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1.
本文初步对比分析了昆明大气探空资料与大气视宁度观测资料之间的相关关系。结果表明,它们之间有着明显的关系和规律,但关系式的确立还需更多的资料分析才能确定。  相似文献   

2.
本文初步对比分析了昆明大气探空资料与大气视宁度观测资料之间的相关关系。结果表明,它们之间有着明显的关系和规律,但关系式的确立还需更多的资料分析才能确定。  相似文献   

3.
本文对呈现缺脉冲现象的脉冲星进行了统计分析,发现缺脉冲百分率NF与脉冲等值宽度We有更显著的相关关系,即比Biggs得到的NF-P和NF-α关系相关程度更高,利用Filippenko和Radhakrishnan模型,本文推导出NF的近似表达式,解释了上述统计结果。虽然缺脉冲现象总体上与年龄相关不大,即年龄大不是出现缺脉冲的必要条件,但缺脉冲现象显著的脉冲星确实分布在射电辐射的截止线附近,组成了一条和截止线近似平行的直线,反映了这类脉冲星的确处于老年阶段。本文对产生缺脉冲的原因作了简要的讨论。  相似文献   

4.
对3个超级活动区(大的δ型黑子群)NOAA 5395、6659、6891中的电流分布作了系统计算;利用已发表的计算方法,首次用于实际活动区的水平电流分布;给出了电流与耀斑核的关系。将这种关系分为两类:密切相关和准相关,并同时给出了统计结果。结果显示:1)对于垂直电流和水平电流来说,密切相关率分别是29%和10%,准相关率分别是50%和30%;2)有些耀斑核与两种电流都相关,而大多数只与其中一种相关;3)与两种电流都不相关的耀斑核只占6%左右;4)两种电流起互补作用,因而对于预报耀斑具有一定的作用。通过分析还发现,磁场剪切强的地方相应于强的垂直电流,而磁中性线附近纵向磁场梯度大的地方相应于强的水平电流。  相似文献   

5.
本文统计了1990年1月至8月S.G,D〔15〕发表的8800MHz太阳射电辐射事件、Hα耀斑和软X射线事件。8800MHz射电事件与耀斑相关率达83.1%,文章还给出了云南天文台米波射电事件与Hα耀斑的统计相关结果,并于Boulder的结果作了比较,详细分折了它们之间的关系。  相似文献   

6.
高能粒子流对地震活动的可能调制   总被引:10,自引:2,他引:8  
把地球作为一个开放系统,本文分析了不同地域范围的地震活动和太阳活动的关系,发现不同地域的地震活动也存在着一个大约11年的周期,这个周期可能与太阳活动的11年左右周期有关,但地震周期的峰值对应于太阳活动的下降段。它们的关系是负相关关系,本文进一步着重分析了地震活动与高速太阳风粒子流和宇宙线高能粒子流的关系,发现它们之间存在着一信信度水平很高的正相关,这样,我们可以推测太阳活动可能是通过调制到达地球的  相似文献   

7.
把地球作为一个开放系统,本文分析了不同地域范围的地震活动和太阳活动的关系,发现不同地域的地震活动也存在着一个大约11年的周期,这个周期可能与太阳活动的11年左右周期有关,但地震周期的峰值对应于太阳活动的下降段。它们的关系是负相关关系。本文进一步着重分析了地震活动与高速太阳风粒子流和宇宙线高能粒子流的关系,发现它们之间存在着一个信度水平很高的正相关。这样,我们可以推测太阳活动可能是通过调制到达地球的高能粒子流进而调制地震活动的。  相似文献   

8.
俞志尧 《天文学报》2005,46(2):145-150
在银河系中,超新星遗迹的射电巡视揭示了19个伴有OH1720MHz脉泽发射的超新星遗迹.在从超新星遗迹膨胀到分子云的激波波面的后面产生了这一类不寻常的脉泽源.这个模型的重要点是从超新星遗迹来的X射线促使产生OH分子.研究伴有OH1720MHz脉泽发射的混合形态超新星遗迹的X射线特征是很重要的.研究了这19个伴有OH1720MHz脉泽发射的混合形态超新星遗迹的X射线特征.得到了这些源的X射线物理参数之间的一些相关关系和反相关关系.X射线电离率ζ与θ、D、r、r^2等物理量均不相关,而与Lx之间存在着正相关关系.另外超新星遗迹的X射线光度与相伴的OH1720MHz脉泽的最弱的束流量密度之间存在着紧密的正相关关系.这些都说明从超新星遗迹来的X射线发射足够在激波波阵面后面分解水分子并产生OH1720MHz脉泽.  相似文献   

