Meeting summary (so far, Monday morning) and comments

Meeting summary (so far, Monday morning) and comments

Tom Peterson, Camille Ginsburg (FNAL), Alex Ratti (LBNL)Crab Cavity Meeting, CERN, 1-6 Aug 2013

LHC Crab Cavities, 5 Aug 20132

CERN services and capabilities – visits

• Main workshop and metrology (building 100) – Said Atieh

• Surface treatment infrastructure (building 118) and sputtering infrastructure (building 252) – Sergio Calatroni

• Metallurgy and non-destructive testing (building 599) – Gonzalo Arnau Izquierdo, Ignacio Aviles Santillana

• Vacuum brazing and new E-beam welding machine (building 112) – Said Atieh

• Cryo-bypass for LHC collimators (building 112) –Said Atieh, Thierry Renaglia


CERN services and capabilities – more

• SM18 (RF test caves, vertical dewars, magnet test facility) – Mathieu Therasse, Torsten Koettig

• Mechanical measurements lab (building 376) – Michael Guinchard (CERN)

• SMI2 (magnet assembly and staging area, SPL cavity support structure mock-up) – Arnaud Vande Craen, Rossana Bonomi, Michael Guinchard

• In summary: truly remarkable fabrication and measurement capabilities, most impressive, and very knowledgeable personnel


SM18

• Cleanroom areas • Cryomodule assembly areas • Vertical dewar test cryostats • Test caves with cryogenics capable of hosting a

full cryostat test including the service module prior to installation into SPS


SPL cryomodule – Rossana Bonomi, Arnaud Vande Craen

• Several novel features are being studied • Support via a double-walled tube through which

is placed the input coupler Input coupler then precisely at the cavity fixed-point

• Other cavity end supported by bridge to the next cavity

• Round vacuum vessel but opens via top lid, long O-ring seal


Alignment systems – optical (HEI-ISOLDE)


Alignment systems – stretched wire (SPL)


CERN Cryomodule Requirements for Crab Cavities – O. Capatina (CERN)

• This talk by Ofelia provides a good overview of the constraints and requirements

• Key document is still the Functional Specification


Crab Cavity Interfaces


Various key constraints have been identified


SPS cryogenics – Krzysztof Brodzinski


Discussion, possible modifications

• Supply bypass (4.5 K) around heat exchanger • Cool-down return via heat exchanger and

pumping line (up to cool-down branch) • Optional 4.5 K supply to manifold below

cryostats for warm-up and cool-down, to be determined based on operational requirements


Crab Cavity Compliance Requirements


ASME options

• ASME pressure vessel code, Section VIII for pressure vessels, has two major divisions

Section VIII, Div 1 is design by rules, most formulas provided although there is some freedom where none apply

Section VIII, Div 2, is design by analysis


Fermilab’s SRF pressure vessel standard


Safety compliance conclusion

• As a top priority in this project, we will work closely with CERN’s EN/MME Design Office Team to satisfy CERN safety requirements

• In detailed follow-up discussions on this topic, we can provide more information about our standards (ASME and our SRF cavity vessel standard), as those may also help to reach a detailed understanding of requirements here


Cryomodule for UK 4Rod cavity – Thomas Jones, Shrikant Pattalwar (STFC Daresbury Laboratory, UK)

• Nice conceptual design of dressed cavity and cryomodule including structure


Present direction for cryostat work

• With three cavity options Daresbury continues their design for their cavity US effort looks at common elements for our two cavities,

also taking as much as possible from CERN and Daresbury cryostat design work

• Funding to continue with all three cavities may not be available. If one US cavity is selected for inclusion in a cryostat, US will focus on that design

• If Daresbury cavity is not continued, we will focus on one US cavity while Daresbury works with the other

• US support is, unfortunately, still rather uncertain Hope to have a designer this fall who will assist with CAD

modeling details


Cryomodule assembly

• CERN is certainly capable of doing full cryomodule assembly

• So is Fermilab • Let’s see what support Fermilab receives over

the next 4 months and prospects for funding beyond that to assess whether assembly at Fermilab remains an option


Conclusions (as of Monday morning!)

• Excellent meeting, well organized, very informative • This collaboration definitely has the expertise and

infrastructure to accomplish the task of building a crab cavity cryomodule for tests in SPS

Although we all recognize that the funding is uncertain and the schedule for installation into SPS is very ambitious

Close coordination for best use of our resources will be very important

• Among our next tasks should be to define the dressed cavity safety compliance requirements, since those may move to advanced design stages soon

Niowave will focus on dressed cavity design and construction initially for their SBIR

We need to ensure that those first dressed cavities satisfy all requirements including documentation

Meeting summary (so far, Monday morning) and comments

Documents

Transcript of Meeting summary (so far, Monday morning) and comments