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The Radio Frequency Quadrupole (RFQ) linac and 1.6 MW RF power system of the Linear IFMIF Prototype Accelerator (LIPAc) facility in the International Fusion Energy Research Center (IFERC) in Rokkasho (Japan) has been installed and conditioned. During the assembly and uning process, the RFQ cavity was protected with a temporary tent from the potential deterioration of performance caused by dust. The vacuum in the cavity was improved through the 100 °C baking rocess of the cavity. The high power test of the 175 MHz RF systems up to 200 kW in CW for each of the eight RF chains was performed for checking its stable output reproducibility in Japan, before connecting 9–3/16 inch coaxial transmission lines from the RF chains to the RF input couplers of the cavity. It was confirmed that the eight RF chains provided the balanced RF power to the single RFQ cavity inphase using a feedback loop and a synchronization system. The peak power in the cavity achieved 150 kW in the pulsed mode, which corresponds approximately to the required electric field to accelerate proton beam. Such RF conditioning process is ongoing to achieve 600 kW approximately required for deuteron beam commissioning planned in 2018.

This study investigates the links between parents’ perceptions of social and built local environment and child sex-specific levels of excess weigh/obesity. Further, we analyse if the availability of child sports is a potential contribute to the observed patterns of excess weight/obesity. In a first step, we observed 1885 school children (aged 3-10 yrs) living in Coimbra district. In this sample, results have shown a significant association between parental perceptions of built and social local environment and obesity in girls. In a second step, we found that the availability of sports in Coimbra city is unbalanced, heavily restricting the opportunities of sports practice to girls. From the 67 sports opportunities observed in Coimbra, 32 were directed to both sexes, 23 were directed towards boys and 12 to girls. We’ve concluded that girls experience processes of environmental discrimination, which may have a harmful health impact. In this context, we argue the need for environmental interventions, not only as a means of promoting health, but also gender equity., Cet étude recherche les associations entre les perceptions parentales de l’environnement construit et social de l’endroit de résidence et la prévalence de l’obésité infantile selon le genre des enfants. On étude aussi la disponibilité de modalités sportives infantiles, en vérifiant leur possible contribution pour les valeurs observées d’excès de poids/obésité. Dans une première phase os a observé 1885 enfants en âge préscolaire (3-10 ans), résidants au district de Coimbra. Dans cet échantillon on a verifié une association significative entre la perception parentale de l’environnement construit et social et les valeurs d’obésité au sexe féminin. Dans une deuxième phase os a verifié que la disponibilité de modalités sportives à ville de Coimbra est déséquilibrée, en restreignant fortement les opportunités de pratique sportive aux enfants du sexe féminin. Dans 67 opportunités de pratique sportive observées à cette ville-là, on a vérifié que 32 étaient mixtes, 23 étaient dirigées pour le sexe masculin et 12 pour le sexe féminin. On conclut que les enfants du sexe féminin souffrent des procédés de discrimination environnementale, dont l’impact sur la santé peut être néfaste. Dans ce contexte-ci, on argument le besoin d’interventions environnementales, comme uns manière de promouvoir la santé et aussi l´équité entre les genres., Este estudo investiga as associações entre as percepções parentais do ambiente construído e social do local de residência e a prevalência de obesidade infantil segundo o género das crianças. Estuda-se ainda a oferta de modalidades desportivas infantis, verificando a sua potencial contribuição para os valores observados de excesso de peso/obesidade. Numa primeira fase, observaram-se 1885 crianças em idade escolar (3-10 anos) residentes no distrito de Coimbra. Nesta amostra, verificou-se uma associação significativa entre a percepção parental do ambiente construído e social e os valores de obesidade no sexo feminino. Numa segunda fase, verificou-se que a oferta de modalidades desportivas na cidade de Coimbra é desequilibrada, restringindo fortemente as oportunidades de prática desportiva às crianças do sexo feminino. Em 67 oportunidades de prática desportiva observadas na cidade, verificou-se que 32 eram mistas, 23 eram direccionadas para o sexo masculino e 12 para o sexo feminino. Conclui-se que as crianças do sexo feminino sofrem processos de discriminação ambiental cujo impacte na saúde pode ser nefasto. Neste contexto, argumenta-se a necessidade de intervenções ambientais, não só como forma de promoção da saúde, mas também de equidade entre os géneros.

The power coupler is a crucial element in the design of an RF cavity. Power from an RF source is transported towards the cavity by a waveguide and transferred into the cavity by means of a power coupler that is adapted to both the transport mode in the waveguide and the principal resonant mode in the cavity. In the case of Linac4, a rectangular half-height waveguide (WG) WR2300 is used and the connection from this WG to the cavity is achieved by iris coupling through an interconnecting waveguide (IWG) in the tank wall. In this note simulations and measurements on a prototype and studies on Tank1 of the Linac4 Drift Tube Linac (DTL) are discussed in order to define the dimensions of this IWG such that it optimises the power transfer into the cavity.

Linac4 Drift Tube Linac (DTL) cavities will be equipped with Post Couplers (PCs) for field stabilization. The study presented in this paper starts with the analysis of 2D and 3D simulations of post couplers in order to develop an equivalent circuit model which can explain the post coupler stabilization working principle and define a tuning strategy for DTL cavities. Simulations and equivalent circuit results have been verified by measurements on the Linac4 DTL prototypes at CERN.

Post Cou­plers (PC's) are de­vices used in order to re­duce the ef­fect of per­tur­ba­tions on the op­er­at­ing mode of a DTL, using the res­o­nant cou­pling sta­bi­liza­tion method. In this paper an equiv­a­lent cir­cuit for a DTL equipped with PC's is pre­sent­ed, to­geth­er with a 3D sim­u­la­tion anal­y­sis, which can ex­plain the post cou­pler sta­bi­liza­tion prin­ci­ple and de­fine a new tun­ing strat­e­gy for DTL cav­i­ties. The PC tun­ing pro­ce­dure based on the equiv­a­lent cir­cuit and on fre­quen­cy mea­sure­ments has been test­ed and val­i­dat­ed with mea­sure­ments on the Linac4 DTL alu­minum model.

A one meter long hot prototype of the LINAC4 DTL, built in a collaboration with INFN Legnaro, was delivered to CERN in 2008. It was then copper plated at CERN is and is presently prepared for high-power testing at the CERN test stand in SM18. In this paper we present 2D/3D simulations and the first RF low-power measurements to verify the electromagnetic properties of the cavity and to tune it before the high-power RF tests. In particular, the influence of the post couplers was studied in order to guarantee stabilization of the accelerating field during operation. We present an equivalent circuit model of the DTL, together with a comparison of 3D simulations and measurement results for the hot model.