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71.
Rabindra N. Mohapatra Goran Senjanović 《Zeitschrift fur Physik C Particles and Fields》1983,20(4):365-367
We suggest soft breaking of Peccei-Quinn symmetry as a simple solution to the strongCP problem without the presence of the axion. In the context of theSU(2) L ×U(1) model, it is shown how settingθ tree=0 keeps θ calculable and, furthermore, extremely small: θ?10?16. Unlike in the case of the axion the model is free from the cosmological domain wall problem. Possible extension of this idea to grand unification is discussed. 相似文献
72.
In unified gauge theories with massive “color” gluons, the physical requirement of maintaining “color” SU(3) as a global classification symmetry is shown to lead to the following restrictions: (i) the local unifying symmetry group must be of the form Gflavor?Gcolor; (ii) quarks are to be integer charged; (iii) the number of flavors is an integral multiple of the number of “colors”. 相似文献
73.
In the present communication, we report a model Hamiltonian to study the interplay between the two long range orders of anti-ferromagnetism
(AFM) and superconductivity (SC) in cuprate superconductors in presence of the intersite pairing effect. The BCS type but
non-phonon pairing mechanism is considered among the electrons of two equivalent ‘Cu’ sites. The pairing among the electrons of two nearest neighbour non-equivalent ‘Cu’ sites is included in the Hamiltonian and its effect on the interplay of SC and AFM is investigated. The Hamiltonian is solved
by the Green’s function method and the corresponding gap equations are calculated and solved selfconsistently. The influence
of model parameters like AFM coupling (λ), SC couling (λ
1) and the coupling (λ
2) for intersite superconducting interactions on the gaps (SC and AFM) are studied numerically and the results are reported. 相似文献
74.
<正>Adaptive grid methods are established as valuable computational technique in approximating effectively the solutions of problems with boundary or interior layers. In this paper,we present the analysis of an upwind scheme for singularly perturbed differential-difference equation on a grid which is formed by equidistributing arc-length monitor function.It is shown that the discrete solution obtained converges uniformly with respect to the perturbation parameter.Numerical experiments illustrate in practice the result of convergence proved theoretically. 相似文献
75.
The objective of the current research deals with the experimental study of an air-atomized spray with surfactant-added water, cooling a 12-mm-thick AISI-1020 stationary steel plate at three different initial surface temperatures (400°C, 600°C, and 900°C). Furthermore, the effects of surfactant concentration and airflow rate on the cooling rate have been investigated. The surface heat flux and surface temperature show a significant improvement in cooling for all three cases of initial surface temperatures when the air-atomized spray was used with surfactant-added water. 相似文献
76.
This article focuses on the phase transformation of zirconia (ZrO2) nanoparticles produced from zircon using a bottom-up approach. The influence of mechanical milling and thermal annealing on crystalline phase transformation of ZrO2 nanoparticles was explored. It was found that the iron oxide, as an inherent impurity present in ZrO2 nanoparticles, produced from zircon stabilises the cubic phase after calcination at 600°C. The stabilised cubic phase of ZrO2 nanoparticles was disappeared and transformed into partial tetragonal and monoclinic phases after mechanical milling. The phase transformation occurred on account of the crystal defect induced by high-energy mechanical milling. The destabilisation of cubic phase into monoclinic phase was observed after the thermal annealing of ZrO2 nanoparticles at 1000°C. The phase transitions observed are correlated to the exclusion of iron oxide from the zirconia crystal structure. 相似文献
77.
Rosner JL Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Riley D Ryd A Sadoff AJ Shi X Stroiney S Sun WM Wilksen T Athar SB Patel R Yelton J Rubin P Eisenstein BI Karliner I Mehrabyan S Lowrey N Selen M White EJ Wiss J Mitchell RE Shepherd MR Besson D Pedlar TK Cronin-Hennessy D Gao KY Hietala J Kubota Y Klein T Lang BW 《Physical review letters》2008,100(22):221801
We exploit the quantum coherence between pair-produced D0 and D[over]0 in psi(3770) decays to study charm mixing, which is characterized by the parameters x and y, and to make a first determination of the relative strong phase delta between D0-->K+pi- and D[over]0-->K+pi-. Using 281 pb(-1) of e+e- collision data collected with the CLEO-c detector at Ecm=3.77 GeV, as well as branching fraction input and time-integrated measurements of RM identical with (x2 + y2)/2 and RWS identical with Gamma(D0-->K+pi-)/Gamma(D[over]0-->K+pi-) from other experiments, we find cosdelta=1.03(-0.17)(+0.31)+/-0.06, where the uncertainties are statistical and systematic, respectively. By further including other mixing parameter measurements, we obtain an alternate measurement of cosdelta=1.10+/-0.35+/-0.07, as well as x sindelta=(4.4(-1.8)(+2.7)+/-2.9)x10(-3) and delta=(22(-12-11)(+11+9)) degrees . 相似文献
78.
79.
Mohapatra Satyabrata Manglani Nishant Krishnan Dilmel Arumugam Ilavarasu Vijayakumar Madhavan Babu Uddagiri V. 《平面色谱法杂志一现代薄层色谱法》2014,27(4):251-254
JPC – Journal of Planar Chromatography – Modern TLC - Arnebia nobilis has gained an increasing popularity for the recently recognized various pharmacological activities. The root part... 相似文献
80.