arXiv subjects

Z. E. Musielak

Publications and source records attributed to Z. E. Musielak.

At least 37 records · Page 2Linked to original sources

arXiv2021

Bateman Oscillators: Caldirola-Kanai and Null Lagrangians and Gauge Functions

The Lagrange formalism is developed for Bateman oscillators, which include both damped and amplified systems, and a novel method to derive the Caldirola-Kanai and null Lagrangians is presented. For the null Lagrangians, corresponding gauge functions are obtained. It is shown that the gauge functions can be used to convert the undriven Bateman oscillators into the driven ones. Applications of the obtained results to quantizatation of the Bateman oscillators are briefly discussed.

physics.class-ph↗

arXiv2021

Chiral Bargmann-Wigner Equations for Spin-1 Massive Fields

The Bargman-Wigner equations are generalized to include chiral symmetry based on the irreps of the Poincaré group, and the chirial Bargmann-Wigner equations are derived for spin-1 massive fields. By specifying the chiral basis, the chiral Bargmann-Wigner equations are reduced to the Proca-like equation, which is coupled by chirality to an auxiliary equation for spin-0 massive field. The coupling is a new phenomenon whose physical implications for the Higgs field and dark matter are discussed.

physics.gen-ph↗

arXiv2021

New Equation of Nonrelativistic Physics and Theory of Dark Matter

Two infinite sets of Galilean invariant equations are derived using the irreducible representations of the orthochrous extended Galilean group. It is shown that one set contains the Schrödinger equation, which is the fundamental equation for ordinary matter, and the other set has a new asymmetric equation, which is proposed to be the fundamental equation for dark matter. Using this new equation, a theory of dark matter is developed and its profound physical implications are discussed. This theory explains the currently known properties of dark matter and also predicts a detectable gravitational radiation.

physics.gen-ph↗

arXiv2020

Chiral Symmetry in Dirac Equation and its Effects on Neutrino Masses and Dark Matter

Chiral symmetry is included into the Dirac equation using the irreducible representations of the Poincaré group. The symmetry introduces the chiral angle that specifies the chiral basis. It is shown that the correct identification of these basis allows explaining small masses of neutrinos and predicting a new candidate for Dark Matter massive particle.

physics.gen-ph↗

arXiv2020

Gauge Functions in Classical Mechanics: From Undriven to Driven Dynamical Systems

Novel gauge functions are introduced to non-relativistic classical mechanics and used to define forces. The obtained results show that the gauge functions directly affect the energy function and that they allow converting an undriven physical system into a driven one. This is a novel phenomenon in dynamics that resembles the role of gauges in quantum field theories.

math-ph↗

arXiv2020

Null Lagrangians and Invariance of Action: Exact Gauge Functions

Null Lagrangians and their gauge functions are derived for given standard and non-standard Lagrangians. The obtained standard null Lagrangians generalize those previously found but the non-standard null Lagrangians are new. The gauge functions are used to make the action invariant and introduce the exact null Lagrangians, which form a new family of null Lagrangians. The conditions required for the action to be invariant are derived for all null Lagrangians presented in this paper, thus, making them exact. As a specific application, the exact null Lagrangians are derived for a second-order ordinary differential equation. The application shows that the exact null Lagrangians can be obtained for any ordinary differential equation with known Lagrangian.

math-ph↗

arXiv2020

New Cutoff Frequency for Torsional Alfv'en Waves Propagating along Wide Solar Magnetic flux Tubes

An isolated, isothermal, and wide magnetic flux tube embedded either in the solar chromosphere or in the lower solar corona is considered, and the propagation of linear torsional Alfv'en waves is investigated. It is shown that the wideness of the tube leads to a new cutoff frequency, which is a local quantity that gives the conditions for the wave propagation at different atmospheric heights. The cutoff is used to establish the ranges of frequencies for the propagating and reflected waves in the solar chromosphere and lower solar corona. The obtained results are compared to those previously obtained for thin magnetic flux tubes and the differences are discussed. Moreover, the results are also compared to some current observational data, and used to establish the presence of propagating waves in the data at different atmospheric heights; this has profound implications on the energy and momentum transfer by the waves in the solar atmosphere, and the role of linear torsional Alfv'en waves in the atmospheric heating and wind acceleration.

