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101.
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We report a novel mounting of the reference cavity used for stabilization of the clock laser in an optical frequency standard. The cavity axis is oriented horizontally and the cavity is supported in its horizontal symmetry plane on four support points. The positions of the points were optimized by finite-element analysis. A sensitivity to accelerations of 1.5 kHz/(m/s2) in the vertical and 14 kHz/(m/s2) in the horizontal direction was measured, which is a reduction in the vertical sensitivity by two orders of magnitude compared to the usual support from below. PACS 42.60.Da; 46.70.Lk; 42.62.Fi 相似文献
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F. Vogt Ch. Grain T. Nazarova U. Sterr F. Riehle Ch. Lisdat E. Tiemann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(1):73-79
Photoassociation spectroscopy was used to determine the s-wave scattering length of 40Ca atoms in their electronic ground state. Vibrational levels were observed in an extended range of up to 182 GHz below the
dissociation limit 4s2
1S0–4s4p 1P1. Thus, the frequency interval was nearly tripled, in which photoassociation was observed compared to previous measurements.
The spectra were analyzed by means of quantum mechanical simulations. With the new data it was possible to resolve the discrepancy
concerning the ground state scattering length presented in earlier publications [Phys. Rev. A 67, 043408 (2003); Eur. Phys. J. D 26, 155 (2003)]. An improved dipole-dipole coupling constant C3
Σ = 0.52306(20) ×103 cm-1 nm3 is obtained. 相似文献
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WANG Yue BI Xiao-Jun CUI Shu-Wang DING Lin-Kai DAN Zeng-Luo-Bu DING Xiao-Hong FAN Chao FENG Cun-Feng FENG Zhao-Yang FENG Zhen-Yong GAO Xiao-Yu GENG Qing-Xi GUO Hong-Wei HE Hui-Hai HE Mao HU Hai-Bing HU Hong-Bo HUANG Qing JIA Huan-Yu LA Ba-Ci-Ren LE Gui-Ming LI Ai-Feng LI Jin-Yu LOU Yu-Qing LU Hong LU Sui-Ling MENG Xian-Ru MU Jun REN Jing-Ru TAN You-Heng WANG Bo WANG Hui WANG Yong-Gang WU Han-Rong XUE Liang YANG Xian-Chu YE Zong-Hai YU Guang-Ce YUAN Ai-Fang ZHANG Hui-Min ZHANG Ji-Long ZHANG Nai-Jian ZHANG Xue-Yao ZHANG Yong ZHANG Yi ZHA Xi-Sang-Zhu ZHOU Xun-Xiu YUAN Qiang 《中国物理C(英文版)》2008,32(11)
Using the data taken from Tibet Ⅱ High Density (HD) Array (1997 February--1999 September) and Tibet-Ⅲ array (1999 November--2005 November), our previous northern sky survey for TeV γ-ray point sources has now been updated by a factor of 2.8 improved statistics. From 0.0° to 60.0° in declination (Dec) range, no new TeV γ-ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV T-ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits. 相似文献
108.
109.
V. F. Kucherov B. G. Kovalev I. I. Nazarova L. A. Yanovskaya 《Russian Chemical Bulletin》1960,9(8):1405-1407
Summary The reaction of carbethoxymethylenetriphenylphosphorane with various aldehydes is a general method of synthesizing esters of ,-unsaturated and polyenoic acids. 相似文献
110.