日冕物质抛射—空间天气的扰动源

日冕物质抛射是引起空间天气扰动的重要起因＿本文对日冕物质抛射的一般参量和形态、它与其它太阳活动现象的关系、它在行星际空间的表现以及它导致的地球空间环境扰动的研究进展作了介绍和讨论     

Correlation between the parameters of coronal mass ejections and features of their propagation in the corona with the large-scale structure of the solar magnetic field

Correlation between the parameters of coronal mass ejections (CMEs) that are detected on the LASCO coronographs and are associated with eruptive prominences and the distances of CME axes from the coronal streamer belt has been analyzed. The deviations of CME trajectories from the radial direction have been investigated.     

Statistical Studies of Coronal Mass Ejections and Coronal Holes

Statistical studies of coronal mass ejections (CMEs) and coronal holes (CHs) are reviewed. The work summarizes the historical and current results of statistical studies of CMEs and CHs and their parameters that have been obtained by various authors who considered these phenomena as independent manifestations of solar activity, as well as their mutual effect on geomagnetic activity, based on both ground and space observations.     

Simulation of Coronal Mass Ejection Propagation Based on Data from Ground-Based Patrol Observations

Geomagnetism and Aeronomy - We present a model for the propagation of coronal mass ejections (CMEs) based on the interaction of CMEs with the solar wind through aerodynamic drag. The parameters of...     

Method for determining the parameters of full halo coronal mass ejections

A method for determining the parameters of halo-type coronal mass ejections (full halo CMEs)—direction of motion, angular size, CME velocity along the Sun-Earth axis, etc.—has been proposed and tested. The method is based on the found empirical dependence between the angular sizes of CMEs located near the sky plane and angular sizes of associated eruptive prominences or post-eruptive arcades as well as on the relationships between the halo CME parameters derived in a simple geometrical CME model. Using this method and the SOHO/LASCO C3 and SOHO/EIT data, the parameters of 33 full halo CMEs have been determined. It is concluded that (1) the trajectories of all considered full halo CMEs deviate with recession of the CME front to R _F > (2–5)R ₀ toward the Sun-Earth axis; (2) the majority of full halo CMEs recorded by LASCO C3 coronagraphs have relatively large angular sizes, 2α > 60°.     

Spectral-temporal peculiarities of the microwave emission preceding geoeffective coronal mass ejections

Data on the complex of wave and spectral phenomena in the sporadic microwave emission that are associated with the formation and initial propagation of coronal mass ejections (CMEs) in the solar atmosphere are presented. Their characteristic time interval extends from 2–3 days preceding the event to the time of CME recording on coronagraphs.     

Analyzing the Variation of Lyapunov Exponents of the Time Derivatives of the Horizontal Geomagnetic Field during the Geomagnetic Storm

Geomagnetism and Aeronomy - The geomagnetic disturbance associated with coronal mass ejections (CMEs) of September 8, 2017 was evaluated using the time derivatives of the horizontal geomagnetic...     

Geoefficiency of solar eruptive events

The sources of geomagnetic disturbances during 1999–2003 are discussed. The relation between geomagnetic activity and the rate of coronal mass ejections (CMEs), their parameters, and the dynamics of solar photospheric magnetic fields is considered. It is shown that during the reorganization of unipolar regions of the photospheric magnetic field, the number of CMEs increases and their parameters change. The geomagnetic disturbance level also increases in these periods.     

New Approaches to the Identification of Sources and the Onset of Stealth Coronal Mass Ejections

Geomagnetism and Aeronomy - New approaches to the identification of sources and the onset of stealth coronal mass ejections (CMEs) are discussed based on the stealth CME of July 7, 2012. It is...     

Features of the Behavior of Microwave and Ultraviolet Emission of Solar Active Regions in Relation to Eruptive and Confined Flares

Geomagnetism and Aeronomy - In this study, a comparative analysis was carried out on the preflare and flare conditions for six flares accompanied by coronal mass ejections (CMEs) and five events...     

Search for the Relationship between the Velocity of a Coronal Mass Ejection and the Decay Rate of the Magnetic Field in the Region of Mass Emission Generation

Geomagnetism and Aeronomy - In this paper, we search for the relationship between the Vlin linear projection velocity and the Vss velocity in the 3D space of coronal mass ejections (CMEs) recorded...     

