CMS upgrade and future plans

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CMS upgrade and future plans

Kerstin Hoepfner1_RQEHKDOIRI_{the CMS collaboration}

1_{RWTH Aachen University, Phys.Inst. 3A, Otto-Blumenthal-Str., 52074 Aachen, Germany}

Abstract. CMS plans for operation at the LHC phase-II unprecedented in terms of luminosity thus resulting in serious consequences for detector performance. To achieve the goal to maintain the present excellent performance of the CMS detector, several upgrades are necessary. To handle the high phase-II data rates, the readout and trigger systems are redesigned using recent technology developments. The high particle rates will accelerate detector aging and require replacement of the tracker and forward calorimeters. In addition, the muon system will be extended.

1 The LHC phase-II conditions and detector consequences

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2 The phase-II tracker

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Figure 3.Physics performance of the upgraded tracker.

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3 The phase-II calorimeters

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Figure 6. Option 1 for the upgrade of the forward calorimeters uses a shashlik geometry for the ECAL part.

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Figure 7. Option 2 of the endcap calorimeter, foreseeing a high-granularity design based on silicon as an active material.

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4 Upgrade of the muon system

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Figure 8. Upgrade of the muon system.

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Figure 9. Left: Increasing the acceptance from eta=2.4 to eta=4 allows to collect an additional ~35% of

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Figure 10. Benefits of the additional detectors in the muon system for offline muon reconstruction.

5 Conclusions and summary

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References

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2. CMS Collaboration, ³7HFKQLFDOSURSRVDOIRUWKH&06SKDVH-,,XSJUDGH´GRFXPHQWLQ preparation