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根据12条地波路径实测得到的地波二次相位因子和基准场强的数据,探讨了在处理地波传播问题时等效地球半径系数α的取值问题。分析表明：在我国内陆,α选用4/3较宜。 相似文献
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本文对蒲城至东风、昆明、上海三条传播路径BPL地波场强监测数据进行了统计分析。给出了我国西北、东南、西南等效地面电导率σ在暖季与冬季的区别,以及由σ变化引起的低频地波二次相位因子变化的程度。 相似文献
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罗兰导航系统(Long range navigation)是全球卫星导航系统的有效备份和补充.罗兰信号以地波形式沿地球表面传播,随着传播距离的增加,地波信号受到地面电参数的影响会出现一定程度的传播延时,信号的场强也会逐渐减弱.为分析我国西部罗兰台站的定位性能,从理论角度分析了不同介质类型中二次时延随距离的变化关系,并结合电磁波传播规律计算了场强随距离的变化.根据罗兰接收机最低性能标准,分析了西部台站的覆盖区域以及定位范围,计算了定位区域内的几何精度因子,结果显示定位范围内大部分区域的几何精度因子小于6.在计算区域内仿真西部台站定位误差,分析结果表明:就定位而言,西部台站几何布局较为合理,但是由于二次时延的影响,纬度和经度方向定位误差较大,必须采用差分等抑制观测误差的方法提高定位精度.为扩大西部罗兰台站的定位覆盖区域,接收机的接收能力有待提升. 相似文献
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1978年初至1981年初,我们用陕台光电等高仪(Ⅰ型)进行了专门的星表观测。获得的星表包括777颗两次过等高圈的恒星的赤径改正△α和赤纬改正△δ。其中有FK4星357颗,FK4supp星189颗,GC星231颗。对于|cosq|≤0.3的星没有计算△δ。所有FK4星△α、△δ的平均精度分别为±0.0036和±0″.063。另外,还给出了43颗一次过等高圈的恒星的赤经改正△α和2颗星的赤纬改正△δ。为有效地扩充待测星数,除在时间、纬度观测纲要即基本组(2小时一组)内插入适当数目的待测星外,我们增加了星表组(1小时一组)。观测方案是:星表组——基本组——星表组——星表组——基本组——星表组或者星表组——基本组——基本组——星表组。星表的系统完全由基本组的FK4星决定。将各基本组化到平均系统以后,所有的星表组及基本组内的插入星直接相对于这个平均系统求其残差平均值。 相似文献
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《时间频率公报》2001,(6)
2(X)1年 6月 日开始结束级别ENDI倒[P驴A1‘FSPA班认VLFI‘F(甘r)(UT)仰(脾)△和(脚)△和(脾)从(dB) 一0 .9 一1 .2一4 .3, 4.7一8 .5, 11.3 一6,8只U7月J月峥40. 0. 8. 6.2.一一一一一87护02,i ;…n︸0咤曰护02一一一一一一一十一十,几弓且q口内J,l0456051108盯0444060505020515081904570615051005220910D0550D断22nn甘2 seUO久甘︵U ..…护O︵吕2月峙乙. 72飞曰月,2 ..…n︸,几1二2七」一一一一一子O︷U 2 20 ,.…n︸,几1几1二,︸一一一一一4 70了0矛O ..…久曰1人2 132一一一一一月峙,五心J成、J‘U :,:傀︼,二月工月… 相似文献
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《时间频率公报》2001,(9)
2(X)1年 9月 日开始结束级别ENDI洲[PSPA1.卫SPA班认VLFI万(UT)(UT)仰(娜)△和(娜)△和(牌)△A(dB)3 OJ QOO才R︸,几,工,二,几心」一 一八JO才4C甘240愧甘2傀曰一一一一一‘U OJC︸矛O‘J傀甘0飞︸,几2一一一一一一一1.7一一2.0, 2.2一一2.7一一0.7一一3.4飞口,JO矛O矛内」2心J嘴l月峥2一一一一一,几O八︸7内J尹O2内J弓1 42一一一一一0解00655呢刀050701160350071502350514似01沙拼008400310063303500 7 7 4 ro21人2久曰2 一一十一一月JC甘内吕,工O子,臼门‘弓太,几,工一一一一一0月,70护b2,11占1几月几一一一一一O5(… 相似文献
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张子进 《中国天文和天体物理学报》1983,(2)
本文提供一种新方法、以求某天体的引力红移、速度红移和质量,只要事先知道它的红移观测值和偏转角观测值(指的是它的发射线掠过折射天体如太阳所弯曲的角度或者引力透镜中的有关数据)。 所要用的基本公式如下:(一)光线弯曲与光谱频移关系式式中φ为偏转角,GM/c~2R为折射天体无量纲表面引力势,z_(v1)和z_(v2)分别为射线掠过折射天体之前和之后的引力红移。(二)引力红移相加法则 z_v=z_(v1) z_(v2) z_(v1)·z_(v2)。式中Z_r为总的引力红移。(三)引力红移变换式△c/c=z_λ z_v z_λ·z_v。式中△c/c为光速变化率,只要它为已知,则引力红移的两种表示式z_λ和z_v可以相互交换得到。通过这种变换,式(二)可以变成z_λ=z_(λ1) z_(λ2) z_(λ1)·z_(λ2),而形式完全相同.我们叫它为引力红移相加法则是变换不变的。(四)光速变化率。它是根据广义相对论的公式c=c_0(1-2U)(1 2U)~(-1)推得的。式中c_0为真空中光速,c_A、c_C和U_A、U_C分别为场中A、C两点的光速和无量纲引力势。(五)引力红移和速度红移相加法则。Z_λ=z_(λ0) z_λ z_(λ0)·z_λ 式中z_(λ0)为速度红移,Z_λ为红移观测值。我认为波λ和频率v在描述自然规律方面应有同等作用,即通过类似的红移变换,此红移相加法则的形式仍然不变。 相似文献
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We have made an analysis of the observed equivalent widths of the lines of Lyman and Werner bands by Smith. The H2 column densities of 3×1019 to 1020 and the excitation temperature of 80 to 150 K satisfy the observations. This temperature refers to the kinetic temperature. We have also discussed the importance of getting the excitation temperature from lines of H2 and other heteronuclear diatomic molecules for the same star and from different regions of space. 相似文献
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K. S. Krishna Swamy 《Astrophysics and Space Science》1977,49(2):389-398
We have calculated the expected equivalent widths of the individual rotational lines of the Lyman band of H2 and (A-X) band of CO and SiO for Main Sequence stars. The results indicate that the lines of H2 should be observable in absorption up toT
e9000 K. The lines of CO are found to be much weaker than those of H2 lines. A discussion of these results is presented. 相似文献
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K. S. Krishna Swamy 《Solar physics》1975,41(2):301-312
