Spin-1 resonances

The European Physical Journal Special Topics ◽

10.1140/epjs/s11734-021-00223-9 ◽

2021 ◽

Author(s):

Stefania De Curtis ◽

Daniele Dominici

Keyword(s):

Finite Width ◽

Interference Effects ◽

Composite Higgs ◽

Model Independent

AbstractSpin-1 resonances are naturally present in composite Higgs frameworks. We first review a model independent approach to parameterize a single additional heavy triplet and then we consider more realistic models arising in composite Higgs scenarios where a larger number of spin-1 resonances is expected. In these cases, finite width and interference effects can heavily affect the bounds extracted from the data.

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On the reinterpretation of non-resonant searches for Higgs boson pairs

Journal of High Energy Physics ◽

10.1007/jhep02(2021)049 ◽

2021 ◽

Vol 2021 (2) ◽

Author(s):

Alexandra Carvalho ◽

Florian Goertz ◽

Ken Mimasu ◽

Maxime Gouzevitch ◽

Anamika Aggarwal

Keyword(s):

Cross Section ◽

Parameter Space ◽

Effective Field Theory ◽

New Physics ◽

Effective Field ◽

Higgs Bosons ◽

Fast Simulation ◽

Composite Higgs ◽

Analytic Parametrization ◽

Model Independent

Abstract The detection of production of a pair of Higgs bosons before the end of LHC operation would be a clear evidence of New Physics (NP). As searches for non-resonant production of Higgs pairs are being designed it is of particular importance to be able to conveniently present current experimental results in terms of limits in the most ‘model-independent’ fashion possible. To this end, in this article we provide an analytic parametrization of the differential Higgs-pair production at the LHC in the effective field theory (EFT) extension of the SM. It results from a fit to the theory prediction for the gg → hh cross section at the 13 TeV LHC. Subsequently the resulting formula is used for a reweighing technique that allows to recast exclusion bounds from ATLAS and CMS hh →$$ \gamma \gamma b\overline{b} $$ γγb b ¯ searches to any point of the considered EFT parameter space. We demonstrate with a fast simulation of the LHC detectors that with this approach it is possible to cover the continuous EFT parameter space, taking correctly into account the efficiencies of signal selections, without the necessity of rerunning a large number of full detector simulations. Finally, the resulting exclusion bounds are confronted with several explicit models, such as setups with additional scalars, including 2HDM, vector-like fermions, and minimal composite Higgs models, which are mapped to the EFT.

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Model-independent approach for incorporating interference effects in collider searches for new resonances

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08763-5 ◽

2020 ◽

Vol 80 (12) ◽

Author(s):

Stefano Frixione ◽

Lydia Roos ◽

Edmund Ting ◽

Eleni Vryonidou ◽

Martin White ◽

...

Keyword(s):

Standard Model ◽

Direct Evidence ◽

Invariant Mass Distribution ◽

Hadron Collider ◽

Large Mass ◽

Beyond The Standard Model ◽

Interference Effects ◽

Scalar Resonance ◽

The Standard Model ◽

Model Independent

AbstractThe presence of large-mass resonances in the data collected at the Large Hadron Collider would provide direct evidence of physics beyond the Standard Model. A key challenge in current resonance searches at the LHC is the modelling of signal–background interference effects, which can severely distort the shape of the reconstructed invariant mass distribution relative to the case where there is no interference. Such effects are strongly dependent on the beyond the Standard Model theory that must be considered as unknown if one aims to minimise any theoretical bias on the search results. In this paper, we describe a procedure which employs a physically-motivated, model-independent template functional form that can be used to model interference effects, both for the characterisation of positive discoveries, and in the presentation of null results. We illustrate the approach with the example of a scalar resonance decaying into a pair of photons.

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Towards model-independent approach to the analysis of interference effects in pair production of new heavy quarks

Journal of High Energy Physics ◽

10.1007/jhep07(2014)142 ◽

2014 ◽

Vol 2014 (7) ◽

Cited By ~ 14

Author(s):

D. Barducci ◽

A. Belyaev ◽

J. Blamey ◽

S. Moretti ◽

L. Panizzi ◽

...

