SRF2013 - List of Authors (Gandolfo, N.)

Paper

Title

Page

Spiral2 Cryomodules B Tests Results

95

G. Olry, F. Chatelet, C. Commeaux, N. Gandolfo, D. Grolet, C. Joly, J. Lesrel, D. Longuevergne, R. Martret, G. Michel, L. Renard, A. Stephen, P. Szott
IPN, Orsay, France
P.-E. Bernaudin, R. Beunard, R. Ferdinand, A. Lefevre
GANIL, Caen, France
Y. Gómez Martínez
LPSC, Grenoble Cedex, France

Assembly and tests of the SPIRAL2 superconducting linac's cryomodules at CEA/Saclay and IPN/Orsay have now reached cruising speed after having faced a series of problems, among them contamination. 19 cryomodules are composing the whole Linac and IPN Orsay is in charge of the 7 cryomodules B, housing two 88MHz, beta 0.12 Quarter-Wave Resonators. Two cryomodules have been successfully assembled and tested up to the nominal gradient of 6.5 MV/m for all cavities with also total cryogenic losses under specifications. One of them is fully qualified and has been already delivered to GANIL. The second one showed misalignment on one cavity which could lead to partial disassembly. This paper will present the results of those cryomodules tests as well as the status of the remaining ones.

MOP075

A X-rays Shielded Facility Dedicated to Cryogenic RF Tests of Fully Dressed Spoke Cavities in the Cryomodule CM0 at IPN Orsay

M. Fouaidy, P. Duchesne, N. Gandolfo, D. Grolet, C. Joly, G. Olry, M. Pierens, V. Poux, D. Reynet
IPN, Orsay, France
C.C. Motta
USP, São Paulo, Brazil

A bulk Nb superconducting β=0.3 Triple-Spoke (T-Spoke) cavity operating at 352 MHz, was designed at IPN and fabricated thanks to EURISOL project financial support. The cavity will be tested in November 2013 at a new X-rays shielded facility dedicated to cryogenic tests of fully dressed (LHe tank, Magnetic Shields, Fast Active Cold Piezoelectric Tuning System (FACPTS), RF Power coupler) Spoke cavities in the horizontal cryomodule CM0. The CW RF power and cryogenic power @T=2K are 80kW and 120W respectively. Four vertical cold RF tests were performed in a vertical cryostat and the data are reported. All components (cold box, cryogenic lines, He gas heater, RF power system with 2 RF power couplers, LHe bath pumps) were delivered and successfully tested. The cryogenic circuit in CM0 was finished and we successfully mounted the fully dressed T-Spoke cavity. A R.T tuning system was used for static and dynamic mechanical measurements on Single (S-Spoke) and T-Spoke cavities. Mechanical stiffness, transfer function, vibrations, Lorentz detuning were investigated using the FACPTS. Field profile in S-Spoke and T-Spoke cavities were performed using a motorized field perturbation stand.

MOP089

Design of the ESS Spoke Cryomodule

357

D. Reynet, S. Bousson, S. Brault, P. Duchesne, P. Duthil, N. Gandolfo, G. Olry, E. Rampnoux
IPN, Orsay, France

The European Spallation Source (ESS) project brings together 17 European countries to develop the world’s most powerful neutron source feeding multidisplinary researches. The superconducting part of the linear accelerator consists in 59 cryomodules housing different superconducting radiofrequency (SRF) resonators among which 28 paired β=0.5 352.2 MHz SRF niobium double Spoke cavities, held at 2K in a saturated helium bath. A prototype Spoke cryomodule with two cavities equipped with their 300kW RF power couplers is now being designed and will be constructed and tested at full power by the end of 2015 for the validation of all chosen technical solutions. It integrates all the interfaces necessary to be operational within a linac machine. Its assembly requires dedicated tooling and procedures in and out of a clean room. The design takes into account an industrial approach for the management of the fabrication costs. This prototype will have to guarantee an accelerating field of 8MV/m while optimizing the energy consumption and will aim at assessing the maintenance operations issues. We propose to present the design of this cryomodule and its related tooling.

THIOD04

A Cold Tuner System With Mobile Plunger

884

D. Longuevergne, S. Blivet, S. Bousson, N. Gandolfo, G. Martinet, G. Olry, H. Saugnac
IPN, Orsay, France

Tuner systems for accelerating cavities are required to compensate static and dynamic frequency perturbations during beam operation. In the case of superconducting cavities, these are commonly tuned by deforming the cavity wall in specific places of the geometry. Nevertheless, considering the mechanical properties and frequency versus displacement sensitivity of some structures, tuning by deformation doesn’t allow to meet the requirements. In these specific cases, inspired from the “room temperature technology”, an alternative tuning technique by insertion of a helium-cooled superconducting plunger can be considered and has been studied for several projects (IFMIF, ESS-BILBAO). Advantages and drawbacks of such solution will be discussed and the successful results on SPIRAL2 cryomodule developed at IPNO will be presented.

Slides THIOD04 [4.938 MB]

THP078

Deformation Tuner Design for a Double Spoke Cavity

1104

N. Gandolfo, S. Bousson, S. Brault, P. Duchesne, P. Duthil, G. Olry, D. Reynet
IPN, Orsay, France

IPN Orsay is developing the low-beta double Spoke cavities cryomodule for the ESS. Based on previous successfully tested prototypes, a fast/slow tuner has been studied to compensate resonance frequency variations of the cavity during operation. The typical perturbations are coming from LHe pressure variations as well as microphonics and Lorentz force detuning (LFD). Two tuners are being built in order to validate both expected performances and series production feasibility. In this paper, the tuner design of the double Spoke cavity is presented.

