Thesis work

Thesis Outline

1. Introduction

• Magnetized electron beam
• Applications of the magnetized electron beam

    * Magnetized electron cooling

• Jefferson Lab magnetized electron source for the JLEIC cooler

1. Generation of the magnetized electron beam
   1. Experimental setup (DC HV gun, photo cathode, RF laser, solenoid, etc.)
   2. Beam diagnostics

Beam dynamics

Beam matrix Phase space Emittance (thermal, phase space, geometric) Effective(drift) emittance (emittance of the magnetized beam) Measuring the beam emittance

Space charge effect

Space charge effect in the magnetized beam

Simulations on the magnetized electron beam

ASTRA Initial particle distribution Field maps (3D E field map, 2D B field map) Space charge calculation mechanism Emittance GPT Initial particle distribution (Laser*QE image processing) Field maps (3D E field map, 2D B field map) Space charge calculation mechanism Emittance Post-processing (MATLAB)

Characterization of the magnetized beam

Experimental method Beam size vs solenoid I Rotation angle vs solenoid I Emittance vs solenoid I - two different laser sizes Emittance vs laser spot sizes - max solenoid current ASTRA/GPT simulations (Simulation of all the above variations) Conclusions (comparisons -measurements vs simulations, mismatch oscillations, negative rotation angles, etc.)

7 Experiments a

Headline text

nd numerical simulations of the space charge dominated magnetized beam Experimental methods Pulse energy vs extracted charge -for different magnetizations Space charge current limitation dependence on gun high voltage- for different magnetizations Space charge current limitation dependence on pulse width- for different magnetizations Space charge current limitation dependence on laser spot size- for different magnetizations GPT simulations Conclusions (Comparison -measurements and simulations) …

Redesiging and performance of the photogun

Gun designing CST electrostatic design GPT simulations implementing the new gun field map Polishing and gun assembly High voltage conditioning

Conclusions

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