This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 730871.
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Testing of Advanced RF Structures
TNA WP12 RF Test Stands
Roger Ruber (Uppsala University)
Walter Wuensch (CERN)
3rd Annual Meeting, 22 April 2020
WP12 RF Testing Facilities
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting2
The TNA within WP12 groups TWO facilities devoted to testing of superconducting RF cavities and normal conducting RF cavities.
HNOSSUppsala
University
XBOXCERN
Geneva
TASK 12.1 HNOSS
TASK 12.2 XBOX
WP12.1 UU/FREIA HNOSS Facility
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting3
The HNOSS facility at the FREIA Laboratory, Uppsala University, Sweden, is available for testing of superconducting RF cavities with integrated helium tank.
HNOSSUppsala
University
TASK 12.1 HNOSS
WP12.1 UU/FREIA HNOSS - Overview
In proposal - 4 projects with a total of 2880 access units.
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting4
Name Institutes Status Access units Users
ESS High-beta Elliptical Cavity CEA Saclay Completed.
Reported and published.
1330 18
Validation of a prototype
double spoke cavity
cryomodule
IPN Orsay Completed.
Reporting ongoing.
2048 14
RF and piezo actuators
study on spoke cavities
Lodz University
of Technology
Completed.
Reported and published.
36 8
HL-LHC crab cavity cold
testing
CERN Approved end February (480) (7)
TOTAL Achieved Today 3414 (118%) 40
WP12.1 FREIA-HNOSS-2018-01
• Validation of prototype double spoke cavity
cryomodule
• validation valve box in Dec. 2018 & Jan. 2019
• thermo-acoustic (Taconis) oscillations
→ installed RLC circuit
• cryomodule quench → rupture disk replaced
• Results
• RF conditioning → several multipacting bands
• revealed problems in RF stations and LLRF synchronization → fixed!
• stable operation at 2K
• measured accelerating gradient, heat load
→ better than target requirements
• studied Lorenz force detuning,
frequency sensitivity vs. temp., pressure
• Full Report in preparation
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting5
WP12.1 FREIA-HNOSS-2019-01
• RF and piezo actuators study on spoke cavities
• use cavities from cryomodule project HNOSS-2018-01
• Results
• measurement of piezo & cavity operational parameters,
• verified and modified specifications for spoke cavities
resonance control system
• design verification of control system and algorithms.
• main parameters of designed driver has to be modified
• triggered discussion to harmonize piezo driver
system for ESS spoke and elliptical cavities
• Report
• LLRF 2019 poster
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting6
WP12.2 CERN XBox Facility
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting7
The XBox facility at CERN, Switzerland, is available for testing ofnormal conducting RF cavities/structures at X-band frequency.
XBOXCERN
Geneva
TASK 12.2 XBOX
WP12.2 CERN XBox - Overview
In proposal - 4 projects with a total of 6000 access units.
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting8
Name Institutes Status Access units Users
Dark current and breakdown
Spectrometer
Uppsala
University
Completed.
Reported and published
1680 6
X-band pulse compression
chain
PSI and
Tsinghua
University
Underway.
First publication, PRAB.
2500 and
continues
7
X-band RF deflecting
structure testing
Lancaster
University and
SARI (Shanghai)
Preparation.
SARI structure ready for
installation, Lancaster
structure under assembly
(3000) (6)
Measurement of the
Average Power limitation for
High Gradient X-band
Accelerating Structures for
Future Light Sources
Technical
University of
Eindhoven
Approved end February (500) (5)
TOTAL Achieved Today 4180 (70%) 13
WP12.2 CERN-XBOX-2018-01
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting9
Project 2:X-band pulse compression chain
Corrector cavity chain Barrel Open Cavity Pulse Compressor
Under testing in Xbox-2, 2500 h and continuesFirst publication, PRAB.
WP12.2 CERN-XBOX-2018-01
• Validation of the high power performance
of a new pulse compressor cavity (BOC)
and correction cavity chain (CCC)
for X-band operation
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting10
klystron output
BOC output
correction cavity output
WP12.2 CERN-XBOX-2019-01
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting11
Project 3X-band RF deflecting structure testing
SARI (Shanghai) deflector cavity arrived at CERN;ready for installation
Lancaster deflector (crab) cavityunder assembly
WP12 TNA - Outlook
• A typical User Project is quite complex, often requires some form of
approval at the level of the proposing institutes, so lead times are long.
• Assuming an autumn restart, we expect that
WP12 will fulfill project and access unit requirements
by the original ARIES end date.
• If a further year is granted, Xbox projects 2, 3, and 4 will continue.
• This will increase the access units, and ease risk on delay of one of the two
structures of project 3.
WP12 Testing of Advanced RF Structures - Roger Ruber - 22-April-2020 - 3rd ARIES annual meeting12