arXiv subjects

Mikhail G. Kozlov

Publications and source records attributed to Mikhail G. Kozlov.

25 records · Page 2Linked to original sources

arXiv2019

Next to leading order QED corrections to the process $ γγ\rightarrowμ^+μ^-γ$

We have calculated one loop quantum electrodynamic corrections to the process $ γγ\rightarrowμ^+μ^-γ$, where all photons are on mass shell and the muon mass is taken into account. The result is obtained in the analytical form and is implemented as functions in the C programming language, which can be used to calculate the cross-section, the differential cross section, and to construct generators. We also present numerical results for corrections to the cross section and to the differential cross section.

hep-ph↗

arXiv2018

High magnetic fields for fundamental physics

Various fundamental-physics experiments such as measurement of the birefringence of the vacuum, searches for ultralight dark matter (e.g., axions), and precision spectroscopy of complex systems (including exotic atoms containing antimatter constituents) are enabled by high-field magnets. We give an overview of current and future experiments and discuss the state-of-the-art DC- and pulsed-magnet technologies and prospects for future developments.

physics.ins-det↗

arXiv2018

Constraints on exotic spin-dependent interactions between matter and antimatter from antiprotonic helium spectroscopy

Heretofore undiscovered spin-0 or spin-1 bosons can mediate exotic spin-dependent interactions between standard-model particles. Here we carry out the first search for semileptonic spin-dependent interactions between matter and antimatter. We compare theoretical calculations and spectroscopic measurements of the hyperfine structure of antiprotonic helium to constrain exotic spin- and velocity-dependent interactions between electrons and antiprotons.

physics.atom-ph↗

arXiv2017

Measuring molecular parity nonconservation using nuclear magnetic resonance spectroscopy

The weak interaction does not conserve parity and therefore induces energy shifts in chiral enantiomers that should in principle be detectable in molecular spectra. Unfortunately, the magnitude of the expected shifts are small and in spectra of a mixture of enantiomers, the energy shifts are not resolvable. We propose a nuclear magnetic resonance (NMR) experiment in which we titrate the chirality (enantiomeric excess) of a solvent and measure the diasteriomeric splitting in the spectra of a chiral solute in order to search for an anomalous offset due to parity nonconservation (PNC). We present a proof-of-principle experiment in which we search for PNC in the \textsuperscript{13}C resonances of small molecules, and use the \textsuperscript{1}H resonances, which are insensitive to PNC, as an internal reference. We set a new constraint on molecular PNC in \textsuperscript{13}C chemical shifts at a level of $10^{-5}$\,ppm, and provide a discussion of important considerations in the search for molecular PNC using NMR spectroscopy.

physics.chem-ph↗

arXiv2016

One-loop pentagon integral with one offshell leg in $d$ dimensions from differential equations in $ε$-form

We apply differential equations technique to the calculation of the one-loop massless diagram with one offshell legs. Using reduction to $ε$-form, we managed to obtain a simple one-fold integral representation exact in space-time dimensionality. Expansion of the obtained result in $ε$ and analytical continuation to physical region are discussed.

hep-ph↗

arXiv2015

One-loop pentagon integral in $d$ dimensions from differential equations in $ε$-form

We apply the differential equation technique to the calculation of the one-loop massless diagram with five onshell legs. Using the reduction to $ε$-form, we manage to obtain a simple one-fold integral representation exact in space-time dimensionality. The expansion of the obtained result in $ε$ and the analytical continuation to physical regions are discussed.

hep-ph↗

arXiv2012

Sensitivity to a possible variation of the Proton-to-Electron Mass Ratio of Torsion-Wagging-Rotation Transitions in Methylamine (CH3NH2)

We determine the sensitivity to a possible variation of the proton-to-electron mass ratio μfor torsion-wagging-rotation transitions in the ground state of methylamine (CH3NH2). Our calculation uses an effective Hamiltonian based on a high-barrier tunneling formalism combined with extended-group ideas. The μ-dependence of the molecular parameters that are used in this model are derived and the most important ones of these are validated using the spectroscopic data of different isotopologues of methylamine. We find a significant enhancement of the sensitivity coefficients due to energy cancellations between internal rotational, overall rotational and inversion energy splittings. The sensitivity coefficients of the different transitions range from -19 to +24. The sensitivity coefficients of the 78.135, 79.008, and 89.956 GHz transitions that were recently observed in the disk of a z = 0.89 spiral galaxy located in front of the quasar PKS 1830-211 [S. Muller et al. Astron. Astrophys. 535, A103 (2011)] were calculated to be -0.87 for the first two and -1.4 for the third transition, respectively. From these transitions a preliminary upper limit for a variation of the proton to electron mass ratio of Δμ/μ< 9 x 10^{-6} is deduced.

physics.chem-ph↗