astro-ph.SR↗

arXiv2020

Gauge Functions and Galilean Invariance of Lagrangians

A novel method to make Lagrangians Galilean invariant is developed. The method, based on null Lagrangians and their gauge functions, is used to demonstrate the Galilean invariance of the Lagrangian for Newton's law of inertia. It is suggested that this new solution of an old physics problem may have implications and potential applications to all gauge-based theories of physics.

math-ph↗

arXiv2018

Vertical Propagation of Acoustic Waves in the Solar Inter-Network as Observed by IRIS

We investigate the Interface Region Imaging Spectrograph (IRIS) observations of the quiet-Sun (QS) to understand the propagation of acoustic waves in transition region (TR) from photosphere. We selected a few IRIS spectral lines, which include the photospheric (Mn~{\sc i} 2801.25~Å), chromospheric (Mg~{\sc ii} k 2796.35~Å) and TR (C~{\sc ii} 1334.53~Å), to investigate the acoustic wave propagation.The wavelet cross-spectrum reveals significant coherence (about 70\% locations) between photosphere and chromosphere. Few minutes oscillations (i.e., period range from 1.6 to 4.0 minutes) successfully propagate into chromosphere from photosphere, which is confirmed by dominance of positive phase lags. However, in higher period regime (i.e., greater than $\approx$ 4.5 minutes), the downward propagation dominates is evident by negative phase lags. The broad spectrum of waves (i.e., 2.5-6.0 minutes) propagates freely upwards from chromosphere to TR. We find that only about 45\% locations (out of 70\%) show correlation between chromosphere and TR. Our results indicate that roots of 3 minutes oscillations observed within chromosphere/TR are located in photosphere. Observations also demonstrate that 5 minute oscillations propagate downward from chromosphere. \textbf{However, some locations within QS also show successful propagation of 5 minute oscillations as revealed by positive phase lags, which might be the result of magnetic field}. In addition, our results clearly show that a significant power, within period ranging from 2.5 to 6.0 minutes, of solar chromosphere is freely transmitted into TR triggering atmospheric oscillations. Theoretical implications of our observational results are discussed.

astro-ph.SR↗

arXiv2017

Dynamics of a Probable Earth-mass Planet in GJ 832 System

Stability of planetary orbits around the GJ 832 star system, which contains inner (GJ 832c) and outer (GJ 832b) planets, is investigated numerically and a detailed phase-space analysis is performed. A special emphasis is given to the existence of stable orbits for a planet less than 15M$_\oplus$ which is injected between the inner and outer planets. Thus, numerical simulations are performed for three and four bodies in elliptical orbits (or circular for special cases) by using a large number of initial conditions that cover the selected phase-spaces of the planet's orbital parameters. The results presented in the phase-space maps for GJ 832c indicate the least deviation of eccentricity from its nominal value, which is then used to determine its inclination regime relative to the star-outer planet plane. Also, the injected planet displays stable orbital configurations for at least one billion years. Then, the radial velocity curves based on the signature from the Keplerian motion are generated for the injected planets with masses 1M$_\oplus$ to 15M$_\oplus$ in order to estimate their semimajor axes and mass-limit. The synthetic RV signal suggests that an additional planet of mass $\le$ 15M$_\oplus$ with dynamically stable configuration may be residing between 0.25 - 2.0 AU from the star. We have provided an estimated number of RV observations for the additional planet that is required for further observational verification.

astro-ph.EP↗

arXiv2017

Numerical Simulations of Torsional Alfvén Waves in Axisymmetric Solar Magnetic Flux Tubes

