FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W183278051> ?p ?o ?g. }

• W183278051 abstract "The Phase II upgrade to the LHC collimation system calls for complementing the 30 high robust Phase I graphite secondary collimators with 30 high Z Phase II collimators. The Phase II collimators must be robust in various operating conditions and accident scenarios. This paper reports on the final construction and testing of the prototype collimator to be installed in the SPS (Super Proton Synchrotron) at CERN. Bench-top measurements will demonstrate that the device is fully operational and has the mechanical and vacuum characteristics acceptable for installation in the SPS. THE COPPER ROTATABLE COLLIMATOR DESIGN The principle function of the LHC collimation system is to protect the superconducting magnets from quenching due to particle losses. The collimation system must absorb upwards of 90 kW in the steady state operating condition (1 hr beam lifetime) and withstand transient periods where up to 450 kW is deposited for no more than 10 seconds. The system must also be robust against an accident scenario where up to 8 full intensity bunches impact on one collimator jaw due to an asynchronous firing of the beam abort system imparting 1 MJ over 200 ns. The high Z material of the phase II collimators provides better collimation efficiency compared to the low Z graphite phase I collimators but will not withstand the impact of the 8 full intensity bunches in the accident scenario without permanent damage, so a rotatable jaw has been designed which will be recoverable. Composed of two cylindrical jaws, if a beam happens to hit a jaw it can be rotated to introduce a clean surface for continued operation. 20 flat facets on the cylindrical jaw surface is sufficient to last the lifetime of the LHC. Details of the jaw design and construction can be found in [1] and [2]. The final jaw design is illustrated in figure 1. Details of the device can be seen in figure 2 which shows the jaw end, cylindrical vacuum chamber and transition pieces. The Jaw is supported by a thin stainless steel bar that can flex and take up the thermal expansion of the jaw without the need of a universal joint. The use of a cylindrical vacuum chamber simplifies the design and construction and facilitates the use of thinner chamber walls compared to a rectangular design resulting in less radiation activation. Work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP). † js344@slac.stanford.edu Figure 1: Cutaway of Jaw showing outer jaw surfaces and cooling tube routed through the center of the molybdenum shaft. A temperature probe is positioned near the end of the jaw on the transition piece to monitor the temperature of the jaw during beam cleaning. The sensor would ideally be placed directly on the jaw but this proved impractical. Each end of the device incorporates a BPM assembly housing standard LHC warm section buttons. These BPMs will be used to align the jaw relative to the beam with a resolution of 25 microns or better. The rotation mechanism described in other papers [1] allows for precision alignment of the jaw via use of a Geneva Gear. The RF foils will be 250 micron thick beryllium-copper sheets wide enough to completely block the rotation mechanism and supports from the line of sight of the beam. Studies have shown that a large RF foil is necessary to limit longitudinal trapped mode heating [4]. A sliding contact between the rotating jaw and the fixed RF foil is necessary. This contact uses 300 conducting rhodium coated 1 mm stainless steel ball bearings. The bearing race is bare copper so the rhodium coating on the balls is to prevent cold welding. The target DC resistance across the RF contact is 1 mOhm. A 4-wire measurement was performed to measure the contact resistance for both jaws and the resistance was found to be within acceptable levels. However, the contact resistance was highly dependent on the bearing race tightness and machine smoothness. We are investigating modifications to this setup to make a more resilient sliding contact. An additional set of ceramic ball bearings about the central molybdenum hub are to support the load of the jaw during rotation. Impedance considerations and SLAC-PUB-14174" @default.
• W183278051 created "2016-06-24" @default.
• W183278051 creator A5010797963 @default.
• W183278051 creator A5041561983 @default.
• W183278051 creator A5045470156 @default.
• W183278051 creator A5050494628 @default.
• W183278051 creator A5071605868 @default.
• W183278051 creator A5080100698 @default.
• W183278051 creator A5088650891 @default.
• W183278051 creator A5089328146 @default.
• W183278051 date "2010-01-01" @default.
• W183278051 modified "2023-09-27" @default.
• W183278051 title "CONSTRUCTION AND BENCH TESTING OF A ROTATABLE COLLIMATOR FOR THE LHC COLLIMATION UPGRADE" @default.
