University of Rajasthan

About: University of Rajasthan is a education organization based out in Jaipur, India. It is known for research contribution in the topics: Chemical shift & Derivative (chemistry). The organization has 15058 authors who have published 15733 publications receiving 117400 citations. The organization is also known as: Rajasthan University.

One-, two-, and three-particle distributions from 158A GeV/c central Pb+Pb collisions

Abstract: Several hadronic observables have been studied in central 158A GeV Pb+Pb collisions using data measured by the WA98 experiment at CERN: single pi(-) and K- production, as well as two- and three-pion interferometry The Wiedemann-Heinz hydrodynamical model has been fitted to the pion spectrum, giving an estimate of the temperature and transverse flow velocity Bose-Einstein correlations between two identified pi(-) have been analyzed as a function of k(T), using two different parametrizations The results indicate that the source does not have a strictly boost invariant expansion or spend time in a long-lived intermediate phase A comparison between data and a hydrodynamical based simulation shows very good agreement for the radii parameters as a function of k(T) The pion phase-space density at freeze-out has been measured, and agrees well with the Tomasik-Heinz model A large pion chemical potential close to the condensation limit of m(pi) seems to be excluded The three-pion Bose-Einstein interferometry shows a substantial contribution of the genuine three-pion correlation, but not quite as large as expected for a fully chaotic and symmetric source

A study of reaction rates of (n, f ) , (n,\( \gamma\)) and (n, 2n) reactions in natU and 232Th by the neutron fluence produced in the graphite set-up (GAMMA-3) irradiated by 2.33 GeV deuteron beam

Abstract: Spallation neutrons produced in the collision of a 2.33GeV deuteron beam with a large lead target are moderated by a thick graphite block surrounding the target and used to activate the radioactive samples of natU and Th put at three different positions, identified as holes “a”, “b” and “c” in the graphite block. Rates of the (n, f), (n, $ \gamma$ and (n, 2n) reactions in the two samples are determined using the gamma spectrometry. The ratios of the experimental reaction rates, R (n, 2n)/R (n, f), for 232Th and natU are estimated in order to understand the role of the (n, x n) kind of reactions in Accelerator-Driven Sub-critical Systems. For the Th-sample, the ratio is ∼ 54 (10)% in the case of hole “a” and ∼ 95 (57)% in the case of hole “b” compared to 1.73(20)% for hole “a” and 0.710(9)% for hole “b” in the case of the natU sample. Also the ratio of fission rates in uranium to thorium, natU (n, f)/ 232Th (n, f), is ∼ 11.2 (17) in the case of hole “a” and 26.8(85) in hole “b”. Similarly, the ratio 238U (n, 2n)/ 232Th (n, 2n) is 0.36(4) for hole “a” and 0.20(10) for hole “b” showing that 232Th is more prone to the (n, x n) reaction than 238U . All the experimental reaction rates are compared with the simulated ones by generating neutron fluxes at the three holes from MCNPX 2.6c and making use of the LA150 library of cross-sections. The experimental and calculated reaction rates of all the three reactions are in reasonably good agreement. The transmutation power, P norm as well as P norm/P beam of the set-up is estimated using the reaction rates of the (n, $ \gamma$ and (n, 2n) reactions for both the samples in the three holes and compared with some of the results of the “Energy plus Transmutation” set-up and TARC experiment.

Bianchi type I inflationary universe in general relativity

Abstract: In this paper, we have investigated Bianchi type I inflationary universe in the presence of massless scalar field with a flat potential. To get an inflationary solution, we have considered a flat region in which potential V is constant. The inflationary scenario of the model is discussed in detail.

Photon emission from reverse-biased silicon P- N junctions

Abstract: An analytical theory has been developed for the light emission of a reverse-biased silicon p-n junction. Based on the theory of ionization and indirect recombination of electrons and holes under high-field conditions, the relative intensity of emitted light has been derived. It is observed that the normalized results of intensity are in good agreement with the experimental results for an electron ionization length l ioe = 60 A , and a hole ionization length l ioh = 70 A . Thus it confirms the validity of this theoretical model for light emission in a reverse-biased silicon p-n junction.

Design of Square Patch Antenna with a Notch on FR4 Substrate

Abstract: The simulation and experimental results of square patch antennas having a notch and designed on FR4 substrate are reported in this paper. The notch angle is varied and different radiation properties of antennas are tested. It is found that on reducing the notch angle thetas from 180deg to 164deg, the patch resonates at a single frequency. However on reducing notch angle further, the patch starts resonating at two different frequencies. The f2/f1 ratio almost linearly increases on decreasing the notch angle. The 10dB impedance bandwidth (VSWR 2:1) of antenna increases up to notch angle 151deg but thereafter that antenna behaves simply as a dual frequency antenna with narrow bandwidth at each resonance frequency.