arXiv subjects

Eremey Valetov

Publications and source records attributed to Eremey Valetov.

7 recordsLinked to original sources

arXiv2026

Three-Dimensional Simulation of the University of Hawai`i FEL Oscillator with Cavity Desynchronization

In this paper, we present three-dimensional, time-dependent simulations of the University of Hawai`i (UH) at Mānoa free-electron laser (FEL) oscillator. Using beam parameters from the UH facility, we study the pass-by-pass evolution of the radiation field, including its temporal, spectral, and transverse properties. At nominal bunch length, the radiation pulse develops temporal spiking near saturation, together with sideband formation and increased sensitivity to machine timing jitter. Our results show that modest cavity desynchronization can enhance the radiation energy by 63%. Large cavity desynchronization, on the other hand, can effectively suppress the spiking instabilities and improve robustness to timing fluctuations. Finally, we simulate a short-bunch operational mode with a bunch length comparable to the slippage length, which accelerates saturation and further amplifies the FEL power. Overall, these results provide a quantitative foundation for pulse control studies in the UH FEL oscillator and a critical benchmark for future experimental validation and machine optimization.

physics.acc-ph↗

arXiv2026

Analytic Derivation of Vertical Chromaticity in the Fermilab Muon $g{-}2$ Storage Ring

We derive the vertical chromaticity $ξ_y$ of the Fermilab Muon g-2 storage ring in closed analytic form. Expanding the Hamiltonian as a Taylor polynomial in the dynamical variables and integrating the equations of motion order by order, we obtain the vertical second-order aberrations of the homogeneous magnetic dipole ($\mathtt{DI}$) and the combined-function dipole-and-electrostatic-quadrupole element ($\mathtt{DIQ}$) used in the muon $g{-}2$ ring. Composing the per-element maps over the periodic dispersion orbit yields a closed-form expression for the vertical chromaticity $\xichromy$ of the continuous-ring $\mathtt{DIQ360}$ model, in direct functional analogy with the horizontal result of our earlier work on the same ring (Ref.~\refcite{ChromCPO11}). Comparison against COSY INFINITY differential-algebra computation shows agreement at the $10^{-11}$ level across all three ring models ($\mathtt{DIQ360}$ closed form and the modular $\mathtt{DIEQ\_ON}$, $\mathtt{DIEQ}$ via per-element composition) for muon $g{-}2$ electrostatic-quadrupole (ESQ) voltages $\Vesq \in [10, 26]\,\mathrm{kV}$.

physics.acc-ph↗

arXiv2020

Toward the Frontiers of Particle Physics With the Muon $g\textrm{-}2$ Experiment

The Muon $g\textrm{-}2$ Experiment (E989) at Fermilab has a goal of measuring the muon anomaly ($a_μ$) with unprecedented precision using positive muons. This measurement is motivated by the difference between the previous Brookhaven $a_μ$ measurement and Standard Model prediction exceeding three standard deviations, which hints at the possibility of physics beyond the Standard Model. Muons are circulated in a storage ring, and the measurement requires a precise determination of the muon anomalous precession frequency (spin precession relative to momentum) from the resulting decay positron time and energy measurements collected with calorimeters. The average magnetic field seen by the muons needs to be known with high precision, and so the storage ring magnetic field is shimmed to be very uniform and is continually monitored with nuclear magnetic resonance (NMR) probes. Detailed Muon Campus beamline and muon storage ring simulations are also required for quantifying beam dynamics and spin-related systematic effects in the determination of the muon anomalous precession frequency, e.g. muon losses during the measurement window. At the time of the conference, the experiment has recently commenced Run-3, and the release of Run-1 physics results is planned for 2020.

physics.acc-ph↗

arXiv2020

Bases of Quantum Group Algebras in Terms of Lyndon Words

We have reviewed some results on quantized shuffling, and in particular, the grading and structure of this algebra. In parallel, we have summarized certain details about classical shuffle algebras, including Lyndon words (primes) and the construction of bases of classical shuffle algebras in terms of Lyndon words. We have explained how to adapt this theory to the construction of bases of quantum group algebras in terms of Lyndon words. This method has a limited application to the specific case of the quantum group parameter being a root of unity, with the requirement that specialization to the root of unity is non-restricted. As an additional, applied part of this work, we have implemented a Wolfram Mathematica package with functions for quantum shuffle multiplication and constructions of bases in terms of Lyndon words.

