arXiv - PHYS - Space Physics最新文献_第5页

In situ observations of large amplitude Alfvén waves heating and accelerating the solar wind 对加热和加速太阳风的大振幅阿尔芬波的现场观测

arXiv - PHYS - Space Physics Pub Date : 2024-08-30 DOI: arxiv-2409.00267

Yeimy J. Rivera, Samuel T. Badman, Michael L. Stevens, Jaye L. Verniero, Julia E. Stawarz, Chen Shi, Jim M. Raines, Kristoff W. Paulson, Christopher J. Owen, Tatiana Niembro, Philippe Louarn, Stefano A. Livi, Susan T. Lepri, Justin C. Kasper, Timothy S. Horbury, Jasper S. Halekas, Ryan M. Dewey, Rossana De Marco, Stuart D. Bale

引用次数: 0

Relativistic and Ultra-Relativistic Electron Bursts in Earth's Magnetotail Observed by Low-Altitude Satellites 低空卫星观测到的地球磁尾中的相对论和超相对论电子爆发

arXiv - PHYS - Space Physics Pub Date : 2024-08-30 DOI: arxiv-2408.17299

Xiao-Jia Zhang, Anton V. Artemyev, Xinlin Li, Harry Arnold, Vassilis Angelopoulos, Drew L. Turner, Mykhaylo Shumko, Andrei Runov, Yang Mei, Zheng Xiang

引用次数: 0

Earth's Alfvén Wings: Unveiling Dynamic Variations of Field-line Topologies with Electron Distributions 地球的阿尔芬之翼：揭示场线拓扑与电子分布的动态变化

arXiv - PHYS - Space Physics Pub Date : 2024-08-30 DOI: arxiv-2409.00247

Harsha Gurram, Jason R. Shuster, Li-Jen Chen, Hiroshi Hasegawa, Richard E. Denton, Brandon L. Burkholder, Jason Beedle, Daniel J. Gershman, James Burch

{"title":"Earth's Alfvén Wings: Unveiling Dynamic Variations of Field-line Topologies with Electron Distributions","authors":"Harsha Gurram, Jason R. Shuster, Li-Jen Chen, Hiroshi Hasegawa, Richard E. Denton, Brandon L. Burkholder, Jason Beedle, Daniel J. Gershman, James Burch","doi":"arxiv-2409.00247","DOIUrl":"https://doi.org/arxiv-2409.00247","url":null,"abstract":"The magnetic cloud (MC) of the Coronal Mass Ejection on April 24, 2023,\u0000contains sub-Alfv'{e}nic solar wind, transforming Earth's magnetosphere from\u0000conventional bow-shock magnetotail configuration to Alfv'{e}n wings. Utilizing\u0000measurements from the Magnetosphere Multiscale (MMS) mission, we present for\u0000the first time electron distribution signatures as the spacecraft traverses\u0000through various magnetic topologies during this transformation. Specifically,\u0000we characterize electrons inside the sub-Alfv'{e}nic MC, on the dawn-dusk wing\u0000field lines and on the closed field lines. The signatures include strahl\u0000electrons in MC regions and energetic keV electrons streaming along the dawn\u0000and dusk wing field lines. We demonstrate the distribution signatures of dual\u0000wing reconnection, defined as reconnection between dawn-dusk Alfv'{e}n wing\u0000field lines and the IMF. These signatures include four electron populations\u0000comprised of partially-depleted MC electrons and bi-directional energetic\u0000electrons with variations in energy and pitch-angle. The distributions reveal\u0000evidence of bursty magnetic reconnection under northward IMF.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"129 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142178411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Near-Real Time Thermospheric Density Retrieval from Precise Low Earth Orbit Spacecraft Ephemerides During Geomagnetic Storms 地磁暴期间从精确的低地球轨道航天器星历表获取近实时热层密度

arXiv - PHYS - Space Physics Pub Date : 2024-08-29 DOI: arxiv-2408.16805

Charles Constant, Santosh Bhattarai, Indigo Brownhall, Anasuya Aruliah, Marek Ziebart

