Low loss coatings for the VIRGO large mirrors

présentée par L. PinardThe goal of the VIRGO program is to build a giant Michelson type interferometer (3 kilometer long arms) to detect gravitational waves. Large optical components (350 mm in diameter), having extremely low loss at 1064 nm, are needed. Today, the Ion beam Sputtering is the only deposition technique able to produce optical components with such performances. Consequently, a large ion beam sputtering deposition system was built to coat large optics up to 700 mm in diameter. The performances of this coater are described in term of layer uniformity on large scale and optical losses (absorption and scattering characterization). The VIRGO interferometer needs six main mirrors. The first set was ready in June 2002 and its installation is in progress on the VIRGO site (Italy). The optical performances of this first set are discussed. The requirements at 1064 nm are all satisfied. Indeed, the absorption level is close to 1 ppm (part per million), the scattering is lower than 5 ppm and the R.M.S. wavefront of these optics is lower than 8 nm on 150 mm in diameter. Finally, some solutions are proposed to further improve these performances, especially the absorption level (lower than 0.1 ppm) and the mechanical quality factor Q of the mirrors (thermal noise reduction)

La natation en triathlon, aspects théoriques et pratiques : influence du port de la combinaison en néoprène

Chatard J.-C. La natation en triathlon, aspects théoriques et pratiques : influence du port de la combinaison en néoprène. In: Les Cahiers de l'INSEP, n°20, 1997. Un sport, deux enchaînements, trois disciplines : le triathlon. Actes du 1er symposium international de l'entraînement en triathlon. pp. 41-55

Effects of kicking, performance and drag during draft swimming in elite triathletes

Millet Grégoire, Chatard J.-C., CHOLLET D. Effects of kicking, performance and drag during draft swimming in elite triathletes. In: Les Cahiers de l'INSEP, n°24, 1999. 2e Congrès international de triathlon de l’INSEP – 2nd INSEP international triathlon Congress pp. 209-216

Modeling the training-performance relationship using a mixed model in elite swimmers

PURPOSE: The aim of this study was to model the relationship between training and performance in 13 competitive swimmers, over three seasons, and to identify individual and group responses to training. METHODS: A linear mixed model was used as an alternative to the Banister model. Training effect on performance was studied over three training periods: short-term, the average of training load accomplished during the 2 wk preceding each performance of the studied period; mid-term, the average of training load accomplished during weeks 3, 4, and 5 before each performance; and long-term, weeks 6, 7, and 8. RESULTS: Cluster analysis identified four groups of subjects according to their reactions to training. The first group corresponded to the subjects who responded well to the long-term training period, the second group to the long- and mid-term periods, the third to the short- and mid-term periods, and the fourth to the combined periods. In the model, the intersubject differences and the evolution over the three seasons were statistically significant for the identified groups of swimmers. Influence of short-term training was negative on performance in the four groups, whereas mid- and long-term training had, on the average, a positive effect in three groups out of four. Between seasons 1 and 3, the effect of mid-term training declined, whereas the effect of long-term training increased. The fit between real and modeled performances was significant for all swimmers (0.1

Kinematic Changes during a 100-m Front Crawl

International audienc

Performance, résistance passive et type de battement chez des triathlètes « élite » en natation avec drafting

Millet Grégoire, Chatard J.-C., Chollet Didier. Performance, résistance passive et type de battement chez des triathlètes « élite » en natation avec drafting. In: Les Cahiers de l'INSEP, n°24, 1999. 2e Congrès international de triathlon de l’INSEP – 2nd INSEP international triathlon Congress pp. 200-208

Screening young athletes for prevention of sudden cardiac death: Practical recommendations for sports physicians

International audienc