math.QA↗

arXiv2020

Spin Dynamics Investigation of Quasi-Frozen Spin Lattice for EDM Searches

The Quasi-Frozen Spin (QFS) method was proposed by Yu. Senichev et al. in [1] as an alternative to the Frozen Spin (FS) method [2] for the search of deuteron electric dipole moment (dEDM). The QFS approach simplifies the design of the lattice. In particular, small changes to the currently operating COSY storage ring will satisfy the QFS condition. Spin decoherence and systematic errors fundamentally limit EDM signal detection and measurement. Our QFS implementation method includes measurement of spin precession in (1) the horizontal plane to calibrate the magnetic field when changing field polarity and (2) the vertical plane to search for EDM. To address systematic errors due to element misalignments, we track particle bunches in forward and reverse directions. We modeled and tracked two QFS and one FS lattice in COSY INFINITY. The models include normally distributed random variate spin kicks in magnetic dipoles and combined electrostatic and magnetic field elements. We used Wolfram Mathematica programs to partially automate lattice input file generation and tracking output data analysis. We observed indications that the QFS method is a viable alternative to the FS method. [1] Y. Senichev, A. Lehrach, B. Lorentz, R. Maier, S. Andrianov, A. Ivanov, S. Chekmenev, M. Berz, and E. Valetov (on behalf of the JEDI Collaboration), in Proceedings of IPAC 2015, Richmond, VA (2015) MOPWA044. [2] D. Anastassopoulos et al., AGS Proposal: Search for a Permanent Electric Dipole Moment of the Deuteron Nucleus at the $10^{-29}\:e\cdot\mathrm{cm}$ Level, BNL Report, Brookhaven National Laboratory, Upton, NY (2008).

physics.acc-ph↗

arXiv2018

Direct Calculation of the Transfer Map of Electrostatic Deflectors, and Comparison with the Codes COSY INFINITY and GIOS

COSY INFINITY uses a beamline coordinate system with a Frenet-Serret frame relative to the reference particle, and calculates differential algebra-valued transfer maps by integrating the ODEs of motion in the respective vector space over a differential algebra (DA). We will describe and perform computation of the DA transfer map of an electrostatic spherical deflector in a laboratory coordinate system using two conventional methods: (1) by integrating the ODEs of motion using a 4th order Runge-Kutta integrator and (2) by computing analytically and in closed form the properties of the respective elliptical orbits from Kepler theory. We will compare the resulting transfer maps with (3) the DA transfer map of COSY INFINITY's built-in electrostatic spherical deflector element ESP and (4) the transfer map of the electrostatic spherical deflector computed using the program GIOS. In addition to the electrostatic spherical deflector, we study an electrostatic cylindrical deflector, where the Kepler theory is not applicable. We compute the DA transfer map by the ODE integration method (1), and compare it with the transfer maps by (3) COSY INFINITY's built-in electrostatic cylindrical deflector element ECL, and (4) GIOS. In addition to the code listings in the appendices, the codes to run the test cases are available at http://bt.pa.msu.edu/cgi-bin/display.pl?name=ELSPHTM17

physics.acc-ph↗

arXiv2017

Frequency domain method of the search for the deuteron electric dipole moment in a storage ring with imperfections

The method is based on four fundamental features. The total spin precession frequency in the vertical plane due to the electric and magnetic dipole moments in an imperfect ring in a vertical plane is measured. The position of the ring elements is unchanged from clockwise to counter-clockwise operation. The calibration of the effective Lorentz factor using the polarization precession frequency measurement in the horizontal plane is carried out alternately in each CW and CCW operation. And the approximate relationship between the frequencies of the polarization precession in different planes is set to exclude them from mixing to the vertical frequency of the expected EDM signal at a sensitivity level approaching $10^{-29}$ $e\cdot cm$.

physics.acc-ph↗