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A. D. Panov J. H. Adams Jr. H. S. Ahn G. L. Bashindzhagyan J. W. Watts J. P. Wefel J. Wu T. G. Guzik V. I. Zatsepin J. Isbert K. C. Kim M. Christl E. N. Kouznetsov M. I. Panasyuk E. B. Postnikov E. S. Seo N. V. Sokolskaya J. Chang 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(3):319-322
A strong anomaly in form of a wide peak in the energy range 300–800 GeV was discovered in the first measurements of the electron spectrum in the energy range from 20 GeV to 3 TeV by the balloon-borne experiment ATIC [1]. The experimental data processing and analysis of the electron spectrum with different criteria for selection of electrons completely independent of the results reported in [1] is employed in the present paper. New independent analysis generally confirms the results of [1] but shows that the spectrum in the region of the anomaly is represented by a number of narrow peaks. Measured spectrum is compared to the spectrum of [1] and to the spectrum of the Fermi/LAT experiment. 相似文献
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Carbon-13 shieldings and one-bond 13C? H coupling constants of bicyclo[2.1.1]hexane, bicyclo[2.1.1]hex-2-ene, tricyclo[3.1.1.02,4]heptane and benzvalene are presented and compared to the data of related compounds. If a bicyclo[3.1.0]hexane system is part of a rigid skeleton, the cyclopropane ring exerts specific γ substituent effects of two kinds. In the case of the bicyclohexane boat form an upfield shift of the C-3 signal is observed and in the case of the chair form a downfield shift of 15–20 ppm. Compared to the corresponding cyclopentanes the double bond in strained cyclopentenes causes downfield shifts of the C-4 absorption. This effect increases with increasing strain, reaching a 45.9 ppm maximum in benzvalene. Hence it is the only known bicyclo[1.1.0]butane having a reversed order of carbon shieldings. The downfield shifts are explained by means of simple orbital interaction schemes. 相似文献