Specification for the cables:
Semi Flexible coaxial cable for LHC Collimators

Supply of hermetic coaxial cable assemblies with SMA connectors, able to withstand mechanical cycling and Ultra High Vacuum compatible.

The cables needed for the Phase II collimators should:

• Be compliant with the Ultra High Vacuum of the LHC machine (in terms of choice of materials, reliability, cleanliness and outgassing rate).
• Operate under strong radiation (20 MGy expected during the life of the collimator).
• Withstand a bakeout temperature of 250 C during 48H.
• Transmit correctly the high frequency Beam Position Monitor signal without phase shift.
• Be small, robust and flexible enough to follow the jaw motion during the thousands of cycles expected. 

Performance specifications
Impedance: (50  ± 1) .
Frequency Range: DC to 3 GHz
VSWR: 1.1:1 max to 1 GHz
Insulation resistance: >10^12 ohms
Voltage: 1500 V rms
Operating temperature range:  +20°C  to +70°C
Bakeout temperature:  250°C sustained for 48 H.
Hermeticity:
(or: cable outgassing rate lower than 1x10-9 Pa.m3/s per cable after 100 h under vacuum)
Radiation Hardness: >20 megarads gamma
Connector interface: male SMA type
Cable length: 1250 +- 3 mm
All four cables in a quadruplet shall be of equal electrical length. The electrical length difference within a quadruplet must be less or equal to 20 Pico Second.
 

Materials
UHV materials
Outer jacket: AISI 304L vacuum grade stainless steel
External cable diameter: <2.5 mm
Center conductor: Cu
Insulator: SiO2 or mineral insulation equivalent
Connector contact: gold-plated BeCu
Cables assemblies shall be delivered to CERN UHV cleaned and ready for installation in a high vacuum environment.

We would be really grateful if you could provide a list of firms before June 6th 2012.