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ThesisItem Open Access Higher order contributions to electron-acoustic solitary waves featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Sharma, Anjali; Parveen BalaIn this thesis, a homogeneous system of unmagnetized and collisionless plasma constituting of cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to obey hybrid Cairns-Tsallis distribution. This distribution is applicable within the range and .Using standard Reductive Perturbation Method (RPM), dispersion relation and Korteweg de-Vries (KdV) equation has been derived. Reductive preturbation method is further extended to include the contribution of higher order terms. Renormalization method is employed in studying the propagation of electron acoustic solitary waves as well as higher order solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter( ), hot-to-cold electron density ratio( ), hot-to-cold electron temperature ratio( ), Mach number( ) and nonextensive parameter( ). Only negative potential structures are reported in our plasma model. The numerical results reflects that on taking the higher order correction terms into account, the amplitude of the dressed soliton solution increases however its width narrows. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Higher order contributions to electron-acoustic solitary waves featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Sharma, Anjali; Bala, ParveenIn this thesis, a homogeneous system of unmagnetized and collisionless plasma constituting of cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to obey hybrid Cairns-Tsallis distribution. This distribution is applicable within the range and .Using standard Reductive Perturbation Method (RPM), dispersion relation and Korteweg de-Vries (KdV) equation has been derived. Reductive preturbation method is further extended to include the contribution of higher order terms. Renormalization method is employed in studying the propagation of electron acoustic solitary waves as well as higher order solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter( ), hot-to-cold electron density ratio( ), hot-to-cold electron temperature ratio( ), Mach number( ) and nonextensive parameter( ). Only negative potential structures are reported in our plasma model. The numerical results reflects that on taking the higher order correction terms into account, the amplitude of the dressed soliton solution increases however its width narrows. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Cylindrical electron-acoustic solitary waves with hybrid Cairns-Tsallis distributed hot electrons(Punjab Agricultural University, Ludhiana, 2019) Harmanpreet Kaur; Parveen BalaThe propagation of cylindrical electron acoustic solitary waves in a plasma system constituting cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to follow hybrid nonthermal-nonextensive distribution popularly known as Cairns-Tsallis distribution. This distribution is applicable within the parameters range 0.6 q 1 and 0 0.25. Using Reductive preturbation method Korteweg de- Vries (KdV) is derived to obtain the required solution for cylindrical electron acoustic solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter ( ) , hot-to-cold electron density ratio ( ) and nonextensive parameter ( q ). Only negative potential structures are reported in our plasma model. The effect of nonextensivity (q), nonthermality ( ) and cylindrical geometry on the amplitudes and width of electron acoustic potential structures have been studied numerically. The numerical results are presented in the form of graphs in given parametric ranges. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Electron-acoustic double layers featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Arshpreet Kaur; Parveen BalaPlasma is an ionized gas that can be considered as collection of positive and negative charge carriers and has net zero charge. It exihibits various striking nonlinear structures such as solitons and double layers. The nonlinear dynamics of large amplitude electron acoustic double layers in an unmagnetized collisionless plasma consisting of cold and hot electrons has been studied. The electrons are assumed to follows the cairns-tsallis distribution. Sagdeev pseudopotential method has been used to investigate the occurance of large amplitude double layers, focusing on how their characteristics depends upon the different parameters. For the selected range of parameters, it is found that only compressive double layers can exist. Further, the analysis is extended for small amplitude double layer solution by expanding the Sagdeev potential in the weakly coupled plasma limit ( <<1). The upper limits of the Mach number for the existence of double layer are dertermined, and their values are significantly modified in the presence of Cairns-Tsallis distributed electrons. Polarity of the nonlinear structures strongly depends on the nonthermal parameter ( ) and nonextensivity (q) of electrons. Depending on the nature of these double layers, their associated electric fields are thought to be responsible for particle acceleration or deceleration.ThesisItem Open Access Effect of adulteration on dielectric properties and electrical conductivity of honey(Punjab Agricultural University, Ludhiana, 2019) Zorawar Singh; Paramjit SinNon-destructive techniques for determining the adulteration of food products are rapidly gaining a wide scientific interest, partly due to their utilization in the industrial sector. One of the important non-destructive techniques is the measurement of dielectric properties and electrical conductivity. Under this technique, the substance under study is subject to an alternating electric field and a rapid energy gaining and losing process starts due to molecular alignments. This process can be characterized by two parameters; dielectric constant and loss tangent. Also, electrical conductivity measures the charge carrying capacity of the substance. The present study aims to evaluate the effect of adulteration of honey, with sugar syrup, on the dielectric properties and electrical conductivity. These properties were studied at five different frequencies (10, 30, 50, 70, and 100 kHz) and seven different temperatures (20, 30, 40, 50, 60, 70, and 80 °C) for pure honey, sucrose syrup and five different concentrations of sugar syrup in honey (10, 20, 30, 40, and 50%). Dielectric properties decreased with increasing frequency. Meanwhile, dielectric constant decreased and loss tangent increased with temperature. Both parameters decreased in a linear fashion with the addition of sugar syrup. The adulteration of honey has a significant effect on its dielectric properties for impurity levels above 10% and temperatures below 50 °C. Electrical conductivity increased linearly with temperature and sugar syrup impurity level, while the frequency has negligible effect on it. Further, the statistical analysis showed that the effect of adulteration of honey on its electrical conductivity is significant at temperatures above 50 °C and for impurity levels above 20%.ThesisItem Open Access Control sample studies for rare radiative decay using Belle detector(Punjab Agricultural University, Ludhiana, 2019) Amritpal Singh; Sharma, Rajeev KumarWe study the decay modes of B mesons to final states including J/ψ and mesons based on a large amount of data sample at the ϒ(4S) state collected with Belle detector in KEKB asymmetric energy collider.
