布莱恩(J.B.Bryan)建议的应用一例

阿贝(Abbe)原则是进行长度测量的指导性原则。它指出:若要得到正确的测量结果,必须将仪器的读教刻度尺放在被测尺寸线的延长线上.根据此原则,制造了阿贝比长仪,进行绝对测量.一般测长仪器的测量值,可用下式表示式中S为刻度尺到被测物的垂直距离,,△θ为量爪的角位移.如图1所示,可见误差由S和△θ这两个因素引出.阿贝原则恰能使S=0. 由于阿贝原则难于应用于一般测量仪器,故布莱恩建议修改阿贝原则:位移测量系统工作点的路程应和被测位移作用点的路程位于一条直线上;或者必须使传送位移的导轨没有角运动,或者必须用实际角运动的数据计算偏移…     

Annual Cumulative Contents of Volume B11.Chinese Journal of Lasers(2002)

·ＬＡＳＥＲＤＥＶＩＣＥＳ·ＥｘｐｅｒｉｍｅｎｔａｌＳｔｕｄｙｏｎＡｃｔｉｖｅ ｐａｓｓｉｖｅＭｏｄｅ ｌｏｃｋｉｎｇＵｓｉｎｇＣｒ4 + ∶ＹＡＧａｓＳａｔｕｒａｂｌｅＡｂｓｏｒｂｅｒ1 61 1ＡＭｉｃｒｏｃｈｉｐＴｕｎａｂｌｅＢｌｕｅＬａｓｅｒＳｏｕｒｃｅＢａｓｅｄＵｐｏｎＣｒ∶ＬｉＳＡＦｉｎＣｏｎｔａｃｔｗｉｔｈＫＮＣｒｙｓｔａｌ1 61 5ＨｉｇｈＰｏｗｅｒ 940ｎｍＡｌ ｆｒｅｅＡｃｔｉｖｅＲｅｇｉｏｎＬａｓｅｒＤｉｏｄｅｓａｎｄＢａｒｓｗｉｔｈａＢｒｏａｄＷａｖｅｇｕｉｄｅ1 61 91 .3 2 μｍＮｄ3+ ∶Ｙ…     

向心力实验器(B型)

为了满足从八四年秋开始使用的高中物理乙种本《验证向心力公式》学生实验的需要,我们了设计专供这一实验使用的向心力实验器(B型)。兹将该仪器的结构、原理和实验方法等介绍如下,供参考. 一、仪器结构向心力实验器(B型)的结构,如图1所示。它由     

First observation of the decays B(0) → D(+)K(-)π(+)π(-) and B(-) → D(0)K(-)π(+)π(-)

First observations of the Cabibbo-suppressed decays B(0) → D(+)K(-)π(+)π(-) and B(-) → D(0)K(-)π(+)π(-) are reported using 35 pb(-1) of data collected with the LHCb detector. Their branching fractions are measured with respect to the corresponding Cabibbo-favored decays, from which we obtain B(B(0) → D(+)K(-)π(+)π(-))/B(B(0) → D(+)π(-)π(+)π(-))=(5.9±1.1±0.5)×10(-2) and B(B(-) → D(0)K(-)π(+)π(-))/B(B(-) → D(0)π(-)π(+)π(-))=(9.4±1.3±0.9)×10(-2), where the uncertainties are statistical and systematic, respectively. The B(-) → D(0)K(-)π(+)π(-) decay is particularly interesting, as it can be used in a similar way to B(-) → D(0)K(-) to measure the Cabibbo-Kobayashi-Maskawa phase γ.     

不等质量(1/2—■/2)或(1/2-1/2)电磁束缚系统的近似B.S.波函数

本文求解了不等质量(1/2—■/2)电磁束缚系统的Bethe-Salpeter方程。给出了这类系统的近似B. S. 波函数,利用复合粒子量子场论的微扰展开,在精确到O(α)的量级下,计算了■的衰变率和分支比,结果是■(1/秒)■类似地,还讨论了■过程.     

B. 变像管诊断技术

本文评述了变像管诊断技术的国内外最新发展,详细地分析介绍了本届会议上出现的几种新管型,并涉及到某些应用。     

Comment on “Relativistic atomic data for W XLVII” by S. Aggarwal et al. [Chin. Phys. B 24(2015)053201]

Recently, S. Aggarwal et al. [Chin. Phys. B 24(2015) 053201] reported energy levels, radiative rates, and lifetimes for the lowest 148 levels belonging to the 3s23 p, 3s3p2, 3s23 d, 3s3p3 d, 3p3, 3p23 d, 3s3d2, 3p3d2, and 3d3 configurations of Al-like tungsten. While their calculated energies for the levels and the radiative rates for transitions are correct, the reported results for lifetimes are completely wrong. According to our calculations, errors in their reported lifetimes are up to 14 orders of magnitude for over 90% of the levels. Here we report the correct lifetimes and explain the reasons for discrepancies.