BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Low secondary electron yield carbon coatings for electron-cloud mi tigation in modern particle accelerators DTSTART;VALUE=DATE-TIME:20090514T120000Z DTEND;VALUE=DATE-TIME:20090514T140000Z DTSTAMP;VALUE=DATE-TIME:20130619T121924Z UID:indico-event-58544@cern.ch DESCRIPTION:Electron-cloud is one of the main limitations for future parti cle accelerators with positively charged beams of high intensity. The main material parameter governing the phenomenon is the Secondary Electron Yie ld (SEY) of the inner surface of the vacuum chamber. An ideal surface shou ld always maintain a low SEY\, the threshold for SPS with nominal LHC beam being 1.3\, also after air exposure for installation of the chambers and maintenance. As a possible solution amorphous carbon coatings were produce d by magnetron sputtering of graphite targets. In laboratory measurements they exhibit maximum SEY between 0.9 and 1.1 after transfer to the measuri ng instrument through air. After 1 month air exposure the SEY rises to val ues between 1.0 and 1.4 depending on the storage conditions\, coating para meters and configuration. \nTests performed in the SPS on electron cloud m onitors demonstrated an excellent performance. The behaviour of the carbon coating is similar to that of thermally activated TiZrV NEG\, but is achi eved without bake-out and is largely superior compared to stainless steel\ , which is the present material of the vacuum chamber surface. In 2009 thr ee coated dipoles have been prepared and inserted in the machine in order to verify the long term behaviour of the coating in the SPS with respect t o e-cloud\, pressure and resistance to radiation.\n\nhttp://indico.cern.ch /conferenceDisplay.py?confId=58544 LOCATION:CERN BE Auditorium Meyrin URL:http://indico.cern.ch/conferenceDisplay.py?confId=58544 END:VEVENT BEGIN:VEVENT SUMMARY:Superconducting Combined Function Magnet System for the J-PARC Neu trino Beam Line DTSTART;VALUE=DATE-TIME:20090615T120000Z DTEND;VALUE=DATE-TIME:20090615T133000Z DTSTAMP;VALUE=DATE-TIME:20130619T121924Z UID:indico-event-61613@cern.ch DESCRIPTION:A superconducting magnet system for the J-PARC neutrino beam l ine has been constructed since 2004. The system consists of 14 pairs of c ryostats\; each contains 2 combined function magnets (SCFM). The SCFM uses two (upper and lower) single layer left/right asymmetric coils that produ ce a dipole field of 2.6 T and quadrupole of 19 T/m. The SCFMs had been de veloped at KEK by 2004\, were mass-produced by industries and completed by summer 2008. The system has been installed into the beam line tunnel by the end of 2008 and the hardware commissioning was completed by March 200 9. The beam commissioning has been successfully carried out since April 20 09\, and 30 GeV primary proton beam has been successfully transported to t he production target for neutrino beam directing the T2K/KAMIOKA neutrino experiment facility . We present the system overview including cryogenic s\, and report the magnet development including the production\, installat ion\, hardware commissioning\, and beam commissioning\, with our sincere a ppreciation for the kindest cooperation given by CERN.\n\nhttp://indico.ce rn.ch/conferenceDisplay.py?confId=61613 LOCATION:CERN BE Auditorium Meyrin URL:http://indico.cern.ch/conferenceDisplay.py?confId=61613 END:VEVENT BEGIN:VEVENT SUMMARY:Update of the cryogenic risk analysis following the 19 September 2 008 incident DTSTART;VALUE=DATE-TIME:20091112T130000Z DTEND;VALUE=DATE-TIME:20091112T150000Z DTSTAMP;VALUE=DATE-TIME:20130619T121924Z UID:indico-event-73392@cern.ch DESCRIPTION:On 19 September 2008\, during powering tests of the main dipol e circuit in sector 3-4 of the LHC\, an electrical fault occurred producin g an electrical arc and resulting in mechanical and electrical damage\, re lease of helium from the magnet cold mass to the insulation vacuum enclosu re and consequently to the tunnel\, via the spring-loaded relief discs on the vacuum enclosure. The helium discharge from the cold mass to the vacuu m enclosure exceeded by an order of magnitude\, the maximum credible incid ent (MCI) flow described in the preliminary risk analysis performed in 199 8. Basing on the experience gained from the 19 September incident\, a new MCI has been formulated and the cryogenic risk analysis has been revised a nd updated. The performed simulations enabled the revision of the helium d ischarge system protecting the vacuum enclosure against the over-pressuriz ation. \nDuring the incident the amount of about 6 ton of helium has been released into the LHC tunnel in the way that can be classified as a physic al phenomenon with a high rate volume production. The performed analysis h as shown that any shock phenomena can be excluded\, and the pressure distr ibution has been uniform along the tunnel during the discharge process. Th e recommendations concerning the mechanical properties of the doors instal led in the tunnel have been formulated.\n\nhttp://indico.cern.ch/conferenc eDisplay.py?confId=73392 LOCATION:CERN Main Auditorium URL:http://indico.cern.ch/conferenceDisplay.py?confId=73392 END:VEVENT END:VCALENDAR