Search results for " Standard Model"
showing 10 items of 645 documents
New exclusion limits on scalar and pseudoscalar axionlike particles from light shining through a wall
2015
Physics beyond the Standard Model predicts the possible existence of new particles that can be searched at the low-energy frontier in the sub-eV range. The OSQAR photon regeneration experiment looks for ``light shining through a wall'' from the quantum oscillation of optical photons into ``weakly interacting sub-eV particles,'' such as axion or axionlike particles (ALPs) in a 9 T transverse magnetic field over a length of $2\ifmmode\times\else\texttimes\fi{}14.3\text{ }\text{ }\mathrm{m}$. In 2014, this experiment was run with an outstanding sensitivity, using an 18.5 W continuous wave laser emitting in the green at the single wavelength of 532 nm. No regenerated photons have been detected …
New high-sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons at the HIBEAM/NNBAR experiment at the European Spalla…
2021
Abstract The violation of baryon number, B , is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron–antineutron oscillation ( n → n ̄ ) via mixing, neutron–antineutron oscillation via regeneration from a sterile neutron state ( n → [ n ′ , n ̄ ′ ] → n ̄ ), and neutron disappearan…
A strong electroweak phase transition from the inflaton field
2016
We study a singlet scalar extension of the Standard Model. The singlet scalar is coupled non-minimally to gravity and assumed to drive inflation, and also couple sufficiently strongly with the SM Higgs field in order to provide for a strong first order electroweak phase transition. Requiring the model to describe inflation successfully, be compatible with the LHC data, and yield a strong first order electroweak phase transition, we identify the regions of the parameter space where the model is viable. We also include a singlet fermion with scalar coupling to the singlet scalar to probe the sensitivity of the constraints on additional degrees of freedom and their couplings in the singlet sec…
Edges and Endpoints in 21-cm Observations from Resonant Photon Production
2020
Physical review letters 127(1), 011102 (1-7) (2021). doi:10.1103/PhysRevLett.127.011102
Relaxion fluctuations (self-stopping relaxion) and overview of relaxion stopping mechanisms
2020
Journal of high energy physics 2005(5), 80 (2020). doi:10.1007/JHEP05(2020)080
The Large Hadron–Electron Collider at the HL-LHC
2021
The Large Hadron-Electron Collider (LHeC) is designed to move the field of deep inelastic scattering (DIS) to the energy and intensity frontier of particle physics. Exploiting energy-recovery technology, it collides a novel, intense electron beam with a proton or ion beam from the High-Luminosity Large Hadron Collider (HL-LHC). The accelerator and interaction region are designed for concurrent electron-proton and proton-proton operations. This report represents an update to the LHeC's conceptual design report (CDR), published in 2012. It comprises new results on the parton structure of the proton and heavier nuclei, QCD dynamics, and electroweak and top-quark physics. It is shown how the LH…
Observation of the rare B(s)(0) + decay from the combined analysis of CMS and LHCb data.
2015
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported licence.-- et al.
The Higgs Era
2016
Después del descubrimiento de un bosón escalar con masa alrededor de 125, el Modelo Estándar parece funcionar perfectamente, pero todavía hay mucho espacio (y necesidad) para nueva física. A pesar de su enorme éxito, el Modelo Estándar deja muchas preguntas sin responder y muchas cuestiones abiertas. A falta del conocimiento de una simetría fundamental de la Naturaleza que nos indique el camino, hemos de analizar fenomenologicamente cualquier extensión del Modelo que pueda responder al menos a alguna de estas preguntas. En este trabajo estudiamos dos tipos de extensiones del Modelo Estándar, las dos relacionadas con el sector escalar. En la primera parte de la tesis estudiamos la posible ex…
Review of Particle Physics
2020
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, …
Exotic properties of neutrinos using effective Lagrangians and specific models
2013
289 páginas. Tesis Doctoral del Departamento de Física Teórica, de la Universidad de Valencia, y del Instituto de Física Corpuscular (IFIC).