1. LHC Crab Cryostat Integration and Planning Meeting – some outcomes
O. Capatina
OC, 5/June/2013
CCTC

2. General
LHC Crab Cryostat Integration and Planning Meeting in Fermilab on 30-31/05/2013
Objectives:
- define/understand the scope of the SBIR
- a plan to integrate the current designs into a final design for the SPS test into a cryostat
- an overall schedule on how to get to the SPS test
- (on Friday for the LARP group) a revised budget to get there, possibly identifying which contributions we can include from outside LARP (UK. CERN, GARD, SBIRs...).
OC, 5/June/2013
CCTC

3. Talks Specification : some outcomes
Request for CM integration study to check feasibility with reduce space for SPS (225 mm) to avoid new Y chamber
Clarification request for coupler vertical / horizonta: specification or wish?
LHC adjacent pipe dimension to be checked and check compliance with geometrical specification of cavities
Remark: SPS test very tight in schedule: for CM requirements try to keep only the very important points that will be needed for the LHC and not for SPS: => Alignment a very important point for CM to be clarified with high priority
Where the cryostating will be done – to be defined – will have impact on Technical design of the cryomodule
Specification document to be updated soon clarifying the points for SPS and LCH separately
OC, 5/June/2013
CCTC

4. General
December 2012 meeting concluded with some basic choices for SPS tests:
2 (identical) cavities in a cryomodule
3 different cryomodules
Our “wishful path” is to have conceptual designs of the 3 cryomodules by Dec 2013
T. Peterson to coordinate the effort
The UK team are in a slightly advanced stage
OC, 5/June/2013
CCTC

5. Talks Cavities developments Only US cavities presented
Both are redesigned to meet geometrical specifications issued after the meeting in last December
ODU cavity
POP cavity tested – good results
Cavity redesign/ LHC close to finished; helium tank and tuner only at the concept phase;
BNL cavity
POP cavity expected to be tested starting last Monday
Cavity redesign /LHC, helium tank and tuner advancing together as an integrated design
Coupling ports, HOM couplers under optimisation
OC, 5/June/2013
CCTC

6. Talks
ODU
OC, 5/June/2013
CCTC

7. Summary Proof-of-Principle cavity achieved 7 MV deflecting voltage cw
Residual surface resistance a little high (34 nΩ)
Consistent with losses in stainless steel flanges
Multipacting quickly processed and did not reoccur
Proof-of-Principle cavity has achieved its purpose
Ready to move on to the prototype cavity
Reasonably confident that 10 MV can be achieved with 2 cavities

8. Prototype Design vs. Proof-of-Principle
ODU/SLAC
Cavity Design Evolution
Prototype Design
Cavity Dimensions
Prototype
Design
Proof-of-
Principle
Units
Radius
140.5
170 mm
Iris-to-iris Length
535
528
Beampipe
aperture 42

9. Mechanical Analysis Pressure Sensitivity -30 Hz/torr
Tuning Sensitivity +90 kHz/mm
Lorentz Force Detuning -20 Hz/(MV/m)2
All characteristics improved from the proof of principle cavity design
Lorentz force detuning Deformation scale 5.8e+4
Niobium property at 2-4K
Picture not showing adjacent beam pipe but included in the analysis

10. Helium tank/Tuner Assembly
Cryostat Concept
Helium tank/Tuner Assembly
Horizontal beam deflection
Vertical beam deflection
Ongoing brain-storming to use identical helium tank for both configuration if it is beneficial

11. Talks
BNL
OC, 5/June/2013
CCTC

12. Crabbing (fundamental) mode freq.
DQWCC POP version
390
337
296
362
295
unit: mm
Crabbing (fundamental) mode freq.
1st HOM
Cavity length
Cavity width
Beam pipe diameter
Deflecting voltage
Unit
MHz mm MV
DQW crab cavity
400
579
390
148 84
3.3
5/30/13

13. POP version in LHC
Cavity length along beam pipe (with 4 mm wall thickness included):
390 mm
Cavity width perpendicular to beam pipe (with 4 mm wall thickness included):
295 mm
Gap between cavity outer surface and nearby beam pipe outer surface:
1.24 mm
# of ports total: 6
# of HOM couplers: 4
Inner diameter of all coupler ports: 28 mm
Fabrication of prototype cavity is underway.
Cavity is made out of only sheet material
4/9/13

14. Tuner - Design © B. Xiao @ CC workshop 2012
Thermal leak from one drive shaft and piezoelectric wires.
Threaded rod (or differential screw) provides coarse tune.
Piezoelectric in series with threaded rod provides fine tune.
Step motor (RT) is attached to the cryomodule with a Conflat flange. The single rod linkage into the cryostat limits the thermal load.
Effectively use the space: give more space to couplers make the magnetic shielding easier
12/13/12

15. Talks Niowave Grant for crab project activities
Capabilities and company interest discussed
OC, 5/June/2013
CCTC

16. SBIR Phase II DOE-HEP Phase II SBIR Schedule
1 million dollars over 2 years
Schedule
Contract Start April 2013
Year 1 progress report due Feb 2014
Year 2 final report due March 2015
Start transition to Phase III in late 2014

17. Talks LARP Plans Scope of US contribution
Mentioned some conclusions of the discussions
OC, 5/June/2013
CCTC

18. Scope of US Contribution
LARP funds R&D until the SPS test
Deliver one cryomodule for testing in the SPS in ~ and possibly in Pt-4 in the LHC
2 cavities, He vessels, tuners, HOM mode dampers
RF couplers provided by CERN
Cryogenics, RF power, local installation provided by CERN
US Construction project funds production
Deliver 10 cryomodules of 3 cavities each
Contain cavities, He vessels, tuners, HOM mode dampers
8 CM needed in pts 1 and 5, 2 spares (one per IP)

19. US Construction Project
Crab cavities are included among the tasks selected in December 2012 as part of the construction project in support of the HL-LHC
Feedback from DOE reminds that the effort on crab cavities should be carried through construction
Should not limit this contribution to the SPS test

20. Today’s Results
The SBIR cryostat is going to be designed to be capable of going to the SPS test
Will house two cavities
The Cryostat for the SPS test will NOT be the one for the final installation in the LHC.
It *may* be compatible with a test in IP4, but this should not come at a big cost in time and money
We’re only planning a test with a kick in one plane
Will have two cavities
The current plan for the SPS is to run until the end of 2017
We will still try to hold the delivery to CERN by the end of 2015
We don’t need external approval for the pressure vessel
But need all traceable documentation
We need a more precise plan on who is doing the cryostat mechanical integration and H testing

21. More Results
Should plan for an intermediate step of the dressed prototype cavities in a Vertical Test
ANL may be a good place to test
We carry both design to a dressed cavity test

22. Discussions Planning SPS LHC Resources US UK CERN:
We will perform engineering verifications for all cavities/helium tank/tuner designs
We have committed for manpower effort (identified design and analysis for the moment) to be added to the cryomodule development US and UK effort
OC, 5/June/2013
CCTC

23. SPS Planning
OC, 5/June/2013
CCTC

24. LHC Planning
OC, 5/June/2013
CCTC

25. AOB Tom Peterson visit at CERN Date still to be defined
Target ~ 1 week
Include discussions related to pressure equipment aspects (safety)
OC, 5/June/2013
CCTC