Statistical Study of the Geoeffectivity of Halo Coronal Mass Ejections Associated with X-Class Flares during Solar Cycles 23 and 24

By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ejections associated with X-class flares appear to be among the most energetic events in solar activity given the size of the flares, the speed of the CMEs and the intense geomagnetic storms they produce. Out of eighty-six (86) X-class halo CMEs, thirty-seven (37) or 43% are highly geoeffective;twenty-four (24) or approximately 28% are moderately geoeffective and twenty-five (25) or 29% are not geoeffective. Over the two solar cycles (1996 to 2019), 71% of storms were geoeffective and 29% were not. For solar cycle 23, about 78% of storms were geoeffective, while for solar cycle 24, about 56% were geoeffective. For the statistical study based on speed, 85 halo CMEs associated with X-class flares were selected because the CME of 6 December 2006 has no recorded speed value. For both solar cycles, 75.29% of the halo CMEs associated with X-class flares have a speed greater than 1000 km/s. The study showed that 42.18% of halo (X) CMEs with speeds above 1000 km/s could cause intense geomagnetic disturbances. These results show the contribution (in terms of speed) of each class of halo (X) CMEs to the perturbation of the Earth’s magnetic field. Coronal mass ejections then become one of the key indicators of solar activity, especially as they affect the Earth.

LyαEmission Enhancement Associated with Soft X-Ray Microflares

Lyα(Lyα,1216 A)is the strongest emission line in the solar ultraviolet spectrum.In the present work,we obtained a Lyαenhancement catalog covering flares larger than B1 class from the GOES/EUVS data during 2010-2016.We focused on the 242 B-class events which are less investigated,however,show non-negligible Lyαemission enhancement.We found that on average the Lyαpeak of B-class flares is 0.85%stronger than the background.For the flare energetics,it is found that the weaker the soft X-ray(SXR)flare,the larger the ratio of the radiated energy in Lyαto SXR.Using the RHESSI data and multi-wavelength observations taken by SDO-AIA,we diagnose the thermal and non-thermal properties of several flares.Three case studies show that the coincidence of the Lyαpeak with the SXR time-derivative peak is not a sufficient condition of the nonthermal property of a Lyαmicroflare.The Lyαenhancement in the microflares may be caused by the nonthermal electron beams or/and thermal conduction.However for typeⅢevents,we found that the delay of the Lyαpeak with respect to the SXR peak can be attributed to either the Lyαemission from a filament erupted or the cooling of the thermal plasma in flare loops.Furthermore,interestingly the Lyαemission from filaments can not only occur in the decay phase of the flare,but also in the preflare phase.In this case,the Lyαemission was originated from an erupted filament which probably initiated the flare.

New Cases of Superflares on Slowly Rotating Solar-type Stars and Large Amplitude Superflares in G-and M-type Main Sequence Stars

In our previous work,we searched for superflares on different types of stars while focusing on G-type dwarfs using entire Kepler data to study statistical properties of the occurrence rate of superflares.Using these new data,as a byproduct,we found 14 cases of superflare detection on 13 slowly rotating Sun-like stars with rotation periods of24.5–44 days.This result supports the earlier conclusion by others that the Sun may possibly undergo a surprise superflare.Moreover,we found 12 and seven new cases of detection of exceptionally large amplitude superflares on six and four main sequence stars of G-and M-type,respectively.No large-amplitude flares were detected in A,F or K main sequence stars.Here we present preliminary analysis of these cases.The superflare detection,i.e.,an estimation of flare energy,is based on a more accurate method compared to previous studies.We fit an exponential decay function to flare light curves and study the relation between e-folding decay time,τ,versus flare amplitude and flare energy.We find that for slowly rotating Sun-like stars,large values ofτcorrespond to small flare energies and small values ofτcorrespond to high flare energies considered.Similarly,τis large for small flare amplitudes andτis small for large amplitudes considered.However,there is no clear relation between these parameters for large amplitude superflares in the main sequence G-and M-type stars,as we could not establish clear functional dependence between the parameters via standard fitting algorithms.

