UPDATE ON SURVEY NEEDS w.r.t. CRAB CAVITIES INSTALLATION

5th HL-PLC meeting, 2/07/2013

D. Missiaen on behalf of H. Mainaud

2

Within +/- 0.1 mm ? (1σ)

Initial alignment (absolute position)

SmoothingFiducialisation

Alignment Strategy

Within +/- 0.1 mm (1σ)

Monitoring of the relative position

Re-adjustment if needed

Within a few µmBeam

3

Survey needs Monitoring & smoothing

Space requirements:

• In H direction

• [Stretched wire and associated sensors] : Integration of a continuous straight line (cylinder dia. 100 mm), straight above fiducials of components, on the transport side (for an easy access in case of maintenance), plus space for wire stretchers along Q1 and the last component.

• [left / right link]: one additional fiducial on the cryostat in front of each boreholes coming from the UPS galleries, and a continuous line between the borehole and associated fiducial.

Crab cavitiesCrab cavities

4

Survey needs Monitoring & smoothing

Space requirements: In V direction

• [Water surface and associated sensors]: horizontal lines (cylinder dia. 100 mm), by levels (as the tunnel is in slope) linking from time to time fiducials on the cryostats

Crab cavitiesCrab cavities

550 mm

950 mm

Cryo Jumper

RF In/Out

[Prelim] IR Layout of Crab CavitiesRama Calaga, HL-LHC PLC Meeting, Jan 2013

Space reservation for alignment systems

Tunnel cross section

Confirm the space reservation for the cryo-jumpers of the cavity cryostat (not to scale on the cross section) [Rama Calaga]

Alignment requirements for the crab cavities [Rama Calaga]: Precise the alignment requirements for the crab cavities, concerning the

fiducialisation, the initial alignment. Is a monitoring of the alignment of the crab cavities needed? Taking account of the radiation level in the area, will a remote adjustment

needed?

Book the corresponding space reservation on all the other cryostats (from Q1 to Q4) [Hélène Mainaud Durand and integration team?]

Next steps