{"title":"Near-Real Time Thermospheric Density Retrieval from Precise Low Earth Orbit Spacecraft Ephemerides During Geomagnetic Storms","authors":"Charles Constant, Santosh Bhattarai, Indigo Brownhall, Anasuya Aruliah, Marek Ziebart","doi":"arxiv-2408.16805","DOIUrl":"https://doi.org/arxiv-2408.16805","url":null,"abstract":"We present a methodology to generate low-latency, high spatio-temporal\u0000resolution thermospheric density estimates using publicly available Low Earth\u0000Orbit (LEO) spacecraft ephemerides. This provides a means of generating density\u0000estimates that can be used in a data-assimilative context by the satellite\u0000operations and thermosphere communities. It also contributes to the data base\u0000of high-resolution density estimates during geomagnetic storms -- which remains\u0000one of the major gaps for the development and benchmarking of density models.\u0000Using accelerometer-derived densities from the Gravity Recovery And Climate\u0000Experiment Follow-On (GRACE-FO) spacecraft as truth, our method surpasses\u0000Energy Dissipation Rate-Type density retrieval techniques and three widely used\u0000operational density models in terms of accuracy: EDR (103.37%), JB2008\u0000(85.43%), DTM2000 (52.73%), and NRLMSISE-00 (12.31%). We demonstrate the\u0000robustness of our methodology during a critical time for spacecraft operators\u0000-- attempting to operate in the presence of geomagnetic storms, by\u0000reconstructing density profiles along the orbits of three LEO satellites during\u000080 geomagnetic storms. These profiles exhibit high spatial and temporal\u0000resolution compared to three operational thermospheric models, highlighting the\u0000operational applicability and potential for their use in model validation. Our\u0000findings suggest that the increasing availability of precise orbit\u0000determination data offers a valuable, yet underutilized, resource that could\u0000provide a significant improvement to data assimilative thermospheric models,\u0000ultimately enhancing both spacecraft operations and thermospheric modeling\u0000efforts.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142178427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Catastrophic cooling in optically thin plasmas 光学稀薄等离子体中的灾难性冷却

arXiv - PHYS - Space Physics Pub Date : 2024-08-28 DOI: arxiv-2408.15869

Tim Waters, Amanda Stricklan

{"title":"Catastrophic cooling in optically thin plasmas","authors":"Tim Waters, Amanda Stricklan","doi":"arxiv-2408.15869","DOIUrl":"https://doi.org/arxiv-2408.15869","url":null,"abstract":"The solar corona is the prototypical example of a low density environment\u0000heated to high temperatures by external sources. The plasma cools radiatively,\u0000and because it is optically thin to this radiation, it becomes possible to\u0000model the density, velocity, and temperature structure of the system by\u0000modifying the MHD equations to include energy source terms that approximate the\u0000local heating and cooling rates. The solutions can be highly inhomogeneous and\u0000even multiphase because the well known linear instability associated with these\u0000source terms, thermal instability, leads to a catastrophic heating and cooling\u0000of the plasma in the nonlinear regime. Here we show that there is a separate,\u0000much simpler instance of catastrophic heating and cooling accompanying these\u0000source terms that can rival thermal instability in dynamical importance. The\u0000linear stability criterion is the isochoric one identified by Parker (1953),\u0000and we demonstrate that cooling functions derived from collisional ionization\u0000equilibrium are highly prone to violating this criterion. If catastrophic\u0000cooling instability can act locally in global simulations, then it is an\u0000alternative mechanism for forming condensations, and due to its nonequilibrium\u0000character, it may be relevant to explaining a host of phenomena associated with\u0000the production of cooler gas in hot, low density plasmas.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142178429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Orbital Dynamics of the Solar Basin 太阳盆地的轨道动力学

arXiv - PHYS - Space Physics Pub Date : 2024-08-28 DOI: arxiv-2408.16041

Cara Giovanetti, Robert Lasenby, Ken Van Tilburg

{"title":"Orbital Dynamics of the Solar Basin","authors":"Cara Giovanetti, Robert Lasenby, Ken Van Tilburg","doi":"arxiv-2408.16041","DOIUrl":"https://doi.org/arxiv-2408.16041","url":null,"abstract":"We study the dynamics of the solar basin -- the accumulated population of\u0000weakly-interacting particles on bound orbits in the Solar System. We focus on\u0000particles starting off on Sun-crossing orbits, corresponding to initial\u0000conditions of production inside the Sun, and investigate their evolution over\u0000the age of the Solar System. A combination of analytic methods, secular\u0000perturbation theory, and direct numerical integration of orbits sheds light on\u0000the long- and short-term evolution of a population of test particles orbiting\u0000the Sun and perturbed by the planets. Our main results are that the effective\u0000lifetime of a solar basin at Earth's location is $tau_{rm eff} = 1.20pm 0.09\u0000,mathrm{Gyr}$, and that there is annual (semi-annual) modulation of the basin\u0000density with known phase and amplitude at the fractional level of 6.5% (2.2%).\u0000These results have important implications for direct detection searches of\u0000solar basin particles, and the strong temporal modulation signature yields a\u0000robust discovery channel. Our simulations can also be interpreted in the\u0000context of gravitational capture of dark matter in the Solar System, with\u0000consequences for any dark-matter phenomenon that may occur below the local\u0000escape velocity.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142178428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantifying & Mitigating Satellite Constellation Interference with SatHub 利用 SatHub 量化和减轻卫星星座干扰

arXiv - PHYS - Space Physics Pub Date : 2024-08-27 DOI: arxiv-2408.15223

Meredith L. Rawls, Constance E. Walker, Michelle Dadighat, Harrison Krantz, Siegfried Eggl, Mike Peel

引用次数: 0

Interplanetary Causes and Impacts of the 2024 May Superstorm on the Geosphere: An Overview 2024 年 5 月超级风暴的星际成因及其对地圈的影响：概述

arXiv - PHYS - Space Physics Pub Date : 2024-08-27