NORTHERN ILLINOIS CENTER NORTHERN ILLINOIS CENTER FOR ACCELERATOR FOR ACCELERATOR AND DETECTOR AND DETECTOR DEVELOPMENT DEVELOPMENT High-Charged Magnetized Beams at FAST-IOTA [MagBeam] Northern Illinois University: A. Fetterman*, C. Marshall*, P . Piot Fermilab: J. Ruan Collaborators at JLab: S. Benson, J. Gubeli, F. Hannon, S. Wang * Graduate students 1
funded proposal to DOE NP • T1: High-charge magnetjzed beam: Some encouraging • Productjon of high-charge ( 1.6 and 3.2 nC) magnetjzed results produced beam during run I, but • characterizatjon of magnetjzatjon poor data quality • Transport + manipulatjon over long beamline including for publication use of locally non-symmetric optjcs • T2: Understanding halo Initially planned for • Explore halo formatjon in magnetjzed beam using a long- run II now moved to dynamical range diagnostjcs (LDRD) run III • T3: New merger concept: Initially planned for • Tests of merger concept combining RF defmector and magnetjc coil proposed by G. Kraffu and A. Hutuon -- run III now moved augmentjng recent test at Cornell. to another facility (DOE approved) 2
Relevance of FAST injector to EIC e- cooling • Similar beam parameters except for a higher peak current /1.6 (OLD) 3
Outcomes and limitations of Run I • Signifjcantly improved bunch charge: • Emission was space-charge-limited • Increasing spot size resulted in bunch charge up to 6 nC • Produced and transported a magnetjzed beam up to the low energy dump: • Characterized magnetjzatjon and other beam parameters • Produced a fmat beam: X118 • Measured associated emituance (which corresponds to the incoming magnetjzed beam eigen emituances) • Limitatjons: • Emituance measurement of eigenemituance could not be X120 +X118H X120 +X118V performed precisely due to movable slit issues • We could not trust the ICT • Laser inhomogeneity 4
Outcomes and Summer Improvements • Issue with single-slit scan was fjxed (Daren, Jinhao) and analysis (Aaron) shows is could be used for emituance measurement • Improved analysis of data is encouraging (analysis from Aaron Fetterman) 5
Simulation using realistic experimental conditions reproduce some of the experimental feature (A. Fetterman et al. NAPAC19) • Optjmizatjon done for idealized laser distributjon • Impact of non-ideal distributjon is explored via simulatjon 9 mm E (MeV) 9 mm 04/02/2019 P. Piot | 2019 JLEIC collaboratjon meetjng, JLab 6
Proposal (phase I: 4 shifts) Mapping through a round to flat beam transformer • Shifu 1: essentjally reproduce settjngs of run 1 (FEB/ MAR): – Vary solenoid and monitor vacuum (processing) – Test all diagnostjcs and especially all the scanning single slits diagnostjcs • Shifus 2-4 (contjguous): 1.6 and 3.2-nC magnetjzed Direct measurement on mag. beam beam characterizatjon – Measure magnetjzatjon, eigen emituances, – Perform parametric studies for a few cases: several laser-spot radii. Ratjo of Bmain and Bbuck – Take data to compare the two eigen-emituance measurement methods Beam termination in low-energy absorber 7
Proposal (phase II: 2 shifts) • Shifu 5-6: beam transport to downstream cryomodule (assuming all data of phase I Flat beam generated using Q441-3 have been collected) quads and observed in the 450 area – Transport through cryomodule (ideally with cryomodule eventually ofg) – Generatjon of a “skew” fmat beam with Q441-3 – Measure beam magnetjzatjon downstream of cryomodule and injector values. – If tjmes allows study propagatjon of magnetjzed beams in a non-locally but globally symmetric beamline !!! Beam termination: not sure on its way to HE dump (is it acceptable with up to 10 bunches (total Q~50 nC over macropulse?) 8
Personnel + TODO list • Hardware: • Shifu personnel: – Shifu 1: local people (NIU – Check CCD focus at slit include A. Fetuerman and P. locatjons [Aaron] Piot) – Deploy/test RCDS algorithm for – Shifu 2, 3, and 4: Jlab personnel fast on-line fmat beams will join (list to be fjnalized once we have possible dates) optjmizatjon [Philippe] – Shifu 5, 6: locals only (TBC) will – Ability to change the laser spot likely include NIU’s C. Marshall, size between 2 to 4 mm (full A. Fetuerman and P. Piot. radius) if not what is possible? – Are the ICTs OK? • Data acquisitjon/analysis – Tools are mostly ready and will enable some preliminary on-line analysis to guide experiment 9
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