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Mapping the magnetic field in the solar corona through magnetoseismology

Science China(Technological Sciences) 2020年第11期63卷 2357-2368页

作者： YANG ZiHao TIAN Hui TOMCZYK Steven MORTON Richard BAI XianYong SAMANTA Tanmoy CHEN YaJie School of Earth and Space Sciences Peking UniversityBeijing 100871China Key Laboratory of solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China High Altitude Observatory National Center for Atmospheric ResearchBoulderCO 80307USA Department of Mathematics Physics and Electrical EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK Department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Johns Hopkins University Applied Physics Laboratory LaurelMD 20723USA Max Planck Institute for solar System Research 37077 G¨ottingenGermany

Magnetoseismology,a technique of magnetic field diagnostics based on observations of magnetohydrodynamic(MHD)waves,has been widely used to estimate the field strengths of oscillating structures in the solar ***,previously magnetoseismology was mostly applied to occasionally occurring oscillation events,providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating *** restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the coronal Multi-channel Polarimeter(CoMP).Using several CoMP observations of the Fe xiii 1074.7 nm and 1079.8 nm spectral lines,we obtained maps of the plasma density and wave phase speed in the corona,which allow us to map both the strength and direction of the coronal magnetic field in the plane of *** also examined distributions of the electron density and magnetic field strength,and compared their variations with height in the quiet Sun and active *** measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere.

关键词： solar corona solar magnetic field waves magnetoseismology

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Dynamics of the charged particles released from a Sun-grazing comet in the solar corona

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Earth and Planetary Physics 2021年第3期5卷 232-238页

作者： ChuanPeng Hou JianSen He Lei Zhang Ying Wang Die Duan School of Earth and Space Sciences Peking UniversityBeijing 100871China Qian Xuesen Laboratory of Space Technology Beijing 100094China SIGMA Space Weather Group National Space Sciences CenterChinese Academy of SciencesBeijing 100190China

The sun-grazing comet C/2011 W3(Lovejoy)showed a distorted,unconventional tail morphology near its perihelion(1.2Rs).Based on the“solar corona and Inner Heliosphere”modeling result of the magnetic field and plasma dynamics in the solar corona,we use the Runge-Kutta method to simulate the moving trajectory of charged dust and ion particles released at different positions from the C/2011 W3 *** find that the dust particles near the sun,which are subject to a strong magnetic Lorentz force,travel differently from their counterparts distant from the sun,where the latter are mainly affected by the solar gravitational force and radiation *** to the simulation results,we propose that the magnetic mirror effect can rebound the charged dust particles back away from the sun and be regarded as one crucial cause of the dust-free zone *** find that ions mainly move along magnetic field lines at an acute angle to the comet's direction of *** cometary ions'movement direction was determined by the comet's velocity and the coronal magnetic field,which are responsible for the C/2011 W3’s unique comet tail shape near ***,the ion particles also experience perpendicular drift motion,mainly dominated by the electric field drift,which is similar to and can be used to approximate the solar wind's transverse velocity at its source region.

关键词： Sun-grazing comet cometary tail solar corona solar wind dust-free zone

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Observations of the solar corona during the total solar eclipse on 21 August 2017

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Earth and Planetary Physics 2017年第1期1卷 68-71页

作者： Hui Tian ZhongQuan Qu YaJie Chen LinHua Deng ZhengHua Huang Hao Li Yue Zhong Yu Liang JingWen Zhang YiGong Zhang BaoLi Lun XiangMing Cheng XiaoLi Yan ZhiKe Xue YuXin Xin ZhiMing Song YingJie Zhu Tanmoy Samanta School of Earth and Space Sciences Peking University Yunnan Observatories Chinese Academy of Sciences Shandong Provincial Key Laboratory of Optical Astronomy and solar-Terrestrial Environment Institute of Space Sciences Shandong University

The Sun’s tenuous outer atmosphere,the corona,emits only about one-millionth as much light as the solar *** ancient times the corona was observed by human beings only during total solar eclipses,when the strong emiss... 详细信息

关键词： solar corona solar eclipse solar magnetic fields coronal heating

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Thermodynamic Interpretation of Electron Density and Temperature Description in the solar corona

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Advances in Aerospace Science and Technology 2022年第3期7卷 146-174页

作者： Daniel B. Berdichevsky Jenny M. Rodríguez Gómez College Park MD USA IFIR/UNR-CONICET Rosario Sta Fé Argentina NASA Goddard Space Flight Center Greenbelt MD USA The Catholic University of America Washington D.C. USA

We reach a thermodynamic interpretation of the CODET model and its accurate electron density and temperature prediction, grounded on the physics of hydro magnetism in global equilibrium. The thermodynamic interpretation finds consistency with the model of a magneto-matter medium possessing a 3-D Langmuir structure. That medium is diamagnetic in the context of ideal magnetohydrodynamic (MHD). It is shown that this magneto-matter has unusual characteristics consistent with assuming that the low quiescent solar corona possesses a nature-state, non yet studied. It is further noticed that this is wholly consistent with the CODET model prediction of a polytropic anomalous index for the electron gas of the Sun’s corona. Constitutive properties are derived from this novel state of nature, like magnetic permeability properties and non-dispersive acoustic speed. This non-dispersive acoustic speed is also expected to predict the observed equilibration time for the 1.1 to 1.3R⊙ quiescent corona during the solar minimum from 2008 to 2009.

