Transcript 投影片 1

Injection
Injection Scenario
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2-bumpers local closed orbit method and Lambertson
septum are used for vertical injection.
At the time of injection, circulating beam is bumped
and given a closed orbit towards the septum.
Injection beam at 25 MeV is directed from a linac to
the septum.
The whole beam is bumped back to the center orbit.
Accumulation scheme (phase-space painting) is
adopted.
Injected beam is damped to the center of the
circulating beam through radiation damping.
Repeat until required intensity is needed.
2 Bumpers Local Closed Orbit
Septum
Bumper 1
Bumper 2
 ( s) 2
xco (s) 
i i cos   (s)  i 

2 sin   i 1
Conditionfor localizedclosed orbit :
21  
and
 2  1
1
2
11 cos  21    2  2 cos   0
11 sin   21    2  2 sin    0
How much angular deflection is needed?
Injection Scheme (Accumulation)
 x  1.75
Septum
Total 9 Injections

B
Xco = 25 mm
x
X=0
25mA Linac
Average Beam Current 150mA
1mm
A = 18mm
5mm
4mm
2mm
Location of Bumpers
At thechosenlocationsfor thetwo bumpers:
21  179.3o  
1
1.295

1
2
1.240
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2
T heratioof the:
1
kickers'strength 1
At thechosenlocationfor theseptum:
s1  110o and  s  2m
xco ( septum)  25m m
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Kicker strength:
1   2  19m rad
Location of Bumpers
Location of Bumpers
Length of Septum = 0.2 m
Drift = 2.5 m
Bumper 1
Bumper 2
Bumper Strength
Bumper Strength
Kicker Strength
Due to the possibility of combining the injection and
fast extraction system, traveling wave kicker can
be used.
EL  1 
  1
k 
c  B   
where B  0.0834[Tm]
L  0.1 m
c  speed of light
 1
E  Gap ElectricField
Kicker Strength
x co  9 mm : k  7mrad
 E  8.78[kV / cm]
x co  25 mm :  k  12mrad  E  23.0 [kV / cm]
Micrometerbeam size
 gap  1 cm
 Vgap  8 ~ 23 kV
Vgap can be reduced by using longer kicker
Kicker Strength
Septum Field Strength
Lambertson Septum is used for vertical injection.
z
Injection Beam
s
0.81m

1.15m
L=0.2m
 0.81
o
  tan 

0
.
614
rad
or
35
.
2

 1.15 
1
Septum Field Strength
Bx  L

B
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Bx  0.26 T
25 MeV Injection