A Statistical Study of Rapid Sunspot Structure Change Associated with Flares

We reported recently some rapid changes of sunspot structure in white-light （WL） associated with major flares. We extend the study to smaller events and present here results of a statistical study of this phenomenon. In total, we investigate 403 events from 1998 May 9 to 2004 July 17, including 40 X-class, 174 M-class, and 189 C-class flares. By monitoring the structure of the flaring active regions using the WL observations from the Transition Region and Coronal Explorer （TRACE）, we find that segments in the outer sunspot structure decayed rapidly right after many flares; and that, on the other hand, the central part of sunspots near the flare-associated magnetic neutral line became darkened. These rapid and permanent changes are evidenced in the time profiles of WL mean intensity and are not likely resulted from the flare emissions. Our study further shows that the outer sunspot structure decay as well as the central structure darkening are more likely to be detected in larger solar flares. For X-class flares, over 40% events show distinct sunspot structure change. For M- and C-class flares, this percentage drops to 17% and 10%, respectively. The results of this statistical study support our previously proposed reconnection picture, i.e., the flare-related magnetic fields evolve from a highly inclined to a more vertical configuration.

The relationships of solar flares with both sunspot and geomagnetic activity

The relationships between solar flare parameters （total importance, time duration, flare index, and flux） and sunspot activity （R z ） as well as those between geomagnetic activity （aa index） and the flare parameters can be well described by an integral response model with the response time scales of about 8 and 13 months, respectively. Compared with linear relationships, the correlation coefficients of the flare parameters with R z , of aa with the flare parameters, and of aa with R z based on this model have increased about 6%, 17%, and 47% on average, respectively. The time delays between the flare parameters with respect to R z , aa to the flare parameters, and aa to R z at their peaks in a solar cycle can be predicted in part by this model （82%, 47%, and 78%, respectively）. These results may be further improved when using a cosine filter with a wider window. It implies that solar flares are related to the accumulation of solar magnetic energy in the past through a time decay factor. The above results may help us to understand the mechanism of solar flares and to improve the prediction of the solar flares.

Change Ratios of Magnetic Helicity and Magnetic Free Energy During Major Solar Flares

Magnetic helicity is an important concept in solar physics,with a number of theoretical statements pointing out the important role of magnetic helicity in solar flares and coronal mass ejections(CMEs).Here we construct a sample of 47 solar flares,which contains 18 no-CME-associated confined flares and 29 CME-associated eruptive flares.We calculate the change ratios of magnetic helicity and magnetic free energy before and after these 47 flares.Our calculations show that the change ratios of magnetic helicity and magnetic free energy show distinct different distributions in confined flares and eruptive flares.The median value of the change ratios of magnetic helicity in confined flares is-0.8%,while this number is-14.5%for eruptive flares.For the magnetic free energy,the median value of the change ratios is-4.3%for confined flares,whereas this number is-14.6%for eruptive flares.This statistical result,using observational data,is well consistent with the theoretical understandings that magnetic helicity is approximately conserved in the magnetic reconnection,as shown by confined flares,and the CMEs take away magnetic helicity from the corona,as shown by eruptive flares.

The Formation and Evolution of the Sun and the Source of Star Energy as Well as the Sunspots and Flares of the Sun

Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core temperature of the gas cloud rises to 10million K, the thermonuclear reaction of hydrogen fusion into helium is ignited, then the Sun become a star;once the hydrogen in thecore is exhausted, the life of the star will end. But the limited hydrogen element obviously cannot satisfy such a long-termthermonuclear reaction, in order to sustain long-term thermonuclear reactions, a steady stream of fuel must be obtained from space.So the existing hypothesis about the formation and evolution of the Solar System has serious defects. Thus the author has studied theformation of the Moon, the Earth and the Sun, and discovered the formation of the Sun and the real source of star energy. The authorcould also explain many solar activity phenomena such as sunspots, flares, prominences, etc.