Paper	Title	Page
MOP010	Spiral2 Cryomodules B Tests Results	95
	G. Olry, F. Chatelet, C. Commeaux, N. Gandolfo, D. Grolet, C. Joly, J. Lesrel, D. Longuevergne, R. Martret, G. Michel, L. Renard, A. Stephen, P. Szott IPN, Orsay, France P.-E. Bernaudin, R. Beunard, R. Ferdinand, A. Lefevre GANIL, Caen, France Y. Gómez Martínez LPSC, Grenoble Cedex, France
	Assembly and tests of the SPIRAL2 superconducting linac's cryomodules at CEA/Saclay and IPN/Orsay have now reached cruising speed after having faced a series of problems, among them contamination. 19 cryomodules are composing the whole Linac and IPN Orsay is in charge of the 7 cryomodules B, housing two 88MHz, beta 0.12 Quarter-Wave Resonators. Two cryomodules have been successfully assembled and tested up to the nominal gradient of 6.5 MV/m for all cavities with also total cryogenic losses under specifications. One of them is fully qualified and has been already delivered to GANIL. The second one showed misalignment on one cavity which could lead to partial disassembly. This paper will present the results of those cryomodules tests as well as the status of the remaining ones.

MOP075	A X-rays Shielded Facility Dedicated to Cryogenic RF Tests of Fully Dressed Spoke Cavities in the Cryomodule CM0 at IPN Orsay
	M. Fouaidy, P. Duchesne, N. Gandolfo, D. Grolet, C. Joly, G. Olry, M. Pierens, V. Poux, D. Reynet IPN, Orsay, France C.C. Motta USP, São Paulo, Brazil
	A bulk Nb superconducting β=0.3 Triple-Spoke (T-Spoke) cavity operating at 352 MHz, was designed at IPN and fabricated thanks to EURISOL project financial support. The cavity will be tested in November 2013 at a new X-rays shielded facility dedicated to cryogenic tests of fully dressed (LHe tank, Magnetic Shields, Fast Active Cold Piezoelectric Tuning System (FACPTS), RF Power coupler) Spoke cavities in the horizontal cryomodule CM0. The CW RF power and cryogenic power @T=2K are 80kW and 120W respectively. Four vertical cold RF tests were performed in a vertical cryostat and the data are reported. All components (cold box, cryogenic lines, He gas heater, RF power system with 2 RF power couplers, LHe bath pumps) were delivered and successfully tested. The cryogenic circuit in CM0 was finished and we successfully mounted the fully dressed T-Spoke cavity. A R.T tuning system was used for static and dynamic mechanical measurements on Single (S-Spoke) and T-Spoke cavities. Mechanical stiffness, transfer function, vibrations, Lorentz detuning were investigated using the FACPTS. Field profile in S-Spoke and T-Spoke cavities were performed using a motorized field perturbation stand.

MOP089	Design of the ESS Spoke Cryomodule	357
	D. Reynet, S. Bousson, S. Brault, P. Duchesne, P. Duthil, N. Gandolfo, G. Olry, E. Rampnoux IPN, Orsay, France
	The European Spallation Source (ESS) project brings together 17 European countries to develop the world’s most powerful neutron source feeding multidisplinary researches. The superconducting part of the linear accelerator consists in 59 cryomodules housing different superconducting radiofrequency (SRF) resonators among which 28 paired β=0.5 352.2 MHz SRF niobium double Spoke cavities, held at 2K in a saturated helium bath. A prototype Spoke cryomodule with two cavities equipped with their 300kW RF power couplers is now being designed and will be constructed and tested at full power by the end of 2015 for the validation of all chosen technical solutions. It integrates all the interfaces necessary to be operational within a linac machine. Its assembly requires dedicated tooling and procedures in and out of a clean room. The design takes into account an industrial approach for the management of the fabrication costs. This prototype will have to guarantee an accelerating field of 8MV/m while optimizing the energy consumption and will aim at assessing the maintenance operations issues. We propose to present the design of this cryomodule and its related tooling.

THIOD04	A Cold Tuner System With Mobile Plunger	884
	D. Longuevergne, S. Blivet, S. Bousson, N. Gandolfo, G. Martinet, G. Olry, H. Saugnac IPN, Orsay, France
	Tuner systems for accelerating cavities are required to compensate static and dynamic frequency perturbations during beam operation. In the case of superconducting cavities, these are commonly tuned by deforming the cavity wall in specific places of the geometry. Nevertheless, considering the mechanical properties and frequency versus displacement sensitivity of some structures, tuning by deformation doesn’t allow to meet the requirements. In these specific cases, inspired from the “room temperature technology”, an alternative tuning technique by insertion of a helium-cooled superconducting plunger can be considered and has been studied for several projects (IFMIF, ESS-BILBAO). Advantages and drawbacks of such solution will be discussed and the successful results on SPIRAL2 cryomodule developed at IPNO will be presented.
	Slides THIOD04 [4.938 MB]

THP078	Deformation Tuner Design for a Double Spoke Cavity	1104
	N. Gandolfo, S. Bousson, S. Brault, P. Duchesne, P. Duthil, G. Olry, D. Reynet IPN, Orsay, France
	IPN Orsay is developing the low-beta double Spoke cavities cryomodule for the ESS. Based on previous successfully tested prototypes, a fast/slow tuner has been studied to compensate resonance frequency variations of the cavity during operation. The typical perturbations are coming from LHe pressure variations as well as microphonics and Lorentz force detuning (LFD). Two tuners are being built in order to validate both expected performances and series production feasibility. In this paper, the tuner design of the double Spoke cavity is presented.