We investigate numerically Alfvén waves propagating along an axisymmetric and non-isothermal solar flux tube embedded in the solar atmosphere. The tube magnetic field is current-free and diverges with height, and the waves are excited by a periodic driver along the tube magnetic field lines. The main results are that the two wave variables, the velocity and magnetic field perturbations in the azimuthal direction, behave differently as a result of gradients of physical parameters along the tube. To explain these differences in the wave behavior, the time evolution of the wave variables and the resulting cutoff period for each wave variable are calculated, and used to determine regions in the solar chromosphere where strong wave reflection may occur.

astro-ph.SR↗

arXiv2016

Variation of acoustic cutoff period with height in the solar atmosphere: theory versus observations

Recently Wiśniewska et al. demonstrated observationally how the acoustic cutoff frequency varies with height in the solar atmosphere including the upper photosphere and the lower and middle chromosphere, and showed that the observational results cannot be accounted for by the existing theoretical formulas for the acoustic cutoff. In order to reproduce the observed variation of the cutoff with atmospheric height, numerical simulations of impulsively generated acoustic waves in the solar atmosphere are performed, and the spectral analysis of temporal wave profiles is used to compute numerically changes of the acoustic cutoff with height. Comparison of the numerical results with the observational data shows good agreement, which clearly indicates that the obtained results may be used to determine the structure of the background solar atmosphere.

astro-ph.SR↗

arXiv2016

On the radio detection of multiple-exomoon systems due to plasma torus sharing

The idea of single exomoon detection due to the radio emissions caused by its interaction with the host exoplanet is extended to multiple-exomoon systems. The characteristic radio emissions are made possible in part by plasma from the exomoons own ionosphere (Noyola et. al. 2014). In this work, it is demonstrated that neighboring exomoons and the exoplanetary magnetosphere could also provide enough plasma to generate a detectable signal. In particular, the plasma-torus-sharing phenomenon is found to be particularly well suited to facilitate the radio detection of plasma-deficient exomoons. The efficiency of this process is evaluated, and the predicted power and frequency of the resulting radio signals are presented.

astro-ph.EP↗

arXiv2015

The three-body problem

The three-body problem, which describes three masses interacting through Newtonian gravity without any restrictions imposed on the initial positions and velocities of these masses, has attracted the attention of many scientists for more than 300 years. In this paper, we present a review of the three-body problem in the context of both historical and modern developments. We describe the general and restricted (circular and elliptic) three-body problems, different analytical and numerical methods of finding solutions, methods for performing stability analysis, search for periodic orbits and resonances, and application of the results to some interesting astronomical and space dynamical settings. We also provide a brief presentation of the general and restricted relativistic three-body problems, and discuss their astronomical applications.

astro-ph.EP↗

arXiv2015

Numerical simulations of multi-shell plasma twisters in the solar atmosphere

We perform numerical simulations of impulsively generated Alfvén waves in an isolated photospheric flux tube, and explore the propagation of these waves along such magnetic structure that extends from the photosphere, where these waves are triggered, to the solar corona, and analyze resulting magnetic shells. Our model of the solar atmosphere is constructed by adopting the temperature distribution based on the semi-empirical model and specifying the curved magnetic field lines that constitute the magnetic flux tube which is rooted in the solar photosphere. The evolution of the solar atmosphere is described by 3D, ideal magnetohydrodynamic equations that are numerically solved by the FLASH code. Our numerical simulations reveal, based on the physical properties of the multi-shell magnetic twisters and the amount of energy and momentum associated with them, that these multi-shell magnetic twisters may be responsible for the observed heating of the lower solar corona and for the formation of solar wind. Moreover, it is likely that the existence of these twisters can be verified by high-resolution observations.

