Operating Modes
last modified
27-01-2012 11:29
Characteristics of Beam Modes at the ESRF
Animations
illustrate the filling modes currently used at the ESRF (flash
plug-in required)
|
Beam
mode & characteristics
|
Intensity
|
Lifetime
|
Beam
|
Uniform
filling mode
992 bunches are equally distributed around the whole
circumference of the storage ring.
Refill time: ~3 minutes
|
200
mA
|
60
hours
|
Low
emittance
(4 nm) with 1% coupling |
2*1/3 filling mode
2 times one third of the storage ring is filled. The 2 one thirds are separated by an empty gap of 1/6th of the ring.
Top up time: ~3 minutes
|
200 mA
|
55 hours
|
Low
emittance
(4 nm) with 1 % coupling. |
|
7/8 + 1
filling mode
A
train of 868 bunches (7/8 of the Storage Ring circumference) filled with 200 mA
(0.23 mA / bunch).
Both
edges of the train are filled with 1 mA single bunch
The remaining 1/8 gap
is filled in its center with a cleaned 2 mA-single bunch
Filling time: ~ 5 minutes |
200 mA
|
55 hours
|
Low
emittance
(4 nm) with 1% coupling.
|
Hybrid mode 24*8 + 1 filling mode
One clean 4mA single bunch
diametrically opposed to a ~ 196 mA multi-bunch beam composed of 24 groups of
bunches spread over 3/4 of the storage ring circumference.
Filling time: ~ 10 minutes. |
200
mA
|
25 hours (single bunch)
40 hours (24*8 bunches)
-> resulting lifetime ~ 40 hours |
Low
emittance
(4 nm) with 1 % coupling. |
16
bunch filling mode
16
highly populated and equally spaced bunches. Purity
< 10-7
Filling
time: ~5 mins. |
90 mA
|
10 hours
|
Low
emittance
(4 nm) with 2% coupling |
4*10 filling mode
4 equidistant bunches _ 10 mA/bunch
Filling time: ~ 5 minutes |
40
mA |
6 hours |
Low
emittance
(4 nm) with 2% coupling. |
MDT
(Machine Dedicated time)
Operation
for machine physics |
Depending
on programme
|
Depending
on programme
|
Depending
on programme |
Shutdown
Shutdown
period of the machine for maintenance, repairs, installation
etc. |
No
beam |
No
beam
|
No
beam |
|
