150 research outputs found
ATLAS and CMS Statistics Wish-List
A wish-list of statistics related issues, which were regarded by ATLAS and CMS as requiring a deeper understanding and perhaps the response of a professional statistician, is given
LHC Statistics for Pedestrians
A pedestrians guide aimed at the LHC laymen statisticians is presented. It is not meant to replace any text book but to help the confused physicist to understand the jargon and methods used by HEP Phystatisticians
Asymptotic formulae for likelihood-based tests of new physics
We describe likelihood-based statistical tests for use in high energy physics
for the discovery of new phenomena and for construction of confidence intervals
on model parameters. We focus on the properties of the test procedures that
allow one to account for systematic uncertainties. Explicit formulae for the
asymptotic distributions of test statistics are derived using results of Wilks
and Wald. We motivate and justify the use of a representative data set, called
the "Asimov data set", which provides a simple method to obtain the median
experimental sensitivity of a search or measurement as well as fluctuations
about this expectation.Comment: fixed typo in equations 75 & 7
The LHC Discovery Potential of a Leptophilic Higgs
In this work, we examine a two-Higgs-doublet extension of the Standard Model
in which one Higgs doublet is responsible for giving mass to both up- and
down-type quarks, while a separate doublet is responsible for giving mass to
leptons. We examine both the theoretical and experimental constraints on the
model and show that large regions of parameter space are allowed by these
constraints in which the effective couplings between the lightest neutral Higgs
scalar and the Standard-Model leptons are substantially enhanced. We
investigate the collider phenomenology of such a "leptophilic"
two-Higgs-doublet model and show that in cases where the low-energy spectrum
contains only one light, CP-even scalar, a variety of collider processes
essentially irrelevant for the discovery of a Standard Model Higgs boson
(specifically those in which the Higgs boson decays directly into a
charged-lepton pair) can contribute significantly to the discovery potential of
a light-to-intermediate-mass (m_h < 140 GeV) Higgs boson at the LHC.Comment: 25 pages, LaVTeX, 11 figures, 1 tabl
Practical Statistics for High Energy Physics
In these lecture notes the frequentist methods used in the Higgs search, discovery and measurement are reviewed. The idea is that the reader will be able to understand what lies beneath the surface of the results and the plots shown in the experiments publications. Though the results shown are mainly from ATLAS and CMS, the methods and the lessons can be propagated to other fields such as Astro-Particles and fixed target experiments
Estimating the significance of a signal in a multi-dimensional search
In experiments that are aimed at detecting astrophysical sources such as
neutrino telescopes, one usually performs a search over a continuous parameter
space (e.g. the angular coordinates of the sky, and possibly time), looking for
the most significant deviation from the background hypothesis. Such a procedure
inherently involves a "look elsewhere effect", namely, the possibility for a
signal-like fluctuation to appear anywhere within the search range. Correctly
estimating the -value of a given observation thus requires repeated
simulations of the entire search, a procedure that may be prohibitively
expansive in terms of CPU resources. Recent results from the theory of random
fields provide powerful tools which may be used to alleviate this difficulty,
in a wide range of applications. We review those results and discuss their
implementation, with a detailed example applied for neutrino point source
analysis in the IceCube experiment
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