1 H. Pernegger/CERNIBL cooling review 15/5/2012 IBL Cooling Requirements H. Pernegger

2 H. Pernegger/CERNIBL cooling review 15/5/2012 Requirements for IBL Cooling IBL requirements come from planar sensors –Sensor operating up to 1000V –Planar sensors pose most stringent requirements Driven by Sensor operation requirements –Cold to minimize leakage current and its effect on noise –Avoid thermal run-away Beam pipe Bake-out –Detecotr off but cooled to avoid damage to detector from beam pipe heating –Started with layout –Will produce board in the next weeks (Rui) Requirements Document: ATL-IP-ES-0186

3 H. Pernegger/CERNIBL cooling review 15/5/2012 General requirements for IBL cooling “IBL Cooling system” comprises –CO2 cooling plant –Cooling distributions –Controls and monitoring –(environmental gas -> based on existing installation) 14 staves of IBL = 14 cooling circuits starting at manihold at muuon detector sector 5 IBL PP1 = interface from detector to cooling system

4 H. Pernegger/CERNIBL cooling review 15/5/2012 General requirements General Parameters Currently under new simulation and measurements on mock-up

5 H. Pernegger/CERNIBL cooling review 15/5/2012 Operation modes Cold operation –This is the normal running mode during physics operations and detector tests with ATLAS closed. Warm operation – This mode concerns commissioning running during initial detector tests after installation. The distribution line temperature outside the IST shall be kept above the dew point of the cavern to avoid condensation. Annealing operation – This mode is used for beneficial annealing of sensors (leakage current, depletion voltage). The detector is operated warm for a fixed number of days per year with variable power to achieve a specific sensor temperature. Standby operation –This mode is used keep the detector cold during maintenance operations in ATLAS. The IBL detector is off, the cooling system is operated to keep sensors cold. Bake-out operation – This mode is used during the bake-out of the beam pipe. The detector power is switched off and the cooling system removes the heat dissipated from the beam pipe. Redundancy needed in case of cooling failure.

6 H. Pernegger/CERNIBL cooling review 15/5/2012 Operation modes Approximate evaporation temperature [range] and expected sensor temperatures

7 H. Pernegger/CERNIBL cooling review 15/5/2012 Controls Cont. evap. Temperature set point between -40 and loops with on/off valves at muon detector –Manual sufficient according to Olga’s information Monitoring of evap temperature on cooling pipes inside IST: 1 on inlet and 1 on outlet = 28 sensors –Mounting to be agreed with IBL WG DSS signals to be defined together with DSS group –Output (e.g. plat failure) –Input (e.g. DSS stop signal) Filter stages: replaceable filter stages to guarantee cleanliness of on-detector pipework and capillaries

8 H. Pernegger/CERNIBL cooling review 15/5/2012 Schedule Driver: IBL ready for installation: Sept 2013 currently planned At “RFI” date the CO2 cooling plant must be fully commissioned and ready to receive detector for tests –Including controls, monitoring and DCS interfaces Propose CO2 system ready by Sept 2013 up to PP1 connection and all controls Proposed Schedule (for discussion) –Now to July 2012: design completion, final part list & order of components –July 2012 – March 2013: Plant, Distribution and Controls Construction –March 2013 to July 2013: Installation of plant in USA15 and distribution in detector –July-Sept 2013: Commissioning and failure mode tests

9 H. Pernegger/CERNIBL cooling review 15/5/2012 Backup slides

10 H. Pernegger/CERNIBL cooling review 15/5/2012 Calculation of thermal run-away Calculated thermal run-away limits for different stave- performance