关键词： solar corona Density Temperature and Polytropic Anomalous Index

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Redshift Anomaly of the 2292 MHz Radio Signal Emitted by the Pioneer-6 Space Probe as Multiple Interactions with Photo-Ionized Electrons in the solar corona

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Journal of High Energy Physics, Gravitation and Cosmology 2021年第3期7卷 1107-1156页

作者： Alessandro Trinchera Independent Researcher Stuttgart Germany

This paper calculates the redshift of the 2292 MHz radio photon emitted by the Pioneer-6 space probe. The signal crossed the solar corona on the days close to the solar occultation between November and December 1968, the only ones for which scientific data are available, until it reached a terrestrial radio receiver. The specific study is based on a calculated orbital model of the Earth and Pioneer-6 system made on a scale of 1:100,000 by a CAD, on the New Tired Light theory adapted to the geometric and physical configuration of the topic and on a computational method. Removing the Doppler shift contributions of proper and rotational motions, due to the set-up of the receiver, and excluding the recombination factor of neutral hydrogen, which is irrelevant for distances within 1 AU, the calculation of the redshift can be traced back to the interactions between the radio signal and the electrons of the solar corona alone. The latter are contained in a Stroemgren sphere and photo-ionized by solar radiation in the UV and X-ray range. Furthermore, in order to have an interactional redshift contribution, the electrons have to satisfy the Wigner-Crystal Precondition for which their unitary potential energy is greater than their kinetic energy. Otherwise, a Thomson scattering process takes place in which the energy of the radio photon remains unchanged. The comparison between the gravitational redshift together with the interactional redshift detected from this study methodology and the total redshift obtained from other scientific studies shows a similarity between the curves, including the observational data, both in terms of values, trend of the graphs and single punctual variations.

关键词： Redshift Anomaly Radio Signal Pioneer-6 solar corona Plasma New Tired Light

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Kinetic Instability of Anisotropic Drift Wave Accompanied by Field Aligned Currents in solar coronal Loop

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Communications in Theoretical Physics 2018年第10期70卷 470-476页

作者： Hafsa Naim Ch.Uzma G.Murtaza Salam Chair Department of Physics GC University

solar coronal loops are frequently accompanied by the field-aligned currents, which drive instabilities if the drift velocity u0 > v A the Alfv′en velocity. For our choice of parameters, the critical threshold value of u0/v A is ～ 3.0 for growth and the corresponding current filling factor ～ 10-3-10-4. Below this value we are no longer in the kinetic *** coronal loops also have short-scale density gradients within each loop. The electron resonance in the presence of density gradient causes the drift mode to grow. We study the effect of these two free energy sources, the electron drift and the density gradient, in the presence of temperature anisotropy T⊥_α > T∥_α. These effects simultaneously exist in the coronae. Using gyrokinetic theory, we investigate the influence of these effects, examine how they interplay with each other and study the consequent growth of the magnetosonic wave. We observe that kinetic instability driven by density gradient can be suppressed by field-aligned currents. The temperature anisotropy with chosen signatures causes further stabilizing effect. The results may prove useful to study the heating mechanism of solar coronal loops, acceleration of particles and confinement of particles in the thermonuclear reactors.

关键词： solar corona coronal loops temperature anisotropy density inhomogeneity field-aligned currents gyrokinetic

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Field topologies in ideal and near-ideal magnetohydrodynamics and vortex dynamics

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 12-31页

作者： LOW B.C. High Altitude Observatory National Center for Atmospheric Research

Magnetic field topology frozen in ideal magnetohydrodynamics （MHD） and its breakage in near-ideal MHD are reviewed in two parts, clarifying and expanding basic concepts. The first part gives a physically complete description of the frozen field topology derived from magnetic flux conservation as the fundamental property, treating four conceptually related topics： Eulerian and La- grangian descriptions of three dimensional （3D） MHD, Chandrasekhar-Kendall and Euler-potential field representations, magnetic helicity, and inviscid vortex dynamics as a fluid system in physical contrast to ideal MHD. A corollary of these developments clar- ifies the challenge of achieving a high degree of the frozen-in condition in numerical MHD. The second part treats field-topology breakage centered around the Parker Magnetostatic Theorem on a general incompatibility of a continuous magnetic field with the dual demand of force-free equilibrium and an arbitrarily prescribed, 3D field topology. Preserving field topology as a global con- straint readily results in formation of tangential magnetic discontinuities, or, equivalently, electric current-sheets of zero thickness. A similar incompatibility is present in the steady force-thermal balance of a heated radiating fluid subject to an anisotropic thermal flux conducted strictly along its frozen-in magnetic field in the low-fl limit. In a weakly resistive fluid the thinning of current sheets by these general incompatibilities inevitably results field notwithstanding the small resistivity. Strong Faraday in sheet dissipation, resistive heating and topological changes in the induction drives but also macroscopically limits this mode of energy dissipation, trapping or storing free energy in self-organized ideal-MHD structures. This property of MHD turbulence captured by the Taylor hypothesis is reviewed in relation to the Sun＇s corona, calling for a basic quantitative description of the breakdown of flux conservation in the low-resistivity li

