1. Perturbation of Focusing Field Profile due to HV Support Tube

2. Poisson Field Profile for Tunnel Gun Geometry
Focusing center (cathode center) is located at
x = 8.89cm .
Focusing electric field is 0V/cm at focusing center.
Focusing center should be constant from cathode to anode

3. Focusing E-field profile for Tunnel Geometry
Focusing center is constant from cathode to anode

4. Poisson Field Profile for Load lock Geometry
Added HV tube to the right

5. Focusing E-field profile for Load Lock Geometry
Focusing center changes from cathode to anode

6. Conclusion
Model shows focusing field is perturbed by introducing the side HV tube
Experimental test required to see how much of an effect this perturbation has on beam dynamics