• W183278051 cites W124059660 @default.
• W183278051 cites W1519817161 @default.
• W183278051 hasPublicationYear "2010" @default.
• W183278051 type Work @default.
• W183278051 sameAs 183278051 @default.
• W183278051 citedByCount "5" @default.
• W183278051 countsByYear W1832780512014 @default.
• W183278051 crossrefType "journal-article" @default.
• W183278051 hasAuthorship W183278051A5010797963 @default.
• W183278051 hasAuthorship W183278051A5041561983 @default.
• W183278051 hasAuthorship W183278051A5045470156 @default.
• W183278051 hasAuthorship W183278051A5050494628 @default.
• W183278051 hasAuthorship W183278051A5071605868 @default.
• W183278051 hasAuthorship W183278051A5080100698 @default.
• W183278051 hasAuthorship W183278051A5088650891 @default.
• W183278051 hasAuthorship W183278051A5089328146 @default.
• W183278051 hasConcept C111919701 @default.
• W183278051 hasConcept C116915560 @default.
• W183278051 hasConcept C120665830 @default.
• W183278051 hasConcept C121332964 @default.
• W183278051 hasConcept C127413603 @default.
• W183278051 hasConcept C168834538 @default.
• W183278051 hasConcept C185544564 @default.
• W183278051 hasConcept C2777574091 @default.
• W183278051 hasConcept C2779200277 @default.
• W183278051 hasConcept C2780615140 @default.
• W183278051 hasConcept C34445779 @default.
• W183278051 hasConcept C41008148 @default.
• W183278051 hasConcept C520434653 @default.
• W183278051 hasConcept C87668248 @default.
• W183278051 hasConceptScore W183278051C111919701 @default.
• W183278051 hasConceptScore W183278051C116915560 @default.
• W183278051 hasConceptScore W183278051C120665830 @default.
• W183278051 hasConceptScore W183278051C121332964 @default.
• W183278051 hasConceptScore W183278051C127413603 @default.
• W183278051 hasConceptScore W183278051C168834538 @default.
• W183278051 hasConceptScore W183278051C185544564 @default.
• W183278051 hasConceptScore W183278051C2777574091 @default.
• W183278051 hasConceptScore W183278051C2779200277 @default.
• W183278051 hasConceptScore W183278051C2780615140 @default.
• W183278051 hasConceptScore W183278051C34445779 @default.
• W183278051 hasConceptScore W183278051C41008148 @default.
• W183278051 hasConceptScore W183278051C520434653 @default.
• W183278051 hasConceptScore W183278051C87668248 @default.
• W183278051 hasLocation W1832780511 @default.
• W183278051 hasOpenAccess W183278051 @default.
• W183278051 hasPrimaryLocation W1832780511 @default.
• W183278051 hasRelatedWork W117222095 @default.
• W183278051 hasRelatedWork W1570748186 @default.
• W183278051 hasRelatedWork W17650961 @default.
• W183278051 hasRelatedWork W2105494837 @default.
• W183278051 hasRelatedWork W2121676978 @default.
• W183278051 hasRelatedWork W2147089985 @default.
• W183278051 hasRelatedWork W2165256555 @default.
• W183278051 hasRelatedWork W2169733948 @default.
• W183278051 hasRelatedWork W2171474081 @default.
• W183278051 hasRelatedWork W2171638259 @default.
• W183278051 hasRelatedWork W2270553011 @default.
• W183278051 hasRelatedWork W2280026134 @default.
• W183278051 hasRelatedWork W2288307692 @default.
• W183278051 hasRelatedWork W2383343471 @default.
• W183278051 hasRelatedWork W253726787 @default.
• W183278051 hasRelatedWork W2547581505 @default.
• W183278051 hasRelatedWork W28386876 @default.
• W183278051 hasRelatedWork W318452165 @default.
• W183278051 hasRelatedWork W1635779825 @default.
• W183278051 hasRelatedWork W2142133916 @default.
• W183278051 isParatext "false" @default.
• W183278051 isRetracted "false" @default.
• W183278051 magId "183278051" @default.
• W183278051 workType "article" @default.