关键词： magnetic topology magnetic reconnection current sheets magnetic helicity thermal conduction solar corona magnetohy-drodynamics interstellar clouds

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Plasma draining and replenishing near a solar active region inferred from cross-correlation between radiation intensity and Doppler shift

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Science China Earth Sciences 2015年第5期58卷 830-838页

作者： ZHANG JingBo HE JianSen YAN LiMei TU ChuanYi WANG LingHua WANG Xin Institute of Space Physics and Applied Technology Peking University

Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate solar wind. The correlation between the temporal profiles of the radiation intensity and Doppler shift for each emission line are analyzed. And three small regions with positive correlations for all the five emission lines are selected for a detailed analysis. In this work, Doppler blue （red） shift is defined as negative （positive）. We find that in Region 1, the radiation intensity （Doppler velocity） decreases by about 15% （about 3 km s-X）, and logarithmical differential emission measures （lg（DEMs）） reduces by about 0.06-0.10% at all temperatures, called ＂weak dimming＂, during a 30-min interval. In Region 2 and Region 3, however, the radiation intensity （Doppler velocity） increases by about 15% （about 3 km s-l）, and lg（DEMs） increases by about 0.06%~0.10% at all tempera- tures, called ＂weak brightening＂. Such weak dimming （weak brightening） could reflect a slow draining （replenishing） of plas- ma in the solar wind flux tubes, possibly due to a larger （smaller） outflow flux at high altitude than at low altitude. These sug- gest that the plasma supply could be intermittent with an alternation of draining and replenishing, for which the underlying physical process is yet unknown, at the source region of slow/intermediate solar wind.

关键词： solar corona solar wind active region

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Validation of Novel Model for Identification of Thermal Conditions in the Low corona

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Advances in Aerospace Science and Technology 2022年第1期7卷 52-84页

作者： Daniel B. Berdichevsky Jenny M. Rodríguez Gómez Luis E. Vieira Alisson Dal Lago College Park Maryland USA IFIR/UNR-CONICET Rosario Argentina The Catholic University of America Washington D.C. USA NASA Goddard Space Flight Center Greenbelt Maryland USA Instituto Nacional de Pesquisas Espaciais INPE S&atilde o José dos Campos Brazil

The electron density and temperature key properties of the neutral-magnetized plasma in the solar corona, which are predicted with a novel model, provide an interesting window along the whole solar cycle. In this work, we test the quantitative validity of the model and prove that the coronal Density and Temperature (CODET) is reliable. Furthermore, this work contrasts the CODET model results with alternative observational remote and in-situ datasets during the simplest conditions of the quiescent corona near the solar minimum. This successful outcome/validation of the CODET model allowed a good qualitative density and temperature retrieval in the solar corona covering a large portion of time interval from solar cycles 23 and 24.

关键词： solar corona Electron Density Temperature

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Hypersphere World-Universe Model: Basic Ideas

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Journal of High Energy Physics, Gravitation and Cosmology 2020年第4期6卷 710-752页

作者： Vladimir S. Netchitailo Biolase Inc. 4 Cromwell Irvine CA USA

Hypersphere World-Universe Model (WUM) envisions Matter carried from the Universe into the World from the fourth spatial dimension by Dark Matter Particles (DMPs). Luminous Matter is a byproduct of Dark Matter (DM) self-annihilation. WUM introduces Dark Epoch (spanning from the Beginning of the World for 0.45 billion years) and Luminous Epoch (ever since for 13.77 billion years). Big Bang discussed in Standard Cosmology (SC) is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning DM Supercluster’s Cores and self-annihilation of DMPs. WUM solves a number of physical problems in SC and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;coronal Heating problem in solar physics—temperature of Sun’s corona exceeding that of photosphere by millions of degrees;Cores of Sun and Earth rotating faster than their surfaces;Diversity of Gravitationally-Rounded objects in solar system and their Internal Heating. Model makes predictions pertaining to Rest Energies of DMPs, proposes New Type of their Interactions. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements.

关键词： Hypersphere World-Universe Model Law of Conservation of Angular Momentum Dark Epoch Rotational Fission Luminous Epoch Dark Matter Particles Self-Annihilation Macroobject Shell Model Dark Matter Core Medium of the World Dark Matter Fermi Bubbles solar corona Geocorona Planetary corona Galactic Wind solar Wind Gamma-Ray Bursts Gravitational Bursts Fast Radio Bursts Dark Matter Reactor Lightning Initiation Problem Terrestrial Gamma-Ray Flashes Missing Baryon Problem Energy-Varying Photons

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