Fig. 1. Magnet layout and linear optical parameters of one period HALF lattice
Fig. 2. Dynamic aperture of the HALF storage ring
Fig. 3. Schematic layout of injection devices for the bump injection scheme with anti-septum (K2)
Fig. 4. Element layout of anti-septum injection scheme
Fig. 5. Position of the first six turns of injection beam
Fig. 6. Injection efficiency of anti-septum injection scheme
Fig. 7. Influence of anti-septum injection on the stored beam
Fig. 8. Schematic layout of injection devices for the multipole kicker injection scheme
Fig. 9. Field distribution of nonlinear kicker
Fig. 10. First turn trajectory of the injection particle and specific parameters of the injection scheme
Fig. 11. Accumulation process after pulsed multipole injection
Fig. 12. Injection efficiency of pulsed multipole injection with error
Fig. 13. Influence of pulsed multipole injection on the stored beam
Fig. 14. Schematic layout of injection devices for the longitudinal injection scheme
Fig. 15. Upper and lower boundaries of longitudinal phase space in longitudinal injection
Fig. 16. δ0 and δs change with high frequency cavity voltage
Fig. 17. Accumulation process of injection beam in longitudinal injection
circumference/
m
| beam
energy/
GeV
| focusing
type
| natural
emittance/
(pm·rad)
| transverse
tunes
(H/V)
| natural
chromaticities
(H/V)
| momentum
compaction
factor
| energy
loss per
turn/keV
| harmonic
number
| RF
frequency/
MHz
| RF
voltage/
kV
| damping
time
(H/V/L)/ms
| natural
energy
spread
| 479.86 | 2.2 | 20×6BA | 86.3 | 48.15/17.15 | −77/−57 | 9.0×10−5 | 186.7 | 800 | 500 | 1000 | 27.2/37.7/23.4 | 0.62×10−3 |
|
Table 1. Main parameters of the HALF storage ring
horizontal position
of the injection beam
at septum/mm
| incidence angle of
the injection beam
at septum/mrad
| position
of
septum
| position of
nonlinear
kicker
| length of
nonlinear
kicker/cm
| kick angle of
nonlinear
kicker/mrad
| 12 | −3.1 | midpoint of long
straight section
| downstream of long
straight section
| 40 | 3 |
|
Table 2. Main parameters of pulsed multipole injection scheme
injection beam time offset/ns | injection beam energy offset/% | RF frequency/MHz | RF voltage/kV | harmonic number | bunch spacing/ns | −5 | 4.34 | 100 | 350 | 160 | 10 |
|
Table 3. Main parameters of longitudinal injection scheme