排序方式: 共有17条查询结果,搜索用时 15 毫秒
11.
Theapplicationofmicrowaveremotesensingtechnologyinrock mechanicsNai-GuangGENG(耿乃光);Zheng-FangFAN(樊正芳);Quan-QuanJI(籍全权);Cheng-... 相似文献
12.
Chang-Hui Rao Wen-Han Jiang Cheng Fang Ning Ling Wei-Chao Zhou Ming-De Ding Xue-Jun Zhang Dong-Hong Chen Mei Li Xiu-Fa Gao Tian MiAdaptive Optics Lab. Institute of Optics Electronics Chinese Academy of Sciences P. O. Box Chengdu Astronomy Department Nanjing University Nanjing 《中国天文和天体物理学报》2003,3(6):576-586
13.
14.
As one of the most violent activities in the solar atmosphere,white-light flares(WLFs)are generally known for their enhanced white-light(or continuum)emission,which primarily originates in the solar lower atmosphere.However,we know little about how white-light emission is produced.In this study,we aim to investigate the response of the continua at 3600?and 4250?and also the Hαand Lyαlines during WLFs modeled using radiative hydrodynamic simulations.We take non-thermal electron beams as the energy source for the WLFs in two different initial atmospheres and vary their parameters.Our results show that the model with non-thermal electron beam heating clearly shows enhancements in the continua at 3600?and 4250?as well as in the Hαand Lyαlines.A larger electron beam flux,a smaller spectral index,or an initial penumbral atmosphere leads to a stronger emission increase at 3600?,4250?and in the Hαline.The Lyαline,however,is more obviously enhanced in a quiet-Sun initial atmosphere with a larger electron beam spectral index.It is also notable that the continua at 3600?and 4250?and the Hαline exhibit a dimming at the start of heating and reach their peak emissions after the peak time of the heating function,while the Lyαline does not show such behaviors.These results can serve as a reference for the analysis of future WLF observations. 相似文献
15.
YingLiu Ming-DeDing 《中国天文和天体物理学报》2002,2(3):277-286
The line profiles of Hα in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion technique to extract the probability distribution of the line-of-sight velocity in the flare. There exist some differences between the velocity distributions deduced from Hα and from CaⅡ λ8542, which may be because the two lines depend differently on the temperature and velocity. Since the loop density is high, we obtain a rather short cooling time (several tens of seconds) from the hot X-ray loops to the cool loops visible in Hα. Possible origins of the large scale motions are discussed. 相似文献
16.
With an extensive analysis,we study the temporal evolution of magnetic flux during three successive M-class flares in two adjacent active regions:NOAA 10039 and 10044.The primary data are full disk longitudinal magnetograms observed by SOHO/MDI.All three flares are observed to be accompanied by magnetic flux changes.The changes occurred immediately or within 1 ~ 10 minutes after the starting time of the flares,indicating that the changes are obvious consequences of the solar flares.Although changes in many ... 相似文献
17.
Zong-Jun Ning Ming-De Ding Department of Astronomy Nanjing University Nanjing Purple Mountain Observatory Chinese Academy of Sciences Nanjing 《中国天文和天体物理学报》2005,5(3):273-284
We analyze oscillation behaviours in chromospheric internetwork regions using spectral observations of the CⅡ1334 A line obtained with the Solar Ultraviolet Measurements of Emitted Radiation spectrograph (SUMER) aboard Solar and Heliospheric Observatory (SOHO). Three areas, 26 ×120arcsec2 each, at the various latitudes from the disk center to the north polar coronal hole, were rastered with a cadence of about 40-60 s in the solar minimum year. We obtained the time evolution of two-dimensional (2D) line intensity, continuum and line core shift. The continuum and the line shift show -3 min chromospheric oscillations in the internetwork regions underlying the coronal hole as well as at the disk center. We find that the CⅡ1334A line shift oscillates with an average speed of -1.7 km s-1, independent of the latitude, while its coherent scale decreases with latitude. On the other hand, the oscillation amplitude of the continuum around the 1334 A and the phase delay between the Doppler shift and continuum sli 相似文献