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arXiv · 1008.2206

Momentum reconstruction at the LHC for probing CP-violation in the stop sector

Gudrid Moortgat-Pick·Krzysztof Rolbiecki·Jamie Tattersall
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Abstract

We study the potential to observe CP-violating effects in SUSY stop cascade decay chains at the LHC. Asymmetries composed by triple products of momenta of the final state particles are sensitive to CP-violating effects. Due to large boosts that dilute the asymmetries, these can be difficult to observe. If all particle masses in a cascade decay are known, it may be possible to reconstruct all momenta in the decay chains on an event-by-event basis even when we have missing momentum due to a stable LSP. After the reconstruction, the non-diluted CP-violating signal can be recovered and gets significantly enhanced so that an observation may become feasible. A fully hadronic study has been completed to define the areas of the mSUGRA parameter space that may yield a 3-sigma observation with 500 fb^(-1) at the LHC.

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Gudrid Moortgat-Pick, Krzysztof Rolbiecki, Jamie Tattersall. 2011-07-21. Momentum reconstruction at the LHC for probing CP-violation in the stop sector. https://doi.org/10.1103/physrevd.83.115012

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