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arXiv · 1212.2873

Ascertaining the spin for new resonances decaying into tau+ tau- at Hadron Colliders

Swagato Banerjee·Jan Kalinowski·Wojciech Kotlarski·Tomasz Przedzinski·Zbigniew Was
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Abstract

Evidence of a new particle with mass ~125 GeV decaying into a pair of tau leptons at the Large Hadron Collider spurs interest in ascertaining its spin in this channel. Here we present a comparative study between spin-0 and spin-2 nature of this new particle, using spin correlations and decay product directions. The TauSpinner algorithm is used to re-weight distributions from qqbar -> gamma/Z -> tau+ tau- sample to simulate a spin-2 state exchange. The method is based on supplementing the Standard Model matrix elements with those arising from presence of a new interaction. Studies with simulated samples demonstrate the discrimination power between these spin hypotheses based on data collected at the Large Hadron Collider.

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Swagato Banerjee, Jan Kalinowski, Wojciech Kotlarski, Tomasz Przedzinski, Zbigniew Was. 2012-12-12. Ascertaining the spin for new resonances decaying into tau+ tau- at Hadron Colliders. https://doi.org/10.1140/epjc%2Fs10052-013-2313-1

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