Title: LCLS quadrupoles after upgrade 123 laminations
1LCLS quadrupoles after upgrade (123 laminations)
2Center motion from Hall probe datadue to
quadrupole change
Scan of Bx(T) vs Y(mm). Done for quad currents
I-6A, 6A, 4.5A20 Center motion is less than 2
µm. Quad1 data are very close to shown here
3Center motion from Hall probe datadue to
correctors (article1)
Scan of Bx(T) vs Y(mm). Done for I(Q)4.5A
Corrector current was changed from 0.5 A to
0. Center motion is close to 1 µm.
4No quadrupole saturation
5Hall probe scan Bx vs. Z
Red Y2.5 mm, Blue Y-2.5 mm
6Hall probe scan
Integrated gradient calculated from slide 4 is
3.13 T _at_ I4.5 A and 4.17 T 0.2 _at_ I6 A
7Hall probe scan By vs. Z
Gradient G(z)B(x2.5mm)-B(x-2.5mm)/2x Integr
ated gradient for 1mmltZlt130mm is 4.136 T1 _at_ I6A
8Correctors _at_ I0.5A
9Correctors _at_ 0.5A
Close to article 2 JxgtJy by 15
10Summary
- Strength of quadrupole at 4.5A is 3.13 T
- at 6A is 4.17 T
- integrated over
129 mm - Data shown correspond to Hall probe measurements
of horizontal field dependence on Y. Due to
specifics of magnetic measurement system
(encoders resolution) scan in Y is preferable. - All data agree very well with previous
measurements. The difference is change in field
integrals, which is proportional to the number of
laminations. - Accuracy of integrated gradient depends on
knowledge of distance between two scans
(5mm0.01mm) and alignment of Hall probe and
could be estima - ted as 0.5
11Integrated gradient vs. quad cycles