9.
提供一个基于光变曲线的长γ暴光度的估计量.对BASTE记录到的12个已知红移的γ暴,利用时域上的时变分析方法计算了各暴的功率密度谱,用功率密度的峰值P表征光变曲线变化的剧烈程度.通过拟合发现在共动坐标系P与γ暴的各向同性峰值光度L之间存在着相关关系.这是继Norris等和Reichart等发现时间延迟与光度、变化率与光度的相关性之后又一个γ暴时变特征量与其光度之间的相关关系.  相似文献   

10.
Blazar 的X射线谱性质   总被引:1,自引:0,他引:1  
从Donato文献中选择了一个含有69个Blazar的样本,样本中每个源有多个X射线辐射流量数据,用该样本研究了流量密度和谱指数之间的关系,以及研究了三类源(HBL,LBL,FSRQ)的红移和谱指数的分布。结果表明:对于HBLs,谱指数和流量密度之间有一个较好的反相关关系存在,而对于LBLs和FSRQs却没有相关。因此认为HBL的X射线是同步辐射所致,而LBL和FSRQ的X射线辐射较为复杂可能是同步自康普顿过程导致。HBL显示软X射线谱,而FSRQ显示硬X射线谱,LBL居中。在谱图中HBL位于近端,rSRQ位于远端,LBL居中。  相似文献   

11.
Some statements recently published on the coronal structure related to type III bursts are discussed. The indirect approach based upon computed coronal magnetic field, as proposed by Kuiper (1973), is examined; it is concluded that some doubt exists about the suitability of this method. The problem of the relationship between the existence of filaments inside an active center and type III bursts production is analysed: considering the respective locations of flaring sites and filaments as well as their place inside the magnetic network of the active center, one cannot deduce any evidence of type III inhibition by filaments. There is no direct conclusive evidence of the association of type III's with known coronal structures. Some observations suggest that at least in some cases, the coronal streamers are involved.  相似文献   

12.
The longitudinal distribution of coronal holes has been analyzed for the time interval 1976–2002. Coronal holes don't seem to be randomly distributed. The cluster structure has been revealed in the time—space organization of coronal hole distribution. The complexity and lifetime of clusters depend on the solar cycle phase. The comparison of active region and coronal hole cluster structures shows that some coronal hole clusters as well as active region ones occur almost simultaneously in both hemispheres, some clusters in the north or in the south hemisphere only. Some coronal hole clusters coincide with the active region clusters and some do not coincide. They reflect the large-scale solar magnetic field distribution.  相似文献   

13.
将冕环电流按成因分成三种类型:对流电流、感应电流和自举电流,并分别进行了讨论。将tokamak等离子体中的自举电流的概念引入到冕环中,初步分析表明在部分冕环中也可能产生可观的自举电流。这种电流的存在将对冕环的稳定性将产生重要的影响。  相似文献   

14.
A three-dimensional coronal magnetic field is reconstructed for the NOAA active region 11158 on 14 February 2011. A GPU-accelerated direct boundary integral equation (DBIE) method is implemented which is approximately 1000 times faster than the original DBIE used on solar non-linear force-free field modeling. Using the SDO/HMI vector magnetogram as the bottom boundary condition, the reconstructed magnetic field lines are compared with the projected EUV loop structures as observed in the front-view (SDO/AIA) and the side-view (STEREO-A/B) images for the first time; they show very good agreement three-dimensionally. A quantitative comparison with some stereoscopically reconstructed coronal loops shows that the average misalignment angles in our model are at the same order as the state-of-the-art results obtained from reconstructed coronal loops. It is found that the observed coronal loop structures can be grouped into a number of closed and open field structures with some central bright coronal loop features around the polarity inversion line. The reconstructed highly sheared magnetic field lines agree very well with the low-lying sigmoidal filament along the polarity inversion line. This central low-lying magnetic field loop system must have played a key role in powering the flare. It should be noted that while a strand-like coronal feature along the polarity inversion line may be related to the filament, one cannot simply interpret all the coronal bright features along the polarity inversion line as manifestation of the filament without any stereoscopic information.  相似文献   

