Mechanics and Cooling Systems for the CBM STS

Mechanics and Cooling Systems for the CBM STS CONTENT 1. Si detector’s plates 2. Module of detector 3. Carbon fiber frame 4. Detector’s plates holder 5. Ladder support system 6. The parts of cooling system 7. Arrangement of detectors plates on a ladder 8. Typical construction of the ladder 9. Construction of STS station Nr 4 10. Tilling and distances between sensors 11. Ladders installation and fixation SAINT-PETERSBURG STATE UNIVERSITY S. Igolkin , e-mail Igolkin @hiex. phys. spbu. ru Serguei. Igolkine@cern. ch Dubna , Russia October, 2008

Installation of Si detectors is offered to Carbon fiber space structure - Frame Similar structures have been successful used at creation design Of Inner Trecker System ITS of experiment ALICE Such space CF Frames have the best parities weightrigidity and allow to create on their basis the finished assembly of detectors Ladders, including: - Hybrids ( silicon detectors or modules of detectors with cables and plates of end electronic - Basic fixing elements - Cooling system of plates of end electronics

Detector’s module 32 E

Carbon fiber frame Material: CF prepreg M 55 J/ 334 EU Moduls of composit 27000 Gpa

Detector’s plates holder Materials: Fiber glass (E-glass + epoxy glue )

Ladders support system Each end of ladder have a final support. Final support consist of: some plate with precise basis elements (surfaces) and two prism’s Assemblage of end support’s and frame perform on the assembly jig at the same time with detectors holders. The precise of assembly jig ensure precise disposition the all elements of ladder

The parts of cooling system Coolant fluid

Arrangement of detector’s plates on a ladder Option 1 - fixation detects plates in parallel of horizontal plane in chess order - Provide compact configuration but demands are bend of the cables Option 2 – fixation of detectors plats under an inclination -Provide compact configuration and don’t demands are bend of the cables, but not conveniently for installation. Option 3 – fixation detectors plates in parallel Of the horizontal plane, each detector shifting in parallel in one direction. - Provide easy installation, but demands more place and increases zones of overlapping between ladders

Typical construction of the ladder

The position of detectors for Station 4 The position of Si detectors plates from centre: 1. 22 x 62 + 42 x 62 + 62 x 62 + [62 x 62]x 3 2. 2/3/4 42 x 62 +62 x 62 + [62 x 62]x 3 5 62 x 62 + [62 x 62]x 3 6 6 [62 x 62]x 3 As we see, each subsequent ladder it turns out by exceptions of the central plates of detector 1 2 3 4 5 6

The length of the ladders for ST 4 Length of the ladder from centre to periphery of station decrease proportionally 40 mm i. e. to a step of the carbon frame, but the length of the cables in the hybrids are kept. Nr 1 Nr 2, 3, 4 Nr 5 Nr 6

Construction of STS station Nr 4 The station consist of 4 frames. On each are fixed 3 ladder’s with detectors. The frames with ladders are fixed on the slides of main support of STS

Tilling and distance between sensors

Ladder’s installation and fixation

Schematic fixation of frames on the main support STS Some slides for ladder’s frame are fixed on the main support of STS. The frames with ladders are positioned on the slide : for top support - ball on plane with flat springs for down support – ball on prism