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11.
We present near-infrared broad-band JHK ' images of the southern massive star-forming region G333.6−0.2. The slope of the K -luminosity function towards the region  (0.24 ± 0.01)  is considered to be equivalent to that expected for main-sequence stars in the solar neighbourhood. Point sources with their ( H − K ) colour greater than 1 are more likely to be located in extended emission and it is suggested that these objects are physically associated with the H  ii region.  相似文献   
12.
Presented are new images of supernova remnants G114.3 0.3, G116.5 1.1 and G116.9 0.2 (CTB 1) at 408 MHz from the Canadian Galactic Plane Survey (CGPS). We also use the 1420 MHz images from the CGPS in a study of their 408-1420 MHz spectral indices. The flux densities at 408 MHz and 1420 MHz, corrected for flux densities from compact sources within the SNRs, are 12±6 Jy and 9.8±0.8 Jy for Gl 14.3 0.3,15.0±1.5 Jy and 10.6±0.6 Jy for G116.5 1.1, 15.0±1.5 Jy and 8.1±0.4 Jy for G116.9±0.2. The integrated flux density-based spectral indices (Sv∝v-α) areα=0.16±0.41, 0.28±0.09 and 0.49±0.09 for G114.3 0.3, G116.5 1.1 and G116.9 0.2, respectively. Their T-T plot-based spectral indices are 0.68±0.48, 0.28±0.15, and 0.48±0.04, in agreement with the integrated flux density-based spectral indices. New flux densities are derived at 2695 MHz which are significantly larger than previous values. The new 408, 1420 and 2695 MHz flux densities and published values at other frequencies, where images are not available, are fitted after correcting for contributions from compact sources, to derive their multi-frequency spectral indices.  相似文献   
13.
We have observed two fields – Field I     ,     and Field II     ,     – with the Giant Metrewave Radio Telescope (GMRT) at 330 MHz. In the first field, we have studied the candidate supernova remnant (SNR) G3.1−0.6 and, based on its observed morphology, spectral index and polarization, confirmed it to be an SNR. We find this supernova to have a double ring appearance with a strip of emission on its western side passing through its centre.
We have discovered two extended curved objects in the second field, which appears to be part of a large shell-like structure. It is possibly the remains of an old supernova in the region. Three suspected SNRs, G356.3−0.3, G356.6+0.1 and G357.1−0.2, detected in the MOST 843-MHz survey of the GC region appear to be located on this shell-like structure. While both G356.3−0.3 and G356.6+0.1 seem to be parts of this shell, G357.1−0.2, which has a steeper spectrum above 1 GHz, could be a background SNR seen through the region. Our H  i absorption observation towards the candidate SNR G357.1−0.2 indicates that it is at a distance of more than 6 kpc from us.  相似文献   
14.
We present     spectropolarimetry, and 12- and 2-μm imaging polarimetry of the southern massive star-forming region G333.6−0.2. Spectro-polarimetry measurements show that the polarization observed towards the nebula contains a mixture of both absorptive and emissive polarizations. Model fitting to the spectra indicates that the temperature of the mid-infrared emitting dust grains is generally ∼200 K and the optical depth of the absorbing dust at 9.7 μm is ∼1.5. Fits are also made to the polarimetry spectra, which show a reasonably constant peak absorptive polarization (∼3.4 per cent at 43°) across the face of the H  ii region. This absorptive polarization position angle is consistent with that found by the 2-μm imaging polarimetry     and is most likely due to the Galactic magnetic field local to G333.6−0.2. When the absorptive polarization is subtracted from the 12-μm polarization image, the emissive polarization pattern that is intrinsic to the star-forming region is revealed. A probable magnetic field configuration implied by the intrinsic polarization suggests star formation initially influenced by the Galactic magnetic field which is eventually perturbed by the star formation process.  相似文献   
15.
大别造山带、东秦岭造山带和东昆仑造山带是中国中央山系的主要构成部分,每个造山带古老岩系的变质作用过程各具特色.大别山最古老岩系大别岩群于印支期陆内俯冲碰撞,发生了区域性的中偏高压区域变质作用,顺时针型pt轨迹上tmax和pmax近于同时达到,退变质轨迹段斜率陡,埋深后受构造驱动快速抬升到上中地壳.东秦岭最古老岩系秦岭岩群在晋宁期(约1.0Ga前)初始板块构造总背景下发生强烈的中压型碰撞变质作用,顺时针型pt轨迹上tmax在压力大幅度降低的过程中达到,反映弧陆碰撞增厚后深埋岩系受重力均衡抬升;至加里东期,秦岭岩群再次在板块构造的总背景下发生岛弧型变质,局部叠加中压型接触变质作用;晚海西以来北秦岭东段缺乏高于低角闪岩相条件的区域变质作用记录.东昆仑造山带最古老岩系于吕梁或早吕梁期发生中压碰撞区域变质,主体为角闪岩相,局部高角闪岩相-麻粒岩相条件,造山带剥露较浅使低压变质带得以良好保存.  相似文献   
16.
利用SH地震波(偏振化方向垂直入射面的横波)在地层界面反射系数的附加相角导出了SH波Goos-Hänchen效应所引起的横向偏移和横向偏移渡越时间,给出了Goos-Hänchen效应正常时差公式,讨论了Goos-Hänchen效应对反射SH波正常时差的影响,绘出了横向偏移、横向偏移渡越时间、Goos-Hänchen效应正常时差及Goos-Hänchen效应正常时差校正量曲线.数值算例表明:对掠入射波或入射角在临界角附近的入射波,SH反射波的横向偏移、横向偏移渡越时间非常大,Goos-Hänchen效应对正常时差会产生较大的测量误差,在其他角度的入射波,横向偏移(横向偏移渡越时间)与波长(周期)为同一个数量级.横向偏移效应对SH反射波的传播走时影响是不可忽略的,因此在实际的地震资料处理中应进行横向偏移效应误差校正.  相似文献   
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