Martian Thermosphere Response to Solar Flares:MAVEN NGIMS Observations

The solar flare is a sudden eruptive solar phenomenon with significant enhancements in solar X-ray and Extreme Ultraviolet radiations,resulting in large amounts of energy being injected into the planetary atmosphere.Case studies have been extensively presented to analyze the effect of extremely large flares on the Martian upper atmosphere,but the general features of the Martian thermospheric response to flares are still poorly understood.In this work,we select 12 intense solar flares that occurred between 2015 and 2017 and investigate the densities and compositional variations of the dayside Martian thermosphere to these flares with the aid of the measurements made by the Mars Atmosphere and Volatile EvolutioN.The statistical studies indicate that the responses of the Martian thermosphere to flares are complicated that both the class of the flare and the wavelength of the enhanced radiation may have prominent influences on the thermal expansion of the atmosphere and the atmospheric photochemical reactions.

A Confined Two-peaked Solar Flare Observed by EAST and SDO

The solar flare is one of the most violent explosions,and can disturb the near-Earth space weather.Except for commonly single-peaked solar flares in soft X-ray,some special flares show intriguing a two-peak feature that is deserved much more attentions.Here,we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics Observatory.Before the flare,a magnetic flux rope(MFR)formed through partially tether-cutting reconnection between two sheared arches.The flare occurred after the MFR eruption that was confined by the overlying strong field.Interestingly,a small underlying filament immediately erupted,which was possibly destabilized by the flare ribbon.The successive eruptions were confirmed by the analysis of the emission measure and the reconnection fluxes.Therefore,we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.

Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429

We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading sunspot with positive magnetic polarity rotated counterclockwise.As expected,the rotation was significantly affected by the two flares.Magnetic transients induced by the flares were clearly evident in the sunspots with negative polarity.They were moving across the sunspots with speed of order 3-7 km s-1.Furthermore,the trend of magnetic flux evolution in these sunspots exhibited changes associated with the flares.These results may shed light on understanding the evolution of sunspots.

Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model

Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities.

Jovian Planet Influence on the Forcing of Sunspot Cycles

The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, Jupiter that has a nearly circular orbit. This has allowed relics of the early solar system formation to still be observable today. Since Jupiter orbits the Sun with a period of approximately 12 years, it has always been thought that this could be connected to the nearly 11-year periodic peak in the number of sunspots observed. In this paper, the Sun and planets are considered to be moving about a center of mass point as the different planets orbit the Sun. This is the action of gravity that holds the solar system together. The center of mass for the Jupiter-Sun system actually lies outside the Sun. The four gas giant planets dominate such effects and the four gas giant Jovian planets can be projected together to determine an effective distance from the Sun’s center. Taken together these effects do seem to function as a sunspot forcing factor with a periodicity very close to 11 years. These predictions are made without consideration of any details of what is happening in the interior of the Sun. From these estimates, sunspot cycle 25 will be expected to peak in about September-October of 2025. Sunspot cycle 26 should peak in the year March of 2037.

Variation in the Flaring Potential of Different Sunspot Groups During Different Phases of Solar Cycles 23 and 24

