The analytical calculation of Feynman integrals is an important problem in modern quantum field theory. This task is important both for obtaining the most accurate predictions for observable quantities and for some areas of pure mathematics such as theory of periods in algebraic geometry. Nevertheless, it is not always possible to obtain analytical solutions for all Feynman integrals beyond...
This work provides a detailed description of the method for the first direct measurement of all Michel parameters in the $\tau^- \to \mu^- \bar{\nu}_\mu\nu_\tau$ decay related to the polarization of the daughter muon. An application of the suggested method in the existing and future experiments at $e^+e^-$ colliders is considered. We have performed a feasibility study for the future Super...
The work is devoted to the study of canonical formalism for one of the General Relativity modifications, the embedding theory. It is known that the embedding theory can be rewritten as General Relativity with an additional contribution of matter, which is called the embedding matter. The canonical description of such embedding theory is interesting for a better understanding of the embedding...
We propose dual representation for the massless spin 2 theory by the third-rank tensor field with the hook Young diagram. We start from the linearized system of Einstein equations which includes Nordström equation. Once the linearized Nordström equation is a topological field theory, the general solution is a pure gauge. Substituting this general solution into the rest of Einstein system, we...
The recent CMS results on flavor physics will be discussed, in particular, the full Run-2 study of dimuon decays of B0 and B0s mesons.
We consider a gauge theory of vector fields in 3D Minkowski space. At the free level, the dynamical variables are subjected to the extended Chern–Simons (ECS) equations with higher derivatives. If the color index takes n values, the third-order model admits a 2n-parameter series of second-rank conserved tensors, which includes the canonical energy–momentum. Even though the canonical energy is...
We adapted the Appleby-Battye-Starobinsky (ABS) model of $F(R)$-gravity towards describing
double cosmological inflation and formation of primordial black holes with masses up to $10^{19}
g$ in the single-field model. Masses of primordial black holes in this model are beyond the Hawking limit $10^{15} g$, and this allows us to assert that primordial black holes can form a part of cold...
It can be shown that an arbitrary (pseudo) Riemannian manifold can be considered as a surface in a flat space of a larger number of dimensions. This approach, for example, leads to a modified theory of gravity -- the embedding theory. However, the construction of explicit embeddings in a flat space is a nontrivial task that can be reformulated as the solution of a system of nonlinear partial...
We find the gravitational chiral anomaly for spin 3/2 fields in the framework of the new theory proposed by S. L. Adler. This anomaly differs by -19 times from the anomaly for Dirac field. Adler's theory includes Rarita-Schwinger fields and an additional field with spin 1/2, interaction with which allows solving the well-known problem with the construction of a quantum-field perturbation theory.
We study the six-dimensional ${\cal N=(1,0)}$ supersymmetric model of
interacting gauge multiplet and hypermultiplet with arbitrary
self-coupling. Using the background field method in the harmonic
superspace, we calculate the divergent part of the one-loop
effective action and discuss the possible finite contribution to the
low-energy effective action. We demonstrate that the...
Out-of-time ordered correlation functions (OTOCs) are widely used as a diagnostic of quantum chaos and allow one to estimate the quantum Lyapunov exponent, which reproduces classical Lyapunov exponent in the semiclassical limit. However, in most cases, OTOCs and quantum Lyapunov exponent are calculated numerically. We consider nonlinear vector mechanics with a broken $O(N)$ symmetry, which...
Nowadays the supersymmetic models are widely used to extend the Standard Model. In some realistic ones the supersymmmetry is spontaneously violated at energies of order 1 TeV. This fact is effectively described by a chiral sgoldstino multiplet consisting of a Goldstone fermion, goldstino, a scalar sgoldstino and an auxiliary field with a none-zero vev.
In the paper 2112.06083 we consider light...
The Jiangmen Underground Neutrino Observatory (JUNO) is a neutrino experiment under construction with a broad physics program. The main goals of JUNO are the determination of the neutrino mass ordering and the high precision measurement of neutrino oscillation properties. High quality reconstruction of reactor neutrino energy is crucial for the success of the experiment.
The JUNO detector is...
Measurements of the T-odd correlation in the K+ --> e^{+} nu pi^{0} gamma radiative
decay are performed at the "OKA" detector exposed to 18 GeV/c RF separated beam of
the U-70 PS. About 100K events of the decay are selected with a background of 15%.
The measured correlation ksi is a mixed product of the e^{+}, pi^{0} and gamma
momenta in the kaon rest frame, normalised to M_{K}^{3}. For the...
The gluon fusion and vector-boson-fusion Higgs boson production modes are measured using proton--proton collisions in the $H\rightarrow W W^* \rightarrow e\nu \mu\nu$ decay channel. The Large Hadron Collider delivered proton-proton collisions at a centre-of-mass energy of 13 TeV between 2015 and 2018 which were recorded by the ATLAS detector, corresponding to an integrated luminosity of 139...
Standard Model of high energy physics is very successful, but neutrino sector is not completely accommodated into it (e.g. neutrino oscillations). One of the possible solution is introduction of heavy sterile neutrino, which does not have any flavour and interacts with only flavour SM neutrinos via oscillations.
In this talk studies of heavy sterile neutrino N is presented, where neutrino...
We perform Monte Carlo simulations of the sterile neutrino signal at the fixed target experiment PS191 operated on a proton beam of 19.2GeV at CERN in the eighties. We find that the strongest bounds the PS191 could obtain are significantly lower than what they published, and now are obsolete being surpassed by recent T2K, NA62, E949, TRIUMF and PIENU experiments.
(Based on arXiv:2112.06800.)
Searches for the light invisible hypothetic pseudoscalar in the decay $K^+\rightarrow\pi^{+}\pi^{0}P$ are performed for two alternative scenarios, namely for the pseudoscalar sgoldstino and for the axion. We analysed the data taken from the "OKA" detector in 2018. The setup uses 18 GeV/c RF separated beam of the U-70 proton synchrotron.
No signal is observed, the upper limits for the branching...
Measurements of the branching ratios of conversion decays are necessary to test the vector dominance model and estimate the background in the study of quark-gluon plasma. An important source of information about the physical processes occurring in a quark-gluon plasma is the production of dileptons, in particular, the production of electron-positron pairs. In experiments, the measured number...
Mixing matrix parameters in a lepton sector are expected to be measured precisely by the next-generation experiments. One of them is an accelerator deep underground neutrino experiment DUNE, which will have a wide physics program in particular neutrino oscillations. Its main goal is to determine the neutrino mass hierarchy, the charge-parity phase $\delta_{\text{CP}}$ and the octant of mixing...
The composite Higgs model assume that the Higgs field arises as the pseudo-Goldstone mode corresponding to a dynamical symmetry breaking in a new strongly coupled sector. We present the soft-wall holographic model where such symmetry breaking occurs as a first order phase transition. In this case the bubble nucleation in the early universe becomes possible. To study the homogeneous solutions...