astro-ph.SR↗

arXiv2015

Torsional Alfven Waves in Solar Magnetic Flux Tubes of Axial Symmetry

Aims: Propagation and energy transfer of torsional Alfvén waves in solar magnetic flux tubes of axial symmetry is studied. Methods: An analytical model of a solar magnetic flux tube of axial symmetry is developed by specifying a magnetic flux and deriving general analytical formulae for the equilibrium mass density and a gas pressure. The main advantage of this model is that it can be easily adopted to any axisymmetric magnetic structure. The model is used to simulate numerically the propagation of nonlinear Alfvén waves in such 2D flux tubes of axial symmetry embedded in the solar atmosphere. The waves are excited by a localized pulse in the azimuthal component of velocity and launched at the top of the solar photosphere, and they propagate through the solar chromosphere, transition region, and into the solar corona. Results: The results of our numerical simulations reveal a complex scenario of twisted magnetic field lines and flows associated with torsional Alfvén waves as well as energy transfer to the magnetoacoustic waves that are triggered by the Alfvén waves and are akin to the vertical jet flows. Alfvén waves experience about 5 % amplitude reflection at the transition region. Magnetic (velocity) field perturbations experience attenuation (growth) with height is agreement with analytical findings. Kinetic energy of magnetoacoustic waves consists of 25 % of the total energy of Alfvén waves. The energy transfer may lead to localized mass transport in the form of vertical jets, as well as to localized heating as slow magnetoacoustic waves are prone to dissipation in the inner corona.

astro-ph.SR↗

arXiv2014

Numerical simulations of impulsively generated Alfvén waves in solar magnetic arcades

We perform numerical simulations of impulsively generated Alfvén waves in an isolated solar arcade, which is gravitationally stratified and magnetically confined. We study numerically the propagation of Alfvén waves along such magnetic structure that extends from the lower chromosphere, where the waves are generated, to the solar corona, and analyze influence of the arcade size and width of the initial pulses on the wave propagation and reflection. Our model of the solar atmosphere is constructed by adopting the temperature distribution based on the semi-empirical VAL-C model and specifying the curved magnetic field lines that constitute the asymmetric magnetic arcade. The propagation and reflection of Alfvén waves in this arcade is described by 2.5D magnetohydrodynamic equations that are numerically solved by the FLASH code. Our numerical simulations reveal that the Alfvén wave amplitude decreases as a result of a partial reflection of Alfvén waves in the solar transition region, and that the waves which are not reflected leak through the transition region and reach the solar corona. We also find the decrement of the attenuation time of Alfvén waves for wider initial pulses. Moreover, our results show that the propagation of Alfvén waves in the arcade is affected by spatial dependence of the Alfvén speed, which leads to phase-mixing that is stronger for more curved and larger magnetic arcades. We discuss processes that affect the Alfvén wave propagation in an asymmetric solar arcade and conclude that besides phase-mixing in the magnetic field configuration, plasma properties of the arcade and size of the initial pulse as well as structure of the solar transition region all play a vital role in the Alfvén wave propagation.

astro-ph.SR↗

arXiv2014

Fast Magnetic Twister and Plasma Perturbations in a 3-D Coronal Arcade

We present results of 3-D numerical simulations of a fast magnetic twister excited above a foot-point of the potential solar coronal arcade that is embedded in the solar atmosphere with the initial VAL-IIIC temperature profile, which is smoothly extended into the solar corona. With the use of the FLASH code, we solve 3-D ideal magnetohydrodynamic equations by specifying a twist in the azimuthal component of magnetic field in the solar chromosphere. The imposed perturbation generates torsional Alfvén waves as well as plasma swirls that reach the other foot-point of the arcade and partially reflect back from the transition region. The two vortex channels are evident in the generated twisted flux-tube with a fragmentation near its apex that results from the initial twist as well as from the morphology of the tube. The numerical results are compared to observational data of plasma motions in a solar prominence. The comparison shows that the numerical results and the data qualitatively agree even though the observed plasma motions occur over comparatively large spatio-temporal scales in the prominence.

astro-ph.SR↗