Polarized Light from the Transportation of a Matter-Antimatter Beam in a Plasma

A relativistic electron-positron beam propagating through a magnetized electron-ion plasma is shown to generate both circularly and linearly polarized synchrotron radiation. The degrees of circular and linear polarizations depend both on the density ratio of pair beam to background plasma and initial magnetization, and a maximum degree of circular polarization $\langle P_\textrm{circ}\rangle \approx 18\%$ is found to occur for a tenuous pair beam. We demonstrate that the generation of circularly polarized radiation is intrinsically linked to asymmetric energy dissipation of the pair beam during the filamentation instability dynamics in the electron-ion plasma. These results can help in understanding the recent observations of circularly polarized radiation from gamma-ray-bursts

On Link Availability Probability of Routing Protocols for Urban Scenario in VANETs

This paper presents the link availability probability. We evaluate and compare the link availability probability for routing protocols; Ad hoc On-demand Distance vector (AODV), Dynamic Source Routing (DSR) and Fisheye State Routing (FSR) for different number of connections and node density. A novel contribution of this work is enhancement in existing parameters of routing protocols; AODV, DSR and FSR as MOD-AODV, MOD-DSR and MOD-FSR. From the results, we observe that MOD-DSR and DSR outperform MOD-AODV, AODV, MODOLSR and OLSR in terms of Packet Delivery Ratio (PDR), Average End-to End Delay (AE2ED), link availability probability at the cost of high value of Normalized Routing Overhead (NRO).Comment: IEEE Conference on Open Systems (ICOS2012)", Kuala Lumpur, Malaysia, 201

Nanoindentation studies on waveguides inscribed in chalcogenide glasses using ultrafast laser

Optical straight waveguides are inscribed in GeGaS and GeGaSSb glasses using a high repetition-rate sub-picosecond laser. The mechanical properties of the glasses in the inscribed regions, which have undergone photo induced changes, have been evaluated by using the nanoindentation technique. Results show that the hardness and elastic modulus of the photo-modified glasses are significantly lower as compared to the other locations in the waveguide, which tend to be similar to those of the unexposed areas. The observed mechanical effects are found to correlate well with the optical properties of the waveguides. Further, based on the results, the minimum threshold values of hardness and elastic modulus for the particular propagation mode of the waveguide (single or multi), has been established

Structure, Optical And Electrical Characterization Of Tin Selenide Thin Films Deposited At Room Temperature Using Thermal Evaporation Method

Tin Selenide (SnSe) is an important IV-VI compound semiconducting material used for various devices like memory switching, an efficient solar cell and holographic recording systems. SnSe thin films of the thickness of 100 nm were deposited by thermal evaporation method on a Glass substrate at room temperature. The prepared samples were investigated for structural, compositional, morphological and optical characte-rization respectively by using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission measurements. Thus deposited films showed a good polycrystalline quality having preferred (111) orientation with uniformly distributed spherical grains having size 16nm.The grown film identified as P- types by hot probe method. The films were found to have direct band transition having an optical bandgap (Eg) of 1.92 eV at room temperature. The temperature depended electrical resistivity (ρ) determined by using the two probe method, found to be 390 Ω·m at room temperature. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/952

Impact of annealing on CuInSe2 thin films and its Schottky interface

The room temperature current–voltage (I-V) characteristics of the Al/p-CuInSe2 Schottky Diodes fabricated on thermally evaporated CIS thin films, before and after annealing, were studied. Prior to their diode formation, the undertaken CIS thin films were compared on the basis of structural, morphological and electrical investigations. Wherein, annealed films showed an increase in the grain size and carrier concentration values while decrease in resistivity. I-V analysis of the Schottky diodes depicted decrease in the barrier heights and increase in ideality factors of those formed on annealed films. The diodes, thus, indicated the existence of barrier inhomogenity at the M-S interface. The annealed Schottky diodes also demonstrated better ideality factor values with increased thickness of CIS layer. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2792

Pattern of panic-buying and its psychosocial correlates among Pakistani adults during COVID-19 pandemic

Background: As the COVID-19 pandemic rages on, one bizarre yet ubiquitous human behavior has resurfaced. Globally, people have engaged in panic buying and hoarding (PBH). This irrational practice of panic buying is driven by deficient, manipulated news amid COVID-19 crisis.Methods: A cross-sectional study was conducted with Pakistani adults (≤18 years). Data was collected through an anonymous self-reported online survey from 17th April 2020 (0800 hours) through 20th April 2020 (2200 hours) via social media platforms. The survey consisted of sociodemographic characteristics, questions regarding food/essential supplies PBH and its psychosocial correlates- attitudes about COVID-19 severity (CA), values related to social responsibility (SR), social trust (ST), and self-interest (SI). Data was entered and analyzed using IBM Statistical package for social sciences (SPSS) version 20.Results: There were 786 participants in the survey; 59% were females. Mean age was 26.6±7.6 years. Mean PBH score was 2.31±0.85 (range: 1-5). Overall, 28.4% hoarded supplies a few times or more and 47% agreed to have bought more food/essential supplies due to COVID-19. Correlation analysis showed a 12.3% positive correlation of PBH with ST and 8.5% positive correlation with SI (p<0.05). In the multivariate regression model, PBH showed a statistically significant (p<0.05) positive impact on ST and SI.Conclusions: More than one-fourth of the individuals indulged in panic buying and hoarding during the COVID-19 in Pakistan. Fear of contracting the virus and uncertainty about the duration of lockdown was the common reasons behind PBH. Social trust and self-interest were significant psychosocial contributors to hoarding behavior.