Abstracts Brochure - CERN

MOPCH144
MOPCH145
MOPCH146
26-Jun-06 16:00 - 18:00 MOPCH — Poster Session
piezostacks. Experimental data are needed for reliable and optimum operation of piezostacks in superconducting
protons or electrons linacs. In the frame of the CARE project supported by EU, we designed and constructed a
dedicated apparatus for studying the electromechanical behavior of prototype piezoelectric actuators subjected to
variable preloading force at cryogenic temperatures. This device was successfully used for testing piezoelectric actuators
prototypes for T in the range 2K-300K. The dielectric properties as well as dynamic properties were measured
including the actuator characteristics when used as force sensor. The corresponding data are reported and discussed.
Low Temperature Properties of Piezoelectric Actuators Used in SRF Cavities Cold Tuning
Systems
G. Martinet, S. Blivet, F. Chatelet, M. Fouaidy, N. Hammoudi, A.
Olivier, H. Saugnac (IPN)
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High accelerating gradients (10 MV/m for
SNS, 33 MV/m for ILC) at which SRF cavities
will be operated in pulsed machines induce
frequency shift much higher than the
resonator bandwidth. This so-called Lorentz detuning should be compensated dynamically by means of an active
piezo-tuning system. In the frame of the CARE project activities supported by EU, IPN Orsay participates to the
development of a fast cold tuning system based and piezoelectric technology for SRF cavities operating at temperature
T=2K. The aim of this study is the full characterization of piezoelectric actuators at low temperature including
dielectric properties (capacitance, impedance, dielectric losses), radiation hardness tests (fast neutron tolerance), mechanical
measurements (maximum displacement, maximum stroke) and thermal properties (heating, heat capacity).
Results obtained in the temperature range from 2K up to 300K will be presented and discussed.
Tests Results of the Beta 0.07 and Beta 0.12 Quarter Wave Resonators for the SPIRAL2 Superconducting
Linac
G. Olry, J.-L. Biarrotte, S. Blivet, S. Bousson, C. Joly, T. Junquera,
J. Lesrel, H. Saugnac (IPN) P.-E. Bernaudin, P. Bosland, G. Devanz,
J.P. Poupeau (CEA) Y. Gómez-Martínez, F. Vezzu (LPSC)
New developments and tests have been
carried out on low beta (0.07) and high
beta (0.12) 88 MHz superconducting Quarter
Wave Resonators. These resonators will
be installed in the LINAC driver, respectively
in the low beta section, composed of cryomodules A (developed at CEA-Saclay) and the high beta section composed
of cryomodules B (developed at IPN-Orsay). Both resonators’ types will be equipped with the same power coupler
(developed at LPSC-Grenoble) and designed for a maximum power of 20 kW. RF tests results of the prototype cavities
and power couplers are reported. The fabrication of the two cryomodules prototypes, fully equipped, is in progress
in order to be ready for high power RF tests at 4.2 K at the beginning of 2007.
Status of the Beta 0.12 Superconducting Cryomodule Development for the Spiral2 Project
H. Saugnac, J.-L. Biarrotte, S. Blivet, S. Bousson, C. Joly, T. Junquera,
J. Lesrel, fl. Lutton, G. Martinet, G. Olry, P. Szott (IPN)
SPIRAL2 is a radioactive beams facility, composed
of a superconducting linac driver, delivering
deuterons with an energy up to 40
MeV (5 mA) and heavy ions with an energy
of 14.5 MeV/u (1 mA). This facility is now fully approved by the French government. IPN Orsay is in charge of the
study and manufacture of the beta 0.12 cryomodule of the superconducting LINAC. These cryomodule, designed for