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111.
Amitava Datta 《Pramana》1993,40(6):L503-L509
It is argued with the help of an illustrative model, that the inter species hierarchy among the fermion masses and the quark
mixing angles can be accommodated naturally in the standard model with (approximate) flavor democracy provided there are three
exactly massless neutrinos and four families of sequential quark-leptons with all members of the fourth family having roughly
equal masses. The special problem of light neutrino masses (if any) and possible solutions are also discussed. 相似文献
112.
粲夸克偶素强衰变之谜 总被引:1,自引:0,他引:1
北京正负电子对撞机的最新实验研究结果在高灵敏度水平上展出了粲夸克偶素物理中的强衰变之谜,新反常衰变道的发现突破了这个谜的原有图像,对理论提出了新的挑战。 相似文献
113.
Debajyoti Choudhury Saurabh D. Rindani B. Ananthanarayan K. R. S. Balaji Debajyoti Choudhury Manuel Drees Shashikant Dugad Gautam Dutta Sukanta Dutta Naveen Gaur Ambar Ghosal Walter Grimus Ernest Ma Shubhendra Mohanty P. N. Pandita M. K. Parida Subhendu Rakshit Saurabh D. Rindani D. P. Roy Probir Roy Sarira Sahu N. N. Singh Sudhir K. Vempati Francesco Vissani 《Pramana》1998,51(1-2):305-311
This report summarises the activities of the working group on ‘Physics beyond the Standard Model’. The results of investigations
in incorporatingR-parity in grand unification, the possibility of a light charged Higgs boson in extension of MSSM and radiative generation
of neutral vector boson self-couplings within the MSSM are described. Also given is an account of activities in neutrino physics,
namely a proposal for a study of the atmospheric muon anomaly in deep underground mines, a field theoretic study of neutrino
oscillations and a mechanism to generate appropriate masses of three active plus one sterile neutrino species. 相似文献
114.
Summary In this note we describe the image acquisition system realized as a part of an experiment designed to record high-spectral-resolution
solar images in the visible part of the spectrum. The system is based on a Charge Coupled Device Thomson THX31159. The electronics
for driving the sensor and for the amplification and conditioning of the video signal has been designed and built in the laboratory,
while a VME-bus-based computer has been used for the timing of operations, for the signal A/D conversion and for image presentation
and storage.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
115.
Biswajoy Brahmachari 《Pramana》2004,62(3):631-633
We construct a model where neutrino Majorana masses are small and hierarchical but where neutrinoless double beta decay occurs
at an observable rate potentially detectable by present day experiments. 相似文献
116.
Stephen J. Sugden 《Applied Mathematical Modelling》2004,28(12):1635-1082
The view factor (angle factor) for a differential inclined plane in the case of a radiating source of radially Gaussian intensity is considered. This information is useful for modelling of solar radiation in certain applications. The view factor is expressed in terms of two integrals, one of which is obtained in closed form in terms of special functions, and the other is approximated. A compact estimate for the view factor is presented which is suitable for machine computation. While the relative error associated with the final estimate is typically less than 0.01%, and in all cases, less than 0.2%, the method is easily extended to yield even greater accuracy. 相似文献
117.
Summary Solar-wind data, as obtained in the near-Earth space, have been re-examined for the period 1964 to 1987. For each month, the
maximum and minimum hourly values of the solar-wind bulk speed together with those for the interplanetary magnetic-field intensity
have been selected. They are reported in a tabular form (available as readable ASCII text files on DOS-formatted floppy disks)
to ease off further studies in the framework of the Solar-Terrestrial System. 相似文献
118.
继承异常用来描述在并发面向对象语言中继承与并发的冲突.对继承异常做了系统的分析,给出一种新的分类.提出在一并发对象中将同步部分与顺序部分分离,生成两个对象,通过将同步代码放入一单独对象,将继承过程分为顺序部分和同步部分,这种分离大大地减少了继承异常的发生. 相似文献
119.
Dimuon events induced by charm-quark productions from neutrino deep inelastic scattering (DIS) processes have been studied in traditional DIS experiments for decades. The recent progress in neutrino telescopes makes it possible to search for such dimuon events at energies far beyond the laboratory scale. In this study, we construct a simulation framework to calculate yields and distributions of dimuon signals in an IceCube-like km3 scale neutrino telescope. Owing to the experimental limitation in the resolution of double-track lateral distance, only dimuons produced outside the detector volume are considered. Detailed information about simulation results for a 10-year exposure is presented. As an earlier paper[Physical Review D 105, 093005 (2022)] and ours report on a similar situation, we use that paper as a baseline to conduct comparisons. We then estimate the impacts of different calculation methods of muon energy losses. Finally, we study the experimental potential of dimuon searches under the hypothesis of single-muon background only. Our results based on a simplified double-track reconstruction indicate a moderate sensitivity, especially with the ORCA configuration. Further developments on both the reconstruction algorithm and possible detector designs are thus required and are under investigation. 相似文献
120.
A PEC cell with nanostructured BiVO4 photoelectrode film presents outstanding azo dye degradation and simultaneous H2 production performance. 相似文献