Related papers: S-matrix approach to the Z resonance
Z-boson decay $Z \rightarrow f\tilde{f}\gamma\gamma$ in the Standard Model is analysed. The distribution function on the invariant masses of the photon and fermion pairs is calculated in the leading logarithmic approximation. It is shown…
Due to the high anticipated experimental precision at the Future Circular Collider FCC-ee (or other proposed $e^+e^-$ colliders, such as ILC, CLIC, or CEPC) for electroweak and Higgs-boson precision measurements, theoretical uncertainties…
This paper presents the high-precision theoretical predictions for $e^+e^- \to l^-l^+$ scattering. Calculations are performed using the {\tt SANC} system. They take into account complete one-loop electroweak radiative corrections as well as…
An improved efficient method of calculating the hard bremsstrahlung correction to e^+ e^- -> 4f for non-zero fermion masses is presented. The non-vanishing fermion masses allow us to perform the phase space integrations to the very…
Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the Z-boson couplings to the first-generation quarks could reveal potential discrepancies between the…
The precise measurement of physics observables and the test of their consistency within the standard model (SM) are an invaluable approach, complemented by direct searches for new particles, to determine the existence of physics beyond the…
The very high luminosity run foreseen at the $Z$-pole for the FCC-ee will allow the detection in $Z$ decays of new particles with very low couplings to the Standard Model. These particles can have measurable flight paths before they decay.…
We consider large-angle two photon production in $e^+ e^-$ annihilation as a possible process to monitor the luminosity of a future $e^+ e^-$ circular collider (FCC-ee). We review and assess the status of the theoretical accuracy by…
We derive a dynamical mean-field theory for mixtures of interacting bosons and fermions on a lattice (BF-DMFT). The BF-DMFT is a comprehensive, thermodynamically consistent framework for the theoretical investigation of Bose-Fermi mixtures…
The CERN proposed $e^+e^-$ Future Circular Collider (FCC-ee) is an electroweak, flavour, Higgs and top factory with unprecedented luminosities. Many measurements at the FCC-ee will rely on precisely determining the particle production…
Important analyses at a future linear collider, including top-quark and W-boson mass measurements will depend upon the precise determination of the luminosity spectrum. This can be done, in principle,in the planned detectors. We review the…
The measurement of the charge asymmetry $A_{FB}(e^-e^+\to \mu^-\mu^+)$ will play an important role at the high-luminosity circular electron-positron collider FCCee considered for construction at CERN. In particular, near the Z resonance,…
A search is presented for resonances decaying to a Z boson and a photon. The analysis is based on data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$, and…
We study a mixture of ultracold spin-half fermionic and spin-one bosonic atoms in a shallow optical lattice where the bosons are coupled to the fermions via both density-density and spin-spin interactions. We consider the parameter regime…
We discuss possibility to detect spin 0, 1 and 1/2 dark matter (DM) at future $e^{+} e^{-}$ colliders. The models considered here are simple, consistent and renormalizable field theories, that provide correct DM abundance and satisfy direct…
We discuss contact-interaction searches in the processes e^+e^-\to \mu^+\mu^-, b\bar{b} and c\bar{c} at an e^+e^- Linear Collider with c.m. energy \sqrt{s}=0.5 TeV and with longitudinally polarized beams. The measurement of polarized cross…
The investigation of W-pair production offers unique precision tests of the electroweak theory at future e+e- colliders, including precise determinations of cross sections, the W-boson mass, and gauge-boson self-couplings. The…
We consider the capability of a future high energy $e^+ e^-$ collider to search for the $Z^\prime$ bosons associated with a $U(1)^\prime$ gauge extension of the Standard Model. Even for $Z^\prime$ masses well above the center of mass energy…
Interactions in an ultracold boson-fermion mixture are often manifested by elastic collisions. In a mixture of a condensed Bose gas (BEC) and spin polarized degenerate Fermi gas (DFG), fermions can mediate spin-spin interactions between…
The efficiency of colliders for physics is largely determined by their luminosity, while most of the energy consumed by high-energy $e^+e^-$ colliders is proportional to the total beam current. Thus, the energy efficiency is mainly…