RASNIK in LHCb Outer Tracker
This page describes the simplest system of RASNIK lines in LHCb OT.
A more detailed description can be found in this
An older version of this page can be found
RASNIK is a 3 point infrared optical alignment system.
RASNIK for ATLAS
(learn more from NIKHEF/ATLAS pages about RASNIK.)
Outer Tracker support structures
Outer Tracker frames
Location of Racks.
Slides about RASNIK in Outer Tracker
There are 3 stations in OT and 4 C-frames in each station.
In each corner of C-frame there will be 1 RASNIK line.
This makes 48 RASNIK lines.
These lines are parallel to the beam (z axis) and short (from 9cm - to about 0.6 m).
They measure relative movement of C-frames vs bridge (pilars or rails).
Two vertical, 8m long lines will measure displacements of the bridge vs bunker in horizontal directions.
- x,y of RASNIK on C-frames. Convention for installation of masks inside C-frames.
- z of RASNIK elements.
Materials shown on the 6th of June 2005. (only part 1 - without cables)
Corrected cable location. (part 2 - cables)
List of main RASNIK elements.
- 2 horizontal lines on top of the bridge could measure if it is bending. (Such lines are not installed, that was just an idea.)
Area with RASNIK shelves (green) with lenses and cameras and cables (red) installed on pillars, bridge and tables.
Lines monitoring bridge are on the corners of bunker: cameras on L-profiles (orange), mask and lenses inside square tubes (blue).
Above drawing as .ipt
(to see from any side)
Drawing of old version with Hall probes as .ipt
RASNIK and IT chain
updated: 1 dec 2007