.5GeV Energy at BC2=3. 5GeV; final beam energy=3.5GeV E-Jitter 0.076% E-Jitter=0.044%

Global optimization for SXR L1 Phase LX Phase -149 L2 Phase -16 R56 BC mm LX Voltage 33.8MV R56BC mm L3 Phase BC2 Energy 3GeV Final beam energy 3.5GeV Solution1: E-jitter 0.021%

optimization with constrains VLX_max=23MV, solution8 L1 Phase LX Phase L2 Phase R56 BC mm LX Voltage 23MV R56BC mm L3 Phase -12 E-Jitter=0.026% 40% reductions compared with BC2 energy change only 0.044% Still larger horn compared with nominal ~zero chirper

Smaller E-jitter with a larger R56 L1 Phase LX Phase L2 Phase -16 R56 BC mm LX Voltage 23MV R56BC mm L3 Phase -5 E-Jitter=0.020% Larger

Energy at BC2 5GeV Ipk=1.7kA L1 Phase -27 LX Phase -160 L2 Phase -22 R56 BC mm LX Voltage 23MV R56BC mm L3 Phase 0 E-Jitter=0.022% LX Voltage 23MV Final Beam energy=5.5GeV L3 Phase=0

Ebeam 4.0GeV R56BC2_new=50mm L3 phase=-180, Jitter=0.03%