Advert The ATLAS Detector is a large piece of apparatus for Particle Physics experiments being constructed for the Large Hadron Collider (LHC) at the CERN Laboratory in Switzerland. A critical component of the ATLAS Detector will be the Semi-Conductor Tracker (SCT), made up of a Barrel and two identical End-caps. The SCT consists of a number of stable structures supporting silicon detectors; these silicon detectors will track sub-atomic particles to precisions of a few microns over volumes of several cubic metres.
The main components of each End-cap support structure are: a) a carbon-fibre reinforced plastic (CFRP) sandwich cylinder and b) flat CFRP sandwich panels. The flat panels fasten to the ends of the cylinder and are used to support the whole assembly on rails. The sandwich of both the cylinder and the flat support panels is expected to be constructed with CFRP skins made from high-modulus graphite fibres and cyanate-ester resin with a high-performance aramid/phenolic honeycomb core. Also required for each End-cap is c) a cylinder of single CFRP laminate which will form part of a thermal enclosure.
Due to the resolution required in tracking sub-atomic particles, the support structures will be required to:
Manufacture of the following components is required:
Support Cylinder (Qty: 2)
A CFRP sandwich cylinder 1940 mm long, 1140 mm outside diameter. The sandwich will consist of two skins, each 0.2 mm thick, and a core of 9 mm thickness. The cylinder wall will be perforated with a number of rectangular and round apertures, some of these apertures will be fitted with inserts for various parts to be fastened to the cylinder during detector assembly; those apertures not fitted with inserts will be sealed by close-outs. The ends of the cylinder will be fitted with inserts for connection to the Support Panels.
Rear Support Panel (Qty: 2)
A flat single piece CFRP sandwich panel consisting of a central circular section of 1220 mm diameter and two support arms extending from this central section to a width of 2240 mm. The sandwich will consist of two 0.9 mm thick skins and a core of 26 mm thickness. The Support Panel will have integral inserts and a central aperture cut-out. The edges and aperture will be sealed by edge closures.
Front Support Panel (Qty: 2)
A flat CFRP sandwich panel in three separate sections (central part and two in-fill panels) forming a central circular section of 1220 mm diameter and two support arms extending to a width of 2240 mm. The sandwich will consist of two 0.45 mm thick skins and a core of 8 mm thickness. All parts of the Support Panel will have integral inserts and the mid-section will have a central aperture cut-out. The edges and aperture will be sealed by edge closures.
Inner Thermal Enclosure Cylinder (Qty: 2)
A single CFRP laminate cylinder 1970 mm long, 502 mm diameter and 0.45 mm thick. One end of the cylinder will be fitted with a 0.45 mm thick CFRP flange.
NB. All Dimensions are approximate, the exact design details are being finalised. The current status can be found at http://hepwww.rl.ac.uk/atlas-sct/engineering/ec/Tender.htm