The former HERMES target polarimeter (BRP) which is now part of tha PAX polarized gas target setup, employed two sets of rf-resonators, one for Hydrogen, and one for deuterium operation. The frequency for two level transitions (DeltaF=+/-1) is in the order of the HFS splitting energy DeltaW at B=0 which correspond at 1 421.4 MHz for hydrogen (H) and 327.4 MHZ for deuterium (D). The HERMES target has been operated in long periods for one target species oly. In order to switch from H to D or vice versa, the resonating structures had be exchanged, and a tedious tuning procedure had to be performed. Some of the Filtering Test that can be possibly foreseen at CERN AD would require to run the BRP subsequently with H and D with non time between for modifications. Therefore a system of resonators is required which can serve both H and D, the existing hardware could be used, like the static field magnets and the vacuum system. The development of such a "Dual Cavity" will be described in the contribution. Similar cavities based on "Tuned Twin Lines" have been used in Atomic Beam Sources. Their principles of operation will be discusse.
Dual H&D Cavity for the PAX Target Polarimeter
CARASSITI, Vittore;CIULLO, Giuseppe;LENISA, Paolo;
2012
Abstract
The former HERMES target polarimeter (BRP) which is now part of tha PAX polarized gas target setup, employed two sets of rf-resonators, one for Hydrogen, and one for deuterium operation. The frequency for two level transitions (DeltaF=+/-1) is in the order of the HFS splitting energy DeltaW at B=0 which correspond at 1 421.4 MHz for hydrogen (H) and 327.4 MHZ for deuterium (D). The HERMES target has been operated in long periods for one target species oly. In order to switch from H to D or vice versa, the resonating structures had be exchanged, and a tedious tuning procedure had to be performed. Some of the Filtering Test that can be possibly foreseen at CERN AD would require to run the BRP subsequently with H and D with non time between for modifications. Therefore a system of resonators is required which can serve both H and D, the existing hardware could be used, like the static field magnets and the vacuum system. The development of such a "Dual Cavity" will be described in the contribution. Similar cavities based on "Tuned Twin Lines" have been used in Atomic Beam Sources. Their principles of operation will be discusse.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