Comparison of Features of the Generation of Coronal Mass Ejections with Variable Velocity in the Field of View of LASCO Coronagraphs

Geomagnetism and Aeronomy - This paper compares features of the generation of coronal mass ejections (CMEs) with the lowest, intermediate, and highest velocities in the field of view of LASCO C2...     

Regularities in the Formation of Coronal Mass Ejections Associated and not Associated with Type II Radio Bursts

Geomagnetism and Aeronomy - Regularities in the formation of coronal mass ejections (CMEs) associated (Radio Loud, RL CME) and not associated (Radio Quiet, RQ CME) with type II radio bursts (RBIIs)...     

Index of the Long-Term Influence of Sporadic Solar Activity on Cosmic Ray Modulation

Coronal mass ejections (CMEs) not only produce Forbush effects but contribute to long-term modulations of cosmic rays. That makes coronal ejections the main sporadic manifestations of the solar activity, which should be considered in modulation models. In this paper, a new version of the CME-index is proposed based on a comparison of the data from satellite coronographs with Forbush effects and long-term variations of cosmic rays.     

Initiation of CMEs: A review

Solar coronal mass ejections (CMEs) are a striking manifestation of solar activity seen in the solar corona, which bring out coronal plasma as well as magnetic flux into the interplanetary space and may cause strong interplanetary disturbances and geomagnetic storms. Understanding the initiation of CMEs and forecasting them are an important topic in both solar physics and geophysics. In this paper, we review recent progresses in research on the initiation of CMEs. Several initiation mechanisms and models are discussed. No single model/simulation is able to explain all the observations available to date, even for a single event.     

Flares,ejections, proton events

Statistical analysis is performed for the relationship of coronal mass ejections (CMEs) and X-ray flares with the fluxes of solar protons with energies >10 and >100 MeV observed near the Earth. The basis for this analysis was the events that took place in 1976–2015, for which there are reliable observations of X-ray flares on GOES satellites and CME observations with SOHO/LASCO coronagraphs. A fairly good correlation has been revealed between the magnitude of proton enhancements and the power and duration of flares, as well as the initial CME speed. The statistics do not give a clear advantage either to CMEs or the flares concerning their relation with proton events, but the characteristics of the flares and ejections complement each other well and are reasonable to use together in the forecast models. Numerical dependences are obtained that allow estimation of the proton fluxes to the Earth expected from solar observations; possibilities for improving the model are discussed.     

24th Cycle of Solar Activity: Geoefficiency of Flares

Geomagnetism and Aeronomy - Various aspects of the of geoefficiency of solar-activity phenomena, such as flares and coronal mass ejections (CMEs), are considered. The number of geoefficient events...     

Structural and dynamic features of geoeffective coronal ejections

The structure and physical conditions in 104 coronal mass ejections (CMEs) with a clear-cut leading shock front have been considered using satellite data for 1996–2008. In 99% of cases, the action of increased shock front dynamic pressure on the Earth’s magnetosphere resulted in the origination of geomagnetic storms with sudden commencement.     

Early life of coronal mass ejections

Coronal mass ejections (CMEs) are large-scale magnetized plasma structures ejected from closed magnetic field regions of the Sun. White light coronagraphic observations from ground and space have provided extensive information on CMEs in the outer corona. However, our understanding of the solar origin and early life of CMEs is still in an elementary stage because of lack of adequate observations. Recent space missions such as Yohkoh and Solar and Heliospheric Observatory (SOHO) and ground-based radioheliographs at Nobeyama and Nancay have accumulated a wealth of information on the manifestations of CMEs near the solar surface. We review some of these observations in an attempt to relate them to what we already know about CMEs. Our discussion relies heavily on non-coronagraphic data combined with coronagraphic data. Specifically, we discuss the following aspects of CMEs: (i) coronal dimming and global disk signatures, (ii) non-radial propagation during the early phase, (iii) Photospheric magnetic field changes during CMEs, and (iv) acceleration of fast CMEs. The relative positions and evolution of coronal dimming, arcade formation, prominence eruption will be discussed using specific events. The magnitude and spatial extent of CME acceleration may be an important parameter that distinguishes fast and slow CMEs.