Characteristics of Beam Modes at the ESRF
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Beam mode & characteristics
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Intensity
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Lifetime
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Beam
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Uniform filling mode
992 bunches are equally distributed around the whole circumference of the storage ring.
Refill frequency: every hour
|
200 mA
|
25 hours
|
Low emittance
εh = 130 pm.rad
ε√ = 10 pm.rad
|
| 7/8 + 1 filling mode
A train of 868 bunches (7/8 of the Storage Ring circumference) filled with 192 mA (0.23 mA / bunch).
The remaining 1/8 gap is filled in its center with a cleaned 8 mA-single bunch
Refill frequency: every hour |
200 mA
|
24 hours
|
Low emittance
εh = 130 pm.rad
ε√ = 20 pm.rad
|
Hybrid mode 28*12 + 1 filling mode
One clean 8mA single bunch diametrically opposed to a ~ 192 mA multi-bunch beam composed of 28 groups of bunches spread over 3/4 of the storage ring circumference.
Refill frequency: every hour |
200 mA
|
5 hours (single bunch) -> resulting lifetime ~ 17 hours |
Low emittance
εh = 130 pm.rad
ε√ = 20 pm.rad
|
16 bunch filling mode
16 highly populated and equally spaced bunches. Purity < 10-7
Refill frequency: every hour |
75 mA
|
5.5 hours
|
Low emittance
εh = 135 pm.rad
ε√ = 20 pm.rad
|
4 bunch filling mode
4 highly populated and equally spaced bunches. 10 mA/bunch
Refill frequency: every hour |
40 mA |
5 hours |
Low emittance
εh = 135 pm.rad
ε√ = 20 pm.rad
|
MDT (Machine Dedicated time)
Operation for machine physics |
Depending on programme
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Depending on programme
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Depending on programme |
Shutdown
Shutdown period of the machine for maintenance, repairs, installation etc. |
No beam |
No beam
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No beam |
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