Beam Phase Monitor for CLIC and CTF3: pick-up design

presented at CLIC09 Workshop, 12-16 October 2009, CER

Design and electromagnetic analysis of the new DAFNE interaction region

A new interaction region (IR) vacuum chamber has been designed for the DAFNE upgrade aimed at testing of the crabbed waist collision scheme. Compared to the existing IR vacuum chamber, the new one has a simplified design and consists essentially of the confluence of straight tubes, having a double Y shape. Sharp discontinuities have been avoided to limit the beam impedance of the structure. However, the study of the electromagnetic interaction with the beam is necessary in order to avoid excessive power loss due to possible higher order modes (HOM) trapped in the Y-shape chamber. The first design of the chamber has been analyzed with HFSS and HOMs have been found and characterized. On the basis of these results some modifications in the geometry of the IR chamber have been introduced to eliminate or attenuate these trapped resonances. The results of these simulations are presented. New electromagnetic shielding for the bellows inserted in the IR chambers, have been developed as well. The design criteria and the simulation results for these shielded bellows are also reported

The SMILING project : prevention of falls by a mechatronic training device

Ageing is characterized by functional changes that can create gait and balance disturbances, which are the main risk factors of falling. Elderly people at risk of falling can be considered to be suffering from an involuntary motor behaviour that restricts their participation in society. One method to overcome such a situation is to activate a new learning process to train for real life tasks, which represents innovation. The SMILING system is intended to challenge the elderly to solve new problems in real time by inducing variable environments that need active response and problem solving. Variable environments induced by perturbations will weaken stiff motor behaviour(s), induce flexibility and thus enable effective training and improve mobility in real life environments. The SMILING solution provides a changeable yet safe environment that needs active response and problem solving by the user. It consists of a wearable non-invasive computer-controlled system that applies chaotic perturbations to the lower extremities during walking through small alterations of the height and slope of weight-bearing surfaces. The complete system consists of 3 modules: i) a complete walking analysis system; ii) a pair of motorised training shoes; iii) a user friendly portable control unit

Robot-era project: Preliminary results on the system usability

The European project Robot-Era is an ambitious integrated project (FP7-ICT-2011.5.4), which objective is the development of advanced robotic services, integrated in intelligent environments, to provide independent living to older people. In order to guarantee the matching of the users� need and the demands, two loops of experimentation were conceived, in realistic and real setting. The aim of the paper is to described the methods applied and the main results coming from the first experimental loop, concerning the degree of usability of the interfaces and provide guidelines for testing socially assistive robots with older people. � Springer International Publishing Switzerland 2015

Organic enrichment can increase the impact of microplastics on meiofaunal assemblages in tropical beach systems

The cumulative impact of microplastic and organic enrichment is still largely unknown. Here, we investigated the microplastic contamination, the organic enrichment and their effects on meiofaunal distribution and diversity in two islands of the Maldivian archipelago: one more pristine, and another strongly anthropized. Field studies were coupled with manipulative experiments in which microplastic polymers were added to sediments from the non-anthropized island (i.e., without organic enrichment) to assess the relative effect of microplastic pollution on meiofauna assemblages. Our results reveal that the impact of microplastic contamination on meiofaunal abundance and taxa richness was more significant in the anthropized island, which was also characterized by a significant organic enrichment. Meiofauna exposed experimentally to microplastic contamination showed: i) the increased abundance of opportunistic nematodes and copepods and ii) a shift in the trophic structure, increasing relevance in epistrate-feeder nematodes. Based on all these results, we argue that the coexistence of chronic organic enrichment and microplastics can significantly increase the ecological impacts on meiofaunal assemblages. Since microplastic pollution in the oceans is predicted to increase in the next decades, its negative effects on benthic biodiversity and functioning of tropical ecosystems are expected to worsen especially when coupled with human-induced eutrophication. Urgent actions and management plans are needed to avoid the cumulative impact of microplastic and organic enrichment

Stabilization of the arrival time of a relativistic electron beam to the 50 fs level

We report the results of a low-latency beam phase feed-forward system built to stabilize the arrival time of a relativistic electron beam. The system was operated at the Compact Linear Collider (CLIC) Test Facility (CTF3) at CERN where the beam arrival time was stabilized to approximately 50 fs. The system latency was 350 ns and the correction bandwidth >23 MHz. The system meets the requirements for CLIC.Comment: 5 pages, 9 figures, 1 tabl

Commissioning Status of the CTF3 Delay Loop

The CLIC Test Facility CTF3, built at CERN by an international collaboration, aims at demonstrating the linear collider by 2010. In particular, one of the main goals is to study the generation of high-current electron pulses by interleaving bunch trains in delay lines and rings using transverse RF deflectors. This will be done in the 42 m long delay loop, built under the responsibility of INFN/LNF, and the 84 m long combiner ring that will follow it. The delay loop installation was completed and its commissioning started at the end of 2005. In this paper the commissioning results are presented, including the first tests of beam recombination

CTF3: Design of Driving Beam Combiner Ring

In CTF3 the beam compression of the driving beam structure between the main linac and the decelerating section is obtained with a delay loop and a combiner ring which increase the pulse current by a factor 10. The design of the combiner ring is presented. Tunable isochronicity condition, corrected up to second order, should assure preservation of the correlation in the longitudinal phase space during the compression. Path-length tuning devices are included in the combiner ring layout to compensate for orbit variations