The expected equivalent widths of the individual rotational lines of the Lyman and Werner bands of the hydrogen molecule from the solar atmosphere have been calculated. These results are used to predict what one expects to observe with a specified wavelength bandpass. These are compared with the observation of Dupree and Reeves. 相似文献
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Gang Zhao Yu-Qin Chen Hong-Mei QiuNational Astronomical Observatories Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2002,2(4)
We present the equivalent widths of 15 extrasolar-planet host stars. These data were based on the high-resolution, high signal-to-noise ratio spectra obtained with the 2.16m telescope at Xinglong station. The error in the Xinglong equivalent width is estimated by a comparison of these data with those given in previous studies of common stars. 相似文献
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K. S. Krishna Swamy 《Solar physics》1976,47(2):469-474
The expected equivalent widths of the individual rotational lines of (A - X) band of CO and SiO has been calculated for the solar atmosphere. Some of these results are discussed. 相似文献
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H. M. Yehia 《Celestial Mechanics and Dynamical Astronomy》1987,41(1-4):275-288
The general problem of motion of a rigid body about a fixed point under the action of stationary non-symmetric potential and gyroscopic forces is considered. The equations of motion in the Euler-Poisson form are derived. An interpretation is given in terms of charged, magnetized gyrostat moving in a superposition of three classical fields. As an example, the problem of motion of a satellite — gyrostat on a circular orbit with respect to its orbital system is reduced to that of its motion in an inertial system under additional magnetic and Lorentz forces.When the body is completely symmetric about one of its axes passing through the fixed point, the above problem is found to be equivalent to another one, in which the body has three equal moments of inertia and the forces are symmetric around a space axis. The last problem is well-studied and the given analogy reveals a number of integrable cases of the original problem. A transformation is found, which gives from each of these cases a class of integrable cases depending on an arbitrary function. The equations of motion are also reduced to a single equation of the second order. 相似文献
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The local face-on disk galaxies are selected as galaxy sample from the main galaxy sample of the Seventh Data Release of Sloan Digital Sky Survey (SDSS DR7). The correlations between the colors and sizes of disk galaxies with equivalent total stellar masses are statistically investigated and their realities are tested. It is found that for the disk galaxies with equivalent masses, the correlation between u-r color and size is very weak. However, there are anticorrelations between g-r, r-i, r-z colors and sizes, i.e., the larger are the sizes of galaxies, the bluer are their colors. This result means that the mass distribution of disk galaxies has a significant influence on their star formation history. The galaxies with more extended mass distributions evolve more slowly. 相似文献
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H. M. Yehia 《Celestial Mechanics and Dynamical Astronomy》1987,41(1-4):289-295
The problem of motion of a dynamically symmetric gyrostat acted upon by non-symmetric potential forces admitting a cyclic integral is considered. This problem is brought into equivalence with another one concerning the motion of a similar gyrostat under the action of axisymmetric potential forces. Using this analogy, new integrable cases of each of the two problems are obtained from the known cases of the other. The equations of motion are reduced to a single equation of the second order. 相似文献
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为准确预报地波传播时延,用电波传播法对关中平原的大地等效电导率进行了间接测量。阐述了电波传播法的测量原理和方法,第一次给出关中平原大地等效电导率的间接测量结果,同时,给出了中国科学院国家授时中心临潼科研楼参考点的BPL信号传播时延测量结果,并对这些测量结果进行了精度分析。 相似文献