Electroweak interaction

About: Electroweak interaction is a research topic. Over the lifetime, 16333 publications have been published within this topic receiving 468927 citations. The topic is also known as: electroweak force.

Cosmic vortons and particle physics constraints

Abstract: We investigate the cosmological consequences of particle physics theories that admit stable loops of superconducting cosmic string - {\it vortons}. General symmetry breaking schemes are considered, in which strings are formed at one energy scale and subsequently become superconducting in a secondary phase transition at what may be a considerably lower energy scale. We estimate the abundances of the ensuing vortons, and thereby derive constraints on the relevant particle physics models from cosmological observations. These constraints significantly restrict the category of admissible Grand Unified theories, but are quite compatible with recently proposed effects whereby superconducting strings may have been formed close to the electroweak phase transition.

LHC Signals from Warped Extra Dimensions

Abstract: We study production of Kaluza-Klein gluons (KKG) at the Large Hadron Collider (LHC) in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. We show that the detection of KK gluon is challenging since its production is suppressed by small couplings to the proton's constituents. Moreover, the KK gluon decaysmostly to top pairs due to an enhanced coupling and hence is broad. Nevertheless, we demonstrate that for MKKG<~;; 4 TeV, 100 fb-1 of data at the LHC can provide discovery of the KK gluon. We utilize a sizeable left-right polarization asymmetry from the KK gluon resonance to maximize the signal significance, and we explore the novel feature of extremely highly energetic"top-jets." We briefly discuss how the detection of electroweak gauge KK states (Z/W) faces a similar challenge since their leptonic decays ("golden" modes) are suppressed. Our analysis suggests that other frameworks, for example little Higgs, which rely on UV completion via strong dynamics might face similar challenges, namely (1) Suppressed production rates for the new particles (such as Z'), due to their"lightfermion-phobic" nature, and (2) Difficulties in detection since the new particles are broad and decay predominantly to third generation quarks andmore » longitudinal gauge bosons.« less

flavio: a Python package for flavour and precision phenomenology in the Standard Model and beyond

Abstract: flavio is an open source tool for phenomenological analyses in flavour physics and other precision observables in the Standard Model and beyond. It consists of a library to compute predictions for a plethora of observables in quark and lepton flavour physics and electroweak precision tests, a database of experimental measurements of these observables, a statistics package that allows to construct Bayesian and frequentist likelihoods, and of convenient plotting and visualization routines. New physics effects are parameterised as Wilson coefficients of dimension-six operators in the weak effective theory below the electroweak scale or the Standard Model EFT above it. At present, observables implemented include numerous rare $B$ decays (including angular observables of exclusive decays, lepton flavour and lepton universality violating $B$ decays), meson-antimeson mixing observables in the $B_{d,s}$, $K$, and $D$ systems, tree-level semi-leptonic $B$, $K$, and $D$ decays (including possible lepton universality violation), rare $K$ decays, lepton flavour violating $\tau$ and $\mu$ decays, $Z$ pole electroweak precision observables, the neutron electric dipole moment, and anomalous magnetic moments of leptons. Not only central values but also theory uncertainties of all observables can be computed. Input parameters and their uncertainties can be easily modified by the user. Written in Python, the code does not require compilation and can be run in an interactive session. This document gives an overview of the features as of version 1.0 but does not represent a manual. The full documentation of the code can be found in its web site.