HOM coupler size Hongjuan Zheng Damping Scheme for

HOM coupler size Hongjuan Zheng

Damping Scheme for Crab Waist Design When HOM power and high frequency modes behavior are determined, we could choose the damper. n In the crab waist case, the maximum HOM damping is 0. 9 k. W per cavity. In ideal case, 80 % above cut-off frequency of the 156 mm beam pipe. n Coaxial: notch filter BW and tuning, cooling, feedthrough antenna heating, RF connection heating, cable heating …LEP/LHC-type, LHC-HL, BNL ERL& e. RHIC HOM coupler for the k. W level power capacity. n KEKB and Super. KEKB ferrite HOM absorbers 20 k. W at RT. LEPII: 850 W /coupler (CW test) LHC narrowband broadband coupler: design value— 1 k. W, test— 600 W (4. 5 K) HL-LHC 400 MHz crab & DQW cavity: design value— 1 k. W HL-LHC 2 nd harmonic cavity(800 MHz): 2 hook +2 probe/cavity. 525 W/ hook & 61 W/probe

LEPII Φ=286. 4 mm Φ=200 mm Φ=100 mm Beam tube penetration: H=286. 4/2 -(240 -139)m =42. 2 mm Φ=16 mm Φ=103± 0. 1 mm h=96. 8 mm h=139 mm

LHC Beam tube: Φ=300 mm Φ=103 mm h=317 mm h≈118 mm Φ=16 mm Beam tube penetration: H=42. 2 mm (same with LEP) h=234 mm h≈89 mm

HOM coupler design for High current SRF cavities (Wencan XU )

IHEP-02 1. 3 GHz low loss Beam tube: Φ=80 mm Φ=40 mm Main coupler: Φ=60 mm