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)

Virgo Commissioning Progress

none130sìmixedF. Acernese ; P. Amico; M. Alshourbagy; F. Antonucci; S. Aoudia ; P. Astone; S. Avino ; D. Babusci ; G. Ballardin ; F. Barone ; L. Barsotti; M. Barsuglia ; F.Beauville ; S. Bigotta; M.A.Bizouard ; C.Boccara ; F.Bondu ; L.Bosi; C. Bradaschia; S. Birindelli; S. Braccini; A. Brillet ; V. Brisson ; D.Buskulic ; E.Calloni ; E.Campagna ; F. Carbognani ; F.Cavalier ; R.Cavalieri ; G.Cella; E.Cesarini ; E.Chassande-Mottin ; N. Christensen ; A.-C.Clapson ; F.Cleva ; C. Corda; A. Corsi; F.Cottone; J.-P.Coulon ; E.Cuoco ; A. Dari; V.Dattilo ; M.Davier ; M. del Prete ; R.De Rosa ; L.Di Fiore ; A.Di Virgilio; B.Dujardin ; A.Eleuteri ; I.Ferrante; F.Fidecaro; I.Fiori; R.Flaminio; ; J.-D.Fournier ; S.Frasca; F.Frasconi; L.Gammaitoni; F. Garufi ; E. Genin; A.Gennai; A.Giazotto; G.Giordano ; L. Giordano ; R. Gouaty ; D. Grosjean ; G.Guidi ; S.Hebri ; H.Heitmann ; P.Hello ; S. Karkar ; S.Kreckelbergh ; P.La Penna ; M. Laval ; N. Leroy ; N.Letendre ; B. Lopez ; M. Lorenzini ; V.Loriette ; G.Losurdo ; J.-M.Mackowski ; E.Majorana ; C.N.Man ; M. Mantovani; F. Marchesoni; F.Marion ; J. Marque ; F.Martelli ; A.Masserot ; M.Mazzoni ; F. Menzinger ; L.Milano ; C. Moins ; J.Moreau ; N.Morgado ; B.Mours ; F. Nocera ; C.Palomba; F.Paoletti;; S. Pardi ; A. Pasqualetti ; R.Passaquieti; D.Passuello; F. Piergiovanni ; L.Pinard ; R.Poggiani; M.Punturo; P.Puppo; K.Qipiani ; P.Rapagnani; V.Reita ; A.Remillieux ; F. Ricci; I.Ricciardi ; P. Ruggi ; G.Russo ; S.Solimeno ; A. Spallicci ; M. Tarallo; M. Tonelli; A. Toncelli; E.Tournefier ; F.Travasso; C. Tremola; G. Vajente; D. Verkindt ; F. Vetrano ; A.Viceré ; J.-Y.Vinet ; H. Vocca; M. YvertAcernese, F.; Amico, P.; Alshourbagy, M.; Antonucci, F.; Aoudia, S.; Astone, P.; Avino, S.; Babusci, D.; Ballardin, G.; Barone, F.; Barsotti, L.; Barsuglia, M.; Beauville, F.; Bigotta, S.; Bizouard, M. A.; Boccara, C.; Bondu, F.; Bosi, L.; Bradaschia, C.; Birindelli, S.; Braccini, S.; Brillet, A.; Brisson, V.; Buskulic, D.; Calloni, E.; Campagna, E.; Carbognani, F.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cesarini, E.; Chassande-Mottin, E.; Christensen, N.; Clapson, A. -C.; Cleva, F.; Corda, C.; Corsi, A.; Cottone, F.; Coulon, J. -P.; Cuoco, E.; Dari, A.; Dattilo, V.; Davier, M.; del Prete, M.; De Rosa, R.; Di Fiore, L.; Di Virgilio, A.; Dujardin, B.; Eleuteri, A.; Ferrante, I.; Fidecaro, F.; Fiori, I.; Flaminio, R.; Fournier, J. -D.; Frasca, S.; Frasconi, F.; Gammaitoni, L.; Garufi, F.; Genin, E.; Gennai, A.; Giazotto, A.; Giordano, G.; Giordano, L.; Gouaty, R.; Grosjean, D.; Guidi, G.; Hebri, S.; Heitmann, H.; Hello, P.; Karkar, S.; Kreckelbergh, S.; La Penna, P.; Laval, M.; Leroy, N.; Letendre, N.; Lopez, B.; Lorenzini, M.; Loriette, V.; Losurdo, G.; Mackowski, J. -M.; Majorana, E.; Man, C. N.; Mantovani, M.; Marchesoni, F.; Marion, F.; Marque, J.; Martelli, F.; Masserot, A.; Mazzoni, M.; Menzinger, F.; Milano, L.; Moins, C.; Moreau, J.; Morgado, N.; Mours, B.; Nocera, F.; Palomba, C.; Paoletti, F.; Pardi, S.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Piergiovanni, F.; Pinard, L.; Poggiani, R.; Punturo, M.; Puppo, P.; Qipiani, K.; Rapagnani, P.; Reita, V.; Remillieux, A.; Ricci, F.; Ricciardi, I.; Ruggi, P.; Russo, G.; Solimeno, S.; Spallicci, A.; Tarallo, M.; Tonelli, M.; Toncelli, A.; Tournefier, E.; Travasso, F.; Tremola, C.; Vajente, G.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinet, J. -Y.; Vocca, H.; Yvert, M

The present status of the VIRGO Central Interferometer

The VIRGO Central Interferometer (CITF) is a short suspended interferometer operated with the central area elements of the VIRGO detector. The main motivation behind the CITF is to allow the integration and debugging of a large part of the subsystems of VIRGO while the construction of the long arms of the antenna is being completed. This will permit a faster commissioning of the full-size antenna. In fact, almost all the main components of the CITF, with the exception of the large mirrors and a few other details, are the same as those to be used for the full-size detector. In this paper the present status of the VIRGO CITF is reported

Data analysis methods for non-Gaussian, nonstationary and nonlinera features and their application to VIRGO

International audienc