Top quark and heavy vector boson pair production in
pp
collisions at the LHC is a good probe for new physics An accurate measurement of the top quark mass is also important and considered as a major ...task by theorists. This paper summarizes experimental results on production cross sections of events with top quarks as well as with pairs of heavy vector bosons
ZZ
,
ZW
and
WW
. They are mostly based on datasets accumulated by the ATLAS and CMS detectors at
TeV during Run2 of the LHC. A summary of results of precise measurements of the top quark mass is also given.
The last undiscovered particle of the Standard Model, the Higgs boson, was observed in 2012 by the ATLAS and CMS Collaborations at the Large Hadron Collider at CERN. Since that time the cross ...sections of main five production mechanisms at
, 8 and 13 TeV
pp
collisions were measured as well as branching ratios of five decay channels, a mass and a width. It was also established that spin and parity of the Higgs boson are 0
. In addition, differential cross sections on many kinematic variables were measured. No deviations from the Standard Model predictions were observed. The precision of the measurements at the LHC is permanently improving with analyzing new data. This paper summarizes experimental situation with the Higgs boson after ten years of its discovery mostly based on full
, 8 and 13 TeV datasets accumulated by the ATLAS and CMS detectors during Run1 and Run2 of the LHC.
Measurement of electroweak production of single heavy vector bosons in
-collisions at the LHC is an important test for new physics. The most interesting case is the so-called vector boson fusion ...process which involves trilinear gauge coupling constant. This paper summarizes experimental results on electroweak production cross sections of events with leptonic decays of
- and
-bosons plus two hadron jets. They are based on datasets accumulated by the ATLAS and CMS detectors at
,
and
TeV during Run1 and Run2 of the LHC.
Multiple heavy vector boson production in
collisions at the LHC is a good testing ground for new physics. The simplest way to obtain four such bosons, namely
, in the final state is to have two
pairs ...in a single event. Three heavy vector bosons can be produced in events with two pairs of top quarks, with one
-pair and additional top quark, with one
-pair plus a heavy boson, with one top quark plus two vector bosons as well as directly. This paper summarizes results on the mentioned multiple heavy vector boson production by the ATLAS and CMS experiments at the Large Hadron Collider. They are mostly based on datasets accumulated at
TeV during the whole Run2.
Recent results on Higgs boson production and decays in the ATLAS and CMS experiments at the LHC are reviewed. These results are based on data accumulated from 2015 to 2018 in studying proton–proton ...collisions at the c.m. energy of 13 TeV. The production cross sections for the Higgs boson are measured for four basic production mechanisms along with the branching ratios for its five decay modes most convenient for studies. The Standard Model Higgs boson couplings are determined from a global analysis of all of the above channels. All experimental results are found to be compatible with the predictions of the Standard Model. Prospects of the ATLAS and CMS experiments for Higgs boson studies are also discussed.
The accuracy of finite-difference analysis in electromagnetics can be qualitatively improved by employing arbitrary local approximating functions, not limited to Taylor expansion polynomials. In the ...proposed new class of flexible local approximation methods (FLAME), desirable local analytical approximations (such as harmonic polynomials, plane waves, and cylindrical or spherical harmonics) are directly incorporated into the finite-difference scheme. Although the method usually (but not necessarily) operates on regular Cartesian grids, it is in some cases much more accurate than the finite-element method with its complex meshes. This paper reviews the theory of FLAME and gives a tutorial-style explanation of its usage. While one motivation for the new approach is to minimize the notorious "staircase" effect at curved and slanted interface boundaries, it has much broader applications and implications. As illustrative examples, the paper examines the simulation of: 1) electrostatic fields of finite-size dielectric particles in free space or in a solvent with or without salt; 2) scattering of electromagnetic waves; 3) plasmon resonances; and 4) wave propagation in a photonic crystal.
Traditional boundary integral methods suffer from the singularity of Green's kernels. The paper develops, for a model problem of 2D scattering as an illustrative example, singularity-free boundary ...difference equations. Instead of converting Maxwell's system into an integral boundary form first and discretizing second, here the differential equations are first discretized on a regular grid and then converted to boundary difference equations. The procedure involves nonsingular Green's functions on a lattice rather than their singular continuous counterparts. Numerical examples demonstrate the effectiveness, accuracy and convergence of the method. It can be generalized to 3D problems and to other classes of linear problems, including acoustics and elasticity.
The authors as part of the HWW team of the ATLAS experiment at the LHC have studied events with two opposite-sign muons and two electrons in the search for the Standard Model Higgs boson
H
and a ...heavy resonance
R
in the channel of decay into two
W
-bosons. The analysis was carried out using the complete statistics of proton–proton collision events for 2015–2018 exposure for the c.m.s. energy of protons
= 13 TeV. The application of a deep neural network made it possible to significantly improve our earlier results for separation of the
H
-boson signal in the vector-boson-fusion production mechanism. Various theoretical models were used to calculate the new expected upper limits for the production of
R
resonance with a spin 0, 1, or 2 in addition to those obtained earlier in a toy NWA model for a heavy Higgs boson.
In this paper, micromagnetic analysis of an array of long magnetic nanowires (NWs) embedded in a nonmagnetic matrix is performed. It is found that for NWs with diameters on the order of a hundred ...nanometers, the anisotropy and exchange energies are negligible, so the total free energy is a sum of the Zeeman and magnetostatic energies. The minimum magnetostatic energy corresponds to the maximum Zeeman energy, whereby half of the NWs are magnetized parallel to the external field, while the rest of the NWs are magnetized antiparallel to the external fields. The study shows a vortex behavior of the magnetic moments in the magnetization reversal process. Additionally, the hysteresis loop area of the nanocomposite is inversely proportional to the NW diameter in the range from 20 to 200 nm. The results pave the way for designing of NW-based devices such as optimized magnetic sensors for biomedical applications with a trade-off between miniaturization and energy loss.
The discovery of a Higgs boson with a mass of about 125 GeV has prompted the question of whether or not this particle is part of a larger and more complex Higgs sector than that envisioned in the ...Standard Model. In this talk, the current results from the ATLAS experiment on Beyond the Standard Model (BSM) Higgs boson searches are outlined. The results are interpreted in well-motivated BSM Higgs frameworks.
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