In this present study,we have analyzed different types of X-ray solar flares(C,M,and X classes)coming out from different classes of sunspot groups(SSGs).The data which we have taken under this study cover the duration of 24 yr from 1996 to 2019.During this,we observed a total of 15015 flares(8417 in SC-23 and 6598 in SC-24)emitted from a total of 33780 active regions(21746 in SC-23 and 12034 in SC-24)with sunspot only.We defined the flaring potential or flare-production potential as the ratio of the total number of flares produced from a particular type of SSG to the total number of the same-class SSGs observed on the solar surface.Here we studied yearly changes in the flaring potential of different McIntosh class groups of sunspots in different phases of SC-23 and 24.In addition,we investigated yearly variations in the potential of producing flares by different SSGs(A,B,C,D,E,F,and H)during different phases(ascending,maximum,descending,and minimum)of SC-23 and 24.These are our findings:(1)D,E,and F SSGs have the potential of producing flares≥8 times greater than A,B,C and H SSGs;(2)The larger and more complex D,E,and F SSGs produced nearly 80%of flares in SC-23 and 24;(3)The A,B,C and H SSGs,which are smaller and simpler,produced only 20%of flares in SC-23 and 24;(4)The biggest and most complex SSGs of F-class have flaring potential 1.996 and 3.443 per SSG in SC-23 and 24,respectively.(5)The potential for producing flares in each SSG is higher in SC-24 than in SC-23,although SC-24 is a weaker cycle than SC-23.(6)The alterations in the number of flares(C+M+X)show different time profiles than the alterations in sunspot numbers during SC-23 and 24,with several peaks.(7)The SSGs of C,D,E,and H-class have the highest flaring potential in the descending phase of both SC-23 and 24.(8)F-class SSGs have the highest flaring potential in the descending phase of SC-23 but also in the maximum phase of SC-24.

基于FLARESIM模拟的LNG接收站高架火炬设计选型研究

火炬系统是维护LNG接收站安全运行的重要设备。为了直观有效的掌握高架火炬热辐射对接收站内设施及周边环境的影响,评估火炬设置的合理性与安全性。在相关规范内容的基础上细化LNG接收站火炬系统处理能力的选型工况,其作为重要的输入条件,提高火炬设计规模及火炬系统设计的准确性,在此基础上进一步通过FLARESIM软件对高架火炬包括筒体尺寸、火炬头及火炬高度等进行模拟计算,在标准允许范围内有效识别并评估热辐射对接受点的影响,以确定高架火炬的设计参数及布置位置。一般说来,常规LNG接收站火炬泄放量最大组合工况为储罐漏热+大气压降低+控制阀失效或储罐漏热+大气压降低+卸船充装时的置换和闪蒸,并通过调整火炬位置及火炬筒高度可以满足热辐射的要求及气体扩散浓度要求。

Dark Galaxies, Sun-Earth-Moon Interaction, Tunguska Event—Explained by WUM

Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fact, an object the size of a galaxy, made entirely of dark matter. They found that the speed of the Earth’s rotation varies randomly each day. 115 years ago, the Tunguska Event was observed, and astronomers still do not have an explanation of It. Main results of the present article are: 1) Dark galaxies explained by the spinning of their Dark Matter Cores with the surface speed at equator less than the escape velocity. Their Rotational Fission is not happening. Extrasolar systems do not emerge;2) 21-cm Emission explained by the self-annihilation of Dark Matter particles XIONs (5.3 μeV);3) Sun-Earth-Moon Interaction explained by the influence of the Sun’s and the Moon’s magnetic field on the electrical currents of the charged Geomagma (the 660-km layer), and, as a result, the Earth’s daylength varies;4) Tunguska Event explained by a huge atmospheric explosion of the Superbolide, which was a stable Dark Matter Bubble before entering the Earth’s atmosphere.

Ensemble prediction model of solar proton events associated with solar flares and coronal mass ejections

An ensemble prediction model of solar proton events （SPEs）, combining the information of solar flares and coronal mass ejections （CMEs）, is built. In this model, solar flares are parameterized by the peak flux, the duration and the longitude. In addition, CMEs are parameterized by the width, the speed and the measurement position angle. The importance of each parameter for the occurrence of SPEs is estimated by the information gain ratio. We find that the CME width and speed are more informative than the flare’s peak flux and duration. As the physical mechanism of SPEs is not very clear, a hidden naive Bayes approach, which is a probability-based calculation method from the field of machine learning, is used to build the prediction model from the observational data. As is known, SPEs originate from solar flares and/or shock waves associated with CMEs. Hence, we first build two base prediction models using the properties of solar flares and CMEs, respectively. Then the outputs of these models are combined to generate the ensemble prediction model of SPEs. The ensemble prediction model incorporating the complementary information of solar flares and CMEs achieves better performance than each base prediction model taken separately.