Keyword(s):

Pair Production ◽

Heavy Quarks ◽

Interference Effects ◽

Model Independent

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The Unsteady Forces Due To Propeller-Appendage Interaction

Journal of Applied Mechanics ◽

10.1115/1.3636526 ◽

1963 ◽

Vol 30 (2) ◽

pp. 279-287 ◽

Cited By ~ 2

Author(s):

O. Pinkus ◽

J. R. Lurye ◽

S. Karp

Keyword(s):

Essential Feature ◽

Relative Size ◽

Tip Clearance ◽

Finite Width ◽

Interference Effects ◽

Propeller Blade ◽

Flat Plates ◽

Unsteady Forces ◽

Method Of Solution ◽

Analytic Expressions

This paper presents a study of the nature of the unsteady forces in the field of a propeller rotating in the vicinity of an appendage. The propeller is assumed to be one of a high aspect ratio while the appendage, although of finite width, is assumed to be infinitely long, and thus the problem is reduced to a study of the unsteady flow field around two flat plates. An essential feature of the analysis is that the mutual interference effects of propeller blade and the appendage are taken into account. The method of solution employs the technique of the substitution vortex which yields explicit analytic expressions for the quasisteady, apparent-mass and wake forces for both the propeller and appendage. These equations provide the magnitude and variation of the total forces as functions of tip clearance, distance, and relative size of appendage and propeller.

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Single production of vector-like quarks: the effects of large width, interference and NLO corrections

Journal of High Energy Physics ◽

10.1007/jhep08(2021)107 ◽

2021 ◽

Vol 2021 (8) ◽

Author(s):

Aldo Deandrea ◽

Thomas Flacke ◽

Benjamin Fuks ◽

Luca Panizzi ◽

Hua-Sheng Shao

Keyword(s):

Invariant Mass Distribution ◽

Finite Width ◽

Interference Effects ◽

Hadron Colliders ◽

Exotic Particles ◽

The Standard Model ◽

Single Production ◽

Quantitative Results ◽

Large Width

Abstract We provide a comprehensive discussion, together with a complete setup for simulations, relevant for the production of a single vector-like quark at hadron colliders. Our predictions include finite width effects, signal-background interference effects and next-to-leading order QCD corrections. We explicitly apply the framework to study the single production of a vector-like quark T with charge 2/3, but the same procedure can be used to analyse the single production of vector-like quarks with charge −4/3, −1/3, 2/3 and 5/3, when the vector-like quark interacts with the Standard Model quarks and electroweak bosons. Moreover, this procedure can be straightforwardly extended to include additional interactions with exotic particles. We provide quantitative results for representative benchmark scenarios characterised by the T mass and width, and we determine the role of the interference terms for a range of masses and widths of phenomenological significance. We additionally describe in detail, both analytically and numerically, a striking feature in the invariant mass distribution appearing only in the T → th channel.

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Some Aspects of Exelfs Analysis in the Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000477 ◽

1980 ◽

Vol 38 ◽

pp. 118-119

Author(s):

D. E. Johnson ◽

S. Csillag

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Energy Loss ◽

Analytical Electron Microscopy ◽

Interference Effects ◽

Interatomic Distances ◽

X Ray ◽

Structure Information ◽

Microanalytical Technique ◽

Analytical Electron

Recently, the applications area of analytical electron microscopy has been extended to include the study of Extended Energy Loss Fine Structure (EXELFS). Modulations past an ionization edge in the energy loss spectrum (EXELFS), contain atomic fine structure information similar to Extended X-ray Absorbtion Fine Structure (EXAFS). At low momentum transfer the main contribution to these modulations comes from interference effects between the outgoing excited inner shell electron waves and electron waves backscattered from the surrounding atoms. The ability to obtain atomic fine structure information (such as interatomic distances) combined with the spatial resolution of an electron microscope is unique and makes EXELFS an important microanalytical technique.

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