Xband pulse compressors at Tsinghua Yuliang Jiang CLIC
X-band pulse compressors at Tsinghua Yuliang Jiang CLIC Workshop, 21 -25 January 2019
Outline Ø Backgrounds Ø Correction cavity chain for CLIC Ø X-band pulse compressor for TTX Ø Summary
Backgrounds Klystron-based CLIC X-band High power test facility at Tsinghua
Outline Ø Backgrounds Ø Correction cavity chain for CLIC Ø X-band pulse compressor for TTX Ø Summary
Correction cavity chain for CLIC u Design of correction cavity chain for CLIC [1] Ping Wang, Hao Zha, Igor Syratchev, Jiaru Shi, and Huaibi Chen, rf design of a pulse compressor with correction cavity chain for klystron-based compact linear collider , Phys. Rev. Accel. Beams 20, 112001 (2017)
Correction cavity chain for CLIC u Cold measure of CC before brazing Ø Before brazing, the unloaded quality factors were less than the designed ones. Ø The torque was 1 N·m.
Correction cavity chain for CLIC u Preliminary tuning of CC before brazing Ø The frequencies of four directions were tuned by cutting off a little bit of the resonant cavities. Ø Working temperature of CC is 30 ℃. D 1 D 2 D 3 D 4
Correction cavity chain for CLIC u Three cavities were melted while brazing Ø The three cavities were re-fabricated. Ø The frequency shift after the preliminary tuning were not measured this time. melted
Correction cavity chain for CLIC u Previous measure method after preliminary tuning Ø Each set consisted of a brazed cavity and an unbrazed cavity. Ø The cut-off thickness at the mid-plane of the cavity was ~0. 02 mm. Ø Under this condition, the unbrazed cavity wasn’t compressed tightly as the pressure was almost remained in the brazing surface of the brazed cavity. u Optimized measure method Ø Separate measurements Ø Applicable for cavities at the bottom.
Correction cavity chain for CLIC u The cavities were well brazed this time u Obvious frequency shifts were observed for two sets of cavities �� Simulated pulse shape after brazing Qstore=177, 000 β=5. 98
Correction cavity chain for CLIC u Tuning of the correction cavity chain Ø The frequency and the polarization of the cavity were tuned by tuning holes on it. Ø The frequency difference between two coupled cavities was tuned by holes in the middle. Tuning tools D 1 D 2 D 3 D 4
Correction cavity chain for CLIC u Results after tuning Ø Only the first two sets were tuned as tuning increased the reflection easily Ø The working temperature is set at ~ 32℃ Qstore=177, 000 β=5. 98
Outline Ø Backgrounds Ø Correction cavity chain for CLIC Ø X-band pulse compressor for TTX Ø Summary
X-band pulse compressor for TTX u X-band RF system for TTX Ø X-band Klystron: • 11424 MHz, • 50 MW, 1. 5 us Ø Pulse compressor: • Q 0=115, 000 • β = 3. 23 SLED-I RF load XC-72
X-band pulse compressor for TTX u Design of Corrugated Wall Cavity u Design of RF polarizer Port 2 Port 3(1) Port 3(2) Spherical Smooth cylindrical Corrugated cylindrical TE 01 mode TE 11 mode HE 11 mode Port 1
X-band pulse compressor for TTX u Measurements of RF polarizer and the corrugated cavity Reflection< -0. 12 d. B Result after preliminary tuning
X-band pulse compressor for TTX u Brazing and tuning Measured: Q 0=116, 750 β=3. 67
X-band pulse compressor for TTX u Low power test Ø Compress the RF pulse from 1. 5 us to 150 ns Ø Peak power gain more than 5
Outline Ø Backgrounds Ø Correction cavity chain for CLIC Ø X-band pulse compressor for TTX Ø Summary
Summary Ø The correction cavity chain was tuned and shipped to CERN. It has been installed on XBox 2 recently. High power tests will be conducted. Ø The pulse compressor based on corrugated wall cavity was low power tested, and the results match the simulation. It will be installed on the X-band high power test facility after the winter vacation.
Thanks for your attention ! CLIC Workshop, 21 -25 January 2019
- Slides: 21