15.
Endeve  Eirik  Leer  Egil 《Solar physics》2001,200(1-2):235-250
In coronal holes the electron (proton) density is low, and heating of the proton gas produces a rapidly increasing proton temperature in the inner corona. In models with a reasonable electron density in the upper transition region the proton gas becomes collisionless some 0.2 to 0.3 solar radii into the corona. In the collisionless region the proton heat flux is outwards, along the temperature gradient. The thermal coupling to electrons is weak in coronal holes, so the heat flux into the transition region is too small to supply the energy needed to heat the solar wind plasma to coronal temperatures. Our model studies indicate that in models with proton heating the inward heat conduction may be so inefficient that some of the energy flux must be deposited in the transition region to produce the proton fluxes that are observed in the solar wind. If we allow for coronal electron heating, the energy that is needed in the transition region to heat the solar wind to coronal temperatures, may be supplied by heat conduction from the corona.  相似文献   

16.
Kenneth P. Dere 《Solar physics》1982,75(1-2):189-203
XUV spectroheliograms of 2 active regions are studied. The images are due to lines emitted at temperatures between 8 x 104 K and 2 x 106 K and thus are indicative of transition region and coronal structures. The hot coronal lines are formed solely in loop structures which connect regions of opposite photospheric magnetic polarity but are not observed over sunspots. Transition region lines are emitted in plages overlying regions of intense photospheric magnetic field and in loops or loop-segments connecting such regions. The hot coronal loops are supported hydrostatically while only some of the transition zone loops are. The coronal and transition zone loops are distinctly separated and are not coaxial. A comparison of direct measurements of electron densities using density sensitive line ratios with indirect measurements using emission measures and path lengths shows the existence of fine structures of less than a second of arc in transition region loops. From a similar analysis, hot coronal loops do not have any fine structure below about 2 seconds of arc.  相似文献   

17.
日冕中冕环的无衰减横向振荡(简称无衰减振荡)自2012年被发现以来,受到了广泛的关注.无衰减振荡具有在日冕中广泛存在以及振幅无明显变小的特性,使之在解释日冕加热和冕震学诊断上都具有相当的潜力.总结了日冕中无衰减振荡的研究进展,包括观测研究得到的一系列结果、提出的理论和数值模型以及基于无衰减振荡进行冕震学诊断的一些尝试,并且展望了未来可以进一步开展的研究.  相似文献   

18.
在快速粒子流持续注入的条件下,日冕磁流管中离子迴旋不稳定性所引起的快速粒子流演化过程与电子加速过程可以分别考虑.本文详细给出被加速电子的能谱和流强的定量表达式,并讨论这种不稳定性引起的加速过程的一些特性.  相似文献   

19.
Coronal holes (CH) emit significantly less at coronal temperatures than quiet-Sun regions (QS), but can hardly be distinguished in most chromospheric and lower transition region lines. A key quantity for the understanding of this phenomenon is the magnetic field. We use data from SOHO/MDI to reconstruct the magnetic field in coronal holes and the quiet Sun with the help of a potential magnetic model. Starting from a regular grid on the solar surface we then trace field lines, which provide the overall geometry of the 3D magnetic field structure. We distinguish between open and closed field lines, with the closed field lines being assumed to represent magnetic loops. We then try to compute some properties of coronal loops. The loops in the coronal holes (CH) are found to be on average flatter than in the QS. High and long closed loops are extremely rare, whereas short and low-lying loops are almost as abundant in coronal holes as in the quiet Sun. When interpreted in the light of loop scaling laws this result suggests an explanation for the relatively strong chromospheric and transition region emission (many low-lying, short loops), but the weak coronal emission (few high and long loops) in coronal holes. In spite of this contrast our calculations also suggest that a significant fraction of the cool emission in CHs comes from the open flux regions. Despite these insights provided by the magnetic field line statistics further work is needed to obtain a definite answer to the question if loop statistics explain the differences between coronal holes and the quiet Sun.  相似文献   

20.
Mavromichalaki  H.  Plainaki  C.  Zouganelis  I.  Petropoulos  B. 《Solar physics》2003,218(1-2):63-78
Global changes of the solar activity can be expressed by the coronal index that is based upon the total irradiance of the coronal 530.3 nm green line from observations at five stations. Daily mean values of the coronal index of solar activity and other well-correlated solar indices are analyzed for the period 1966–1998 covering over three solar cycles. The significant correlation of this index with the sunspot number and the solar flare index have led to an analytical expression which can reproduce the coronal index of solar activity as a function of these parameters. This expression explains well the existence of the two maxima during the solar cycles taking into account the evolution of the magnetic field that can be expressed by some sinusoidal terms during solar maxima and minima. The accuracy between observed and calculated values of the coronal index on a daily basis reaches the value of 71%. It is concluded that the representative character of the coronal index is preserved even when using daily data and can therefore allow us to study long-term, intermediate and short-term variations for the Sun as a star, in association with different periodical solar–terrestrial phenomena useful for space weather studies.  相似文献   

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