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Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells in a Shallow Shelf Carbonate Approaching Waterflood Depletion
Precise reconstruction of sparticle masses without ambiguities
We critically reexamine the standard applications of the method of
kinematical endpoints for sparticle mass determination. We consider the typical
decay chain in supersymmetry (SUSY) squark -> neutralino -> slepton -> LSP,
which yields a jet j and two leptons ln and lf. The conventional approaches use
the upper kinematical endpoints of the individual distributions m_{jll},
m_{jl(lo)} and m_{jl(hi)}, all three of which suffer from parameter space
region ambiguities and may lead to multiple solutions for the SUSY mass
spectrum. In contrast, we do not use m_{jll}, m_{jl(lo)} and m_{jl(hi)}, and
instead propose a new set of (infinitely many) variables whose upper kinematic
endpoints exhibit reduced sensitivity to the parameter space region. We then
outline an alternative, much simplified procedure for obtaining the SUSY mass
spectrum. In particular, we show that the four endpoints observed in the three
distributions m^2_{ll}, m^2_{jln} U m^2_{jlf} and m^2_{jln}+m^2_{jlf} are
sufficient to completely pin down the squark mass and the two neutralino
masses, leaving only a discrete 2-fold ambiguity for the slepton mass. This
remaining ambiguity can be easily resolved in a number of different ways: for
example, by a single additional measurement of the kinematic endpoint of any
one out of the many remaining 1-dimensional distributions at our disposal, or
by exploring the correlations in the 2-dimensional distribution of m^2_{jln} U
m^2_{jlf} versus m^2_{ll}. We illustrate our method with two examples: the LM1
and LM6 CMS study points. An additional advantage of our method is the expected
improvement in the accuracy of the SUSY mass determination, due to the
multitude and variety of available measurements.Comment: 37 pages, added a new figure in the Appendix, published versio