Beam life time study for low energy run M. Blaskiewicz, M. Bai, A. - - PowerPoint PPT Presentation

▶

Jul 04, 2023 363 likes •668 views

Beam life time study for low energy run M. Blaskiewicz, M. Bai, A. Fedotov, W. Fisher, M. Minty, G. Wang May 6 th , 2010 Plan Verify intensity dependant beam loss in yellow ring. Verify space charge effects via octopoles in blue

SLIDE 1

Beam life time study for low energy run

M. Blaskiewicz, M. Bai, A. Fedotov,
W. Fisher, M. Minty, G. Wang…

May 6th, 2010

SLIDE 2

Plan

Verify intensity dependant beam loss in

yellow ring.

Verify space charge effects via octopoles in

blue ring.

SLIDE 3

Yellow beam life time study

SLIDE 4

Initial sharp decay with lower injected intensity. Beam Decay v.s. Beam Intensity (WCM.bunched)

SLIDE 5

Low intensity: 0.5E10 (total intensity for 23 bunches )

SLIDE 6

High intensity: 1.5E10 (total intensity for 23 bunches )

SLIDE 7

Beam Decay v.s. Vertical Emittance DA?

SLIDE 8

Beam Decay v.s. Horizontal Emittance DA?

SLIDE 9

Injected with

ctopole at -8.5

Set octopole to 0 Injected with

ctopole at 0

Blue beam life time study

SLIDE 10

Beam intensity

Where we start adjusting octopoles

SLIDE 11

Where we start adjusting octopoles

Blue beam life time study

SLIDE 12

Beam Decay

Change octopoles from -8.5 to -4.5 Change octopoles from -4.5 to 0 Lower Qx to where it was

SLIDE 13

Blue horizontal tune

SLIDE 14

Correlation of beam decay vs. Qx

SLIDE 15

Blue vertical tune

SLIDE 16

Correlation of beam decay vs. Qy

SLIDE 17

Summary

Yellow beam loss was correlated with beam intensity for the

analyzed 7 sets of ‘good’ data.

For injection with low intensity (0.2E9/bunch) , an initial fast

beam decay lasted for ~1 minute.

The effects of octopoles to blue beam life time is not conclusive

as tune/chrom were also changed when adjusting octoples’

strengthes. However, some of the observation might be

explained by the compensation of space charge incoherent tune spread with octopoles.

We did not observe coherent line from low frequency schottky

spectrum and the space charge effects remains unclear.

SLIDE 18

Back up slides

SLIDE 19

SLIDE 20

Beam Decay v.s. Beam Intensity (DCCT)

SLIDE 21

Beam Decay v.s. Beam Intensity (WCM.bunched)

SLIDE 22

Beam Decay v.s. Horizontal Emittance

SLIDE 23

Beam Decay v.s. Vertical Emittance

SLIDE 24

SLIDE 25

Beam Decay v.s. Beam Intensity (WCM.bunched) Initial sharp decay for injections with lower intensity.

SLIDE 26

SLIDE 27

SLIDE 28

Beam Decay v.s. Beam Intensity (DCCT)

SLIDE 29