Design of the muon accelerator using GPT�Research on the relationship between the Mismatch Factor and Emittance

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高世龙 (GAO Shilong)

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Supervisor: Prof. Otani

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August 6, 2024

中国科学院近代物理研究所

Institute of Modern Physics, Chinese Academy of Sciences

CONTENTS

• self-introduction
• background
• progress

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self-introduction

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Name: 高世龙(GAO shilong)�Title: Ph.D. Student, Year 1�Affiliation: Institute of Modern Physics, Chinese Academy of Sciences�Field: Accelerator Physics and RF Cavity�Contact: gaoshilong@impcas.ac.cn

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Muon linac for the J-PARC muon g-2/EDM experiment

muon H-line

storage magnet

injection

Extension bld.

neutrino

hadron

MLF

KEK gun

buncher 1^st cell

buncher exit

J-PARC IS

RFQ

DTL

SDTL

ACS

Background

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Mismatch ← Main cause of Emittance Change in the muon linac

design

matched �beam

mismatched �beam

X

X‘

• Among several definitions, rms emittance is used.

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• rms emittance depends not only area but also distortion.

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Beam dynamics simulation for the muon LINAC RFQ

Calculate the parameter of the upstream simulation output.

Mismatch factor vs. emittance in generated distribution.

Calculate the upstream simulation output with distortion

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2

3

(TDR distribution)

(latest distribution)

(gauss distribution)

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Task 1

generate input beam distributions

Find the range of Twiss parameters satisfying M<1

Beam dynamics simulation in RFQ by GPT

Investigate M vs Δemittance

M is the mismatch factor

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Task 1

generate input beam distributions

Find the range of Twiss parameters satisfying M<1

Beam dynamics simulation in RFQ by GPT

Investigate M vs Δemittance

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Task 1

generate input beam distributions

Find the range of Twiss parameters satisfying M<1

Beam dynamics simulation in RFQ by GPT

Investigate M vs Δemittance

asci2gdf -o "${INPUT_GDF}" "${INPUT_TXT}"

gpt -s -v -j 32 -o $OUTPUT_GDF run/RFQ_r2.in FILENAME=\"$ INPUT _GDF\"

gdf2a -w 16 -o "${OUTPUT_TXT}" "${OUTPUT_GDF}"

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Task 1

generate input beam distributions

Find the range of Twiss parameters satisfying M<1

Beam dynamics simulation in RFQ by GPT

Investigate M vs Δemittance

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Task 2

Mismatch factor of x 0.4476

Mismatch factor of y 1.1386

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Task 2 transport using the transmission matrix

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Task 2 Parameter range and Results

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Task 3 Distorted distribution

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Task 3 Different results of the two transfer methods

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Task 3

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Result

Y=0.1651x+0.2555

Y=0.2057x+0.1628

Emittance_x_in 21.08

Y=0.1466x+0.1478

Emittance_x_in 16.08

Emittance_x_in 18.63

For the distorted distribution, the emittance will increase even if the mismatch factor is 0

generated Gaussian distribution

real Gaussian distribution

distorted Gaussian distribution

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7.22 7.23 7.24 7.25 7.26

7.15 7.16 7.17 7.18 7.19

Schedule

Online meeting,

Study Linux and GPT

Calculate Twiss and emittance

Calculate mismatch factor

Generate simple particle distribution

Compute by GPT and check for correctness

get the linear relation by generate multiple input distributions

Compute the real distribution

Discover the parameter range of transport matrix

get the linear relation by adjust Twiss

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8.5 8.6 8.7 8.8 8.9

7.29 7.30 7.31 8.1 8.2

Schedule

Summer Student Program Joint Event

Summer Student Program Joint Event

Calculate Twiss and emittance of distorted Gaussian distribution

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Summer Student Program Joint Event

Discover the parameter range and Compute

Prepare for presentation

Organize and document it

Organize and document it

Organize and document it

Discover the parameter range and Compute

thank you for your patience

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高世龙

August 6, 2024

中国科学院近代物理研究所

Institute of Modern Physics, Chinese Academy of Sciences