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排序方式: 共有509条查询结果,搜索用时 11 毫秒
1.
We study the neutrino mass hierarchy at the magnetized Iron CALorimeter (ICAL) detector at India-based Neutrino Observatory with atmospheric neutrino events generated by the Monte Carlo event generator Nuance. We judicially choose the observables so that the possible systematic uncertainties can be reduced. The resolution as a function of both energy and zenith angle simultaneously is obtained for neutrinos and anti-neutrinos separately from thousand years un-oscillated atmospheric neutrino events at ICAL to migrate number of events from neutrino energy and zenith angle bins to muon energy and zenith angle bins. The resonance ranges in terms of directly measurable quantities like muon energy and zenith angle are found using this resolution function at different input values of θ13. Then, the marginalized χ2s are studied for different input values of θ13 with its resonance ranges taking input data in muon energy and zenith angle bins. Finally, we find that the mass hierarchy can be explored up to a lower value of θ13≈5° with confidence level >95% in this set up. 相似文献
2.
The new class of higher dimensional cosmological model of the early universe filled with perfect fluid source in the framework of f(R,T) theory of gravity (Harko et al. in Phys. Rev. D 84, 024020, 2011) is considered. A cosmological model with an appropriate choice of the function f(T) has been constructed. The physical behavior of the model is studied. The well known astrophysical phenomena, namely the Hubble parameter H(z), luminosity distance (d L ) and distance modulus μ(z) with redshift are discussed. 相似文献
3.
G. C. Samanta 《International Journal of Theoretical Physics》2013,52(12):4389-4402
In this paper, author studied homogeneous and anisotropic Bianchi type-V universe filled with matter and holographic dark energy (DE) components. The exact solutions to the corresponding Einstein’s field equations are obtained for exponential and power-law volumetric expansion. The holographic dark energy (DE) EoS parameter behaves like constant, i.e. ω Λ =?1, which is mathematically equivalent to cosmological constant (Λ) for exponential expansion of the model, whereas the holographic dark energy (DE) EoS parameter behaves like quintessence for power-law expansion of the model. A correspondence between the holographic dark energy (DE) models with the quintessence dark energy (DE) is also established. Quintessence potential and dynamics of the quintessence scalar field are reconstructed, which describe accelerated expansion of the universe. The statefinder diagnostic pair {r,s} is adopted to characterize different phases of the universe. 相似文献
4.
Dhruba Gupta C Samanta R Kanungo P Basu Subinit Roy S Kailas A Chatterjee B J Roy K Mahata A Samant A Shrivastava 《Pramana》2001,57(1):209-213
Inclusive cross sections of α particles and tritons from the breakup of 42 MeV 7Li by 12C and 197Au targets are presented and analysed in the framework of the Serber model. Spectral distortions due to the targets and relevant
reaction mechanisms are discussed. 相似文献
5.
G. K. Dalapati S. Chatterjee S. K. Samanta C. K. Maiti 《Applied Surface Science》2003,210(3-4):249-254
Thin films of titanium dioxide have been deposited on strained Si0.82Ge0.18 epitaxial layers using titanium tetrakis-isopropoxide [TTIP, Ti(O-i-C3H7)4] and oxygen by microwave plasma enhanced chemical vapor deposition (PECVD). The films have been characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Dielectric constant, equivalent oxide thickness (EOT), interface state density (Dit), fixed oxide charge density (Qf/q) and flat-band voltage (VFB) of as-deposited films were found to be 13.2, 40.6 Å, 6×1011 eV−1 cm−2, 3.1×1011 cm−2 and −1.4 V, respectively. The capacitance–voltage (C–V), current–voltage (I–V) characteristics and charge trapping behavior of the films under constant current stressing exhibit an excellent interface quality and high dielectric reliability making the films suitable for microelectronic applications. 相似文献
6.
M.H. Majles Ara SR. Hosseini M.H. Rezvani M. Abolhassani 《Journal of Physics and Chemistry of Solids》2011,72(11):1367-1372
In this paper, the parametric scattering of a single extraordinary polarized beam of laser in BaTiO3 photorefractive crystal has been investigated experimentally and theoretically. The resulting pattern consists of beam fanning, isotropic ring, and anisotropic one. Among all parts of scattering pattern, isotropic ring has not been studied as much as beam fanning and anisotropic ring, and there still are some differences in reports about it. Therefore, the study has mainly focused on this part. In this experimental configuration, isotropic ring is just visible in positive angles although the other parts of parametric scattering pattern can be visible from behind and in front of the crystal. In addition to steady state pattern in forward and backward directions, its transient behavior with the rotation of crystal has been studied. The results of experiments have been analyzed carefully, and their theoretical explanations have been presented based on the standard theory of parametric scattering in photorefractive crystals. It has been shown that this configuration corresponds to the so called parametric B-process scattering. 相似文献
7.
Stable, high-power, second-harmonic-generation (SHG) of a compact CW Ytterbium (Yb) fiber laser at 1064 nm into the green
and its use as a pump source for CW singly-resonant optical parametric oscillator (SRO) is demonstrated. Using a simple single-pass
SHG configuration in MgO:sPPLT, as much as 9.6 W of single-frequency green radiation at 532 nm is generated from 30 W of fundamental
power at a conversion efficiency of 32.7% in a Gaussian spatial profile with a beam quality factor of M
2 < 1.3. Thermal effects have been investigated at different fundamental power levels and various thermal management schemes
are employed to maximize the second-harmonic power. The green source is successfully deployed to pump a CW SRO tunable over
855–1408 nm, generating up to 2.1 W of idler at 1168 nm. The peak-to-peak idler power stability is better than 10.7% over
40 min, with beam quality factor M
2 < 1.26 for the idler and M
2 < 1.52 for the signal. 相似文献
8.
We have studied CPT violation in neutrino oscillation considering three flavor framework with matter effect. We have constructed a new way to find the oscillation probability incorporating CPT violating terms without any approximation. Then CPT violation with atmospheric neutrinos for a magnetized iron calorimeter detector considering the muons (directly measurable with high resolution) of the charge current events has been studied for zero and nonzero θ13 values. It is found that a potential bound of δb32?6×10−24 GeV at 99% CL can be obtained with 1 Mton.year exposure of this detector; and unlike neutrino beam experiments, there is no possibility to generate ‘fake’ CPT violation due to matter effect with atmospheric neutrinos. The advantages of atmospheric neutrinos to discriminate CPT violation from CP violation and nonstandard interactions are also discussed. 相似文献
9.
Optics has already been proved as a successful candidate for conducting parallel logic, arithmetic and algebraic operations. Several all-optical data processors were proposed since last few decades. To implement these systems, different data encoding decoding techniques such as polarization encoding, tristate, quartenary state, multivalued state, symbolic substitution technique etc. have already been proposed. All these are done to use optics in a suitable platform. We propose here a new concept of encoding data by adopting frequencies variation technique for conducting a inversion operation successfully. 相似文献
10.
A simple electrochemical process has been implemented to fabricated fractal structured leaf-like metallic zinc. The fabricated material was structurally characterized using X-ray diffraction that reveals the hexagonal unit cell structure. Also the growth of the structure is anisotropic. Field emission scanning electron microscopic images revealed clearly the leaf-like morphology of the fabricated material is fern like and ∼500 μm in length, ∼50-60 μm wide and the platelets thickness is ∼5 μm. The growth of this structure is diffusion controlled and locally accomplished with the oriented attachment. Raman shift measurement revealed the existence of surface optical phonon modes which is very significant for surface defects. 相似文献