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The stransverse mass, M T2, in special cases

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Abstract

This document describes some special cases in which the stransverse mass, M T2, may be calculated by non-iterative algorithms. The most notable special case is that in which the visible particles and the hypothesised invisible particles are massless — a situation relevant to its current usage in the Large Hadron Collider as a discovery variable, and a situation for which no analytic answer was previously known. We also derive an expression for M T2 in another set of new (though arguably less interesting) special cases in which the missing transverse momentum must point parallel or anti parallel to the visible momentum sum. In addition, we find new derivations for already known M T2 solutions in a manner that maintains manifest contralinear boost invariance throughout, providing new insights into old results. Along the way, we stumble across some unexpected results and make conjectures relating to geometric forms of M eff and H T and their relationship to M T2.

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Authors and Affiliations

  1. University of Cambridge, Department of Physics, Cavendish Laboratory, J.J. Thomson Avenue, Cambridge, U.K.

    Christopher G. Lester

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  1. Christopher G. Lester
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Correspondence to Christopher G. Lester.

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ArXiv ePrint: 1103.5682

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Lester, C.G. The stransverse mass, M T2, in special cases. J. High Energ. Phys. 2011, 76 (2011). https://doi.org/10.1007/JHEP05(2011)076

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