RF barrier bucket study

1
RF barrier bucket study

• Outline
• RF barrier bucket issues of the Recycler
• Base line slope between the RF barriers
• Longitudinal e growth due to MI ramping (?)
  
• Longitudinal beam dynamics simulation
• 1-D simulation using ESME

2
Effect of the baseline slope on long. e
non-uniform beam distribution caused by
extra voltage in right side
3
Beam distribution with existing baseline slope
Beam distribution with reduced baseline slope
RF barrier bucket
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Long. e growth due to ramping or RF voltage
in the MI beam inside the RF bucket
wiggles and eventually long. e became
bigger under investigation
5
Beam distribution projected in time sometime
after the injection
Beam distribution projected in time after beam
injection
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Beam simulation using ESME 1. just started,
long way to go 2. simulated a RF bucket with
baseline slope with 6 of RF
voltage result looks qualitatively
right compared to what we observed
7
ESME simulation of the debunching process of RR
Beam injection to the recycler
Decreasing the 2.5 MHz voltage
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Debunched beam contained in the RF bucket
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Simulation of the effect on beam distribution in
phase space with a baseline slope voltage of
the slope is 6 of RF voltage
The beam distribution when 0.45 seconds pass
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3.6 seconds later
4.5 seconds later
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more work on long. e growth issue

• Trying to build a long.e damper system
• - smooth the bump of the beam distribution
  caused by
• external voltage trace the bump of
  the beam
• distribution and put a pulse to the
  opposite direction
• of the external voltage.

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• synchronize the beam signal pass time and a
  electronic
• kick at the right phase.

Resistive Wall Monitor
RF system
13

• ESME simulation of the long.e growth issue is on
  
• the way
• - an alternative way to find out whether the
  long. e growth
• is from MI ramping
• -