SLS Storage Ring Optics

F4T


Comment

Based on D2R55 this optics including the FEMTO triplet was developed: The additional focussing is such, that the vertical tune was increased by 0.5 and the horizontal tune kept constant, in order to not disturb the sextupole pattern ("pi-trick"). So only the 7 quads of the femto-straight (triplet plus adjacent two ring quads on both sides) were changed and no sextupoles but SF,SD to compensate the slight increase in chromaticity. Note, that the ring quad QLH-05 was changed by a longer type and also shifted. This optics is in operation since April 2004.

Optics F4TJB2 has an alternative sextupole setting, kindly optimized by Johan Bengtsson at BNL: it provides better injection efficiency, but has shorter lifetime. Sometimes it was used in a "swap mode" for fast refill after beam loss.

Data

Circumference [m] 288.000
Working Point Qx / Qy 20.41 / 8.67
Natural chromaticities -66.9 / -22.7
Corrected chromaticities +5 / +5
Momentum compaction factor 6.58E-4
Horizontal emittance at 2.4 GeV [nm rad] 4.93
rms relative energy spread at 2.4 GeV 8.58E-4
Energy loss per turn (no IDs) [keV] 519 (incl. Femto U19)
Short straight: Beta_x / Beta_y / Disp [m] 1.38 / 0.87 / 0.00
Medium straight: Beta_x / Beta_y / Disp [m] 2.35 / 2.70 / 0.00
Long straight: Beta_x / Beta_y / Disp [m] 4.58 / 3.64 / 0.00
FEMTO radiator: Beta_x / Beta_y / Disp [m] 9.33 / 0.42 / 0.00 (alfa_x = -2)
Maximum values: Beta_x / Beta_y / Disp [m] 23.1 / 23.7 / 0.35

Additional Material

F4T Lattice file for OPA

F4TJB2 Lattice file for OPA

F4T snap file for upload to control system

F4TJB2 snap file for upload to control system

F4T Lattice file composed from database as input for TRACY

F4T listing of beta functions (TRACY)