海洋平台FLARESIM火炬模拟计算方法探讨

FLARESIM软件是一款用于火炬分析与设计的专业软件,它可以分析火炬泄放时产生的热辐射、温度和噪音,同时也可以进行可燃气体的扩散分析。作为火炬模拟与计算的专业软件,FLARESIM越来越多地应用于石油、石化行业。分析了几种常用的计算方法并以某海上平台为例,运用FLARESIM软件进行模拟,着重比较FLaresim API与Mixed方法对模拟结果的影响,研发了一套适用于一般项目的工程模拟方法。

The causality between the rapid rotation of a sunspot and an X3.4 flare

Using multi-wavelength data of Hinode, the rapid rotation of a sunspot in active region NOAA 10930 is studied in detail. We found extraordinary counterclockwise rotation of the sunspot with positive polarity before an X3.4 flare. From a series of vector magnetograms, it is found that magnetic force lines are highly sheared along the neutral line accompanying the sunspot rotation. Furthermore, it is also found that sheared loops and an inverse S-shaped magnetic loop in the corona formed gradually after the sunspot rotation. The X3.4 flare can be reasonably regarded as a result of this movement. A detailed analysis provides evidence that sunspot rotation leads to magnetic field lines twisting in the photosphere. The twist is then transported into the corona and triggers flares.

Hepatic flares in chronic hepatitis C: Spontaneous exacerbation vs hepatotropic viruses superinfection

The hepatitis C virus(HCV)causes an acute infection that is frequently asymptomatic,but a spontaneous eradication of HCV infection occurs only in one-third of patients.The remaining two-thirds develop a chronic infection that,in most cases,shows an indolent course and a slow progression to the more advanced stagesof the illness.Nearly a quarter of cases with chronic hepatitis C(CHC)develop liver cirrhosis with or without hepatocellular carcinoma.The indolent course of the illness may be troubled by the occurrence of a hepatic flare,i.e.,a spontaneous acute exacerbation of CHC due to changes in the immune response,immunosuppression and subsequent restoration,and is characterized by an increase in serum aminotransferase values,a frequent deterioration in liver fibrosis and necroinflammation but also a high frequency of sustained viral response to pegylated interferon plus ribavirin treatment.A substantial increase in serum aminotransferase values during the clinical course of CHC may also be a consequence of a superinfection by other hepatotropic viruses,namely hepatitis B virus(HBV),HBV plus hepatitis D virus,hepatitis E virus,cytomegalovirus,particularly in geographical areas with high endemicity levels.The etiology of a hepatic flare in patients with CHC should always be defined to optimize follow-up procedures and clinical and therapeutic decisions.

Double hard X-ray peaks in RHESSI flares as evidence of chromospheric evaporation and implications for modifying the Neupert effect

Among the RHESSI flare samples, we concentrated on a kind of flare that presents two successive peaks （that is, it presents both an impulsive phase and a gradual phase） in 12 - 25 keV light curves. Taking the C1.4 flare on 2002 August 12 as an example, we studied the light curves, spectra, and images in detail. Making full use of the capabilities of RHESSI, we showed some evidence to support the expected causal relationship between these two peaks; the first peak is mainly nonthermal, while the second peak is mainly thermal; the energy carried by nonthermal electrons during the first peak seems to be comparable to the thermal energy of the second peak. The morphologies of X-ray images and their evolutions provide additional evidence for this causality. We conclude that two such peaks in the 12 - 25 keV light curve are good evidence for the chromospheric evaporation. However, the maximum time of the second peak is later than the end time of the first peak, suggesting that for some events, a modification of the traditional Neupert effect could be necessary by inclusion of a time delay, which might be partly related to the filling of the loop by evaporated material.