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141.
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143.
Yu.N. Gnedin G.V. Khozov V.M. Larionov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Observations of the X-ray binaries 4U 0115+634 and A 0535+262 performed in 1981 – 1982 revealed significant IR variabilities of these sources. 4U 0115+634 was observed twice, in the state close to X-ray activity, and in the state of low activity, thus changing from K = 7m.75 to K > 9m. A 0535+262 shows the temporal variations ranged from tens minutes to some days. The regular variations of IR brightness are suspected with teh period close to 104 s that corresponds to the period of axial rotation of neutron star in A 0535+262. The results obtained present arguments in favour of hypothesis that IR radiation is generated near the accreting neutron star and is possibly of maser nature. 相似文献
144.
红外气体分析中环境影响的补偿方法研究 总被引:6,自引:0,他引:6
环境温度、总压影响是红外气体分析中难以有效解决的主要问题之一,本文以二氧化碳气体为测量对象,采用实验手段,单片机和数据自理技术建立了环境温度、总压对红上气体分析影响的补偿数学模型和求解方法,并进行了实验验证,研究的内容为红外气体分析中影响影响的外补偿开始辟了一条新的途径,具有广阔的应用前景。 相似文献
145.
146.
Brunella Nisini Anlaug Amanda Kaas Ewine F. Van Dishoeck Derek Ward-Thompson 《Space Science Reviews》2005,119(1-4):159-179
We summarize the observations of the Infrared Space Observatory (ISO) concerning the earliest stages of the stellar formation.
The observations of samples of sources in different evolutionary stages are reviewed, addressing in particular how the physical
and chemical properties of the protostellar environments change from the pre-stellar cores to the protostars at the end of
their accretion phase. In addition, the mid-IR surveys in nearby star-forming regions are discussed, showing their implications
for the understanding of the stellar initial mass function.
Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries:
France, Germany, The Netherlands, and the United Kingdom), and with the participation of ISAS and NASA. 相似文献
147.
Jun Chen Shoujing Yin Rulin Xiao Qianxiang Xu Changsong Lin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The objectives of this study are to validate the applicability of a shortwave infrared atmospheric correction model (SWIR-based model) in deriving remote sensing reflectance in turbid Case II waters, and to improve that model using a proposed green-shortwave infrared model (GSWIR-based model). In a GSWIR-based model, the aerosol type is determined by a SWIR-based model and the reflectance due to aerosol scattering is calculated using spectral slope technology. In this study, field measurements collected from three independent cruises from two different Case II waters were used to compare models. The results indicate that both SWIR- and GSWIR-based models can be used to derive the remote sensing reflectance at visible wavelengths in turbid Case II waters, but GSWIR-based models are superior to SWIR-based models. Using the GSWIR-based model decreases uncertainty in remote sensing reflectance retrievals in turbid Case II waters by 2.6–12.1%. In addition, GSWIR-based model’s sensitivity to user-supplied parameters was determined using the numerical method, which indicated that the GSWIR-based model is more sensitive to the uncertainty of spectral slope technology than to that of aerosol type retrieval methodology. Due to much lower noise tolerance of GSWIR-based model in the blue and near-infrared regions, the GSWIR-based model performs poorly in determining remote sensing reflectance at these wavelengths, which is consistent with the GSWIR-based model’s accuracy evaluation results. 相似文献
148.
唐尧 《空间控制技术与应用》2012,38(3):27-32
本文考察了摆动式红外地球敏感器测量的工作原理,在介绍敏感器两种数学模型—圆盘模型和三维模型的基础上,增加卫星轨道高度参数为变量,讨论了在不同轨道高度下,敏感器数学模型的变化.利用小角度条件下的一阶近似处理,对敏感器模型所关心的弦宽与姿态角转换关系给出了解答.通过进行带有高度参数的修正,把敏感器的圆盘模型和三维模型推广到了其他轨道高度下. 相似文献
149.
测量并分析计算了角分辨紫外光电子谱仪的电子能量分析器的聚焦特性 ,分析计算了紫外光斜入射时光电信号的校正因子。结果表明 :偏离分析器聚焦中心 β角的光电子被分析器接收的几率为高斯函数exp( - β2 /β0 2 ) ,且 β0 =3.5° ;斜入射光电信号的校正因子是光入射角α的函数且大于cosα 相似文献
150.
R. M. Suleiman J.L. Kohl A. V. Panasyuk A. Ciaravella S.R. Cranmer L.D. Gardner R. Frazin R. Hauck P.L. Smith G. Noci 《Space Science Reviews》1999,87(1-2):327-330
The Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO) has been used to measure
spectral line profiles for H I Lyα in the south polar coronal hole at projected heliocentric heights from 3.5 to 6.0 R⊙ during 1998 January 5–11. Observations from 1.5 to 2.5 R⊙ were made for comparison. The H I Lyα profile is the only one observable with UVCS above 3.5 R⊙ in coronal holes. Within this region the outflowing coronal plasma becomes nearly collisionless and the ionization balance
is believed to become frozen.
In this paper, the 1/e half widths of the coronal velocity distributions are provided for the observed heights. The velocity
distributions include all motions contributing to the velocities along the line of sight (LOS). The observations have been
corrected for instrumental effects and interplanetary H I Lyα. The half widths were found to increase with projected heliographic
height from 1.5 to 2.5 R⊙ and decrease with height from 3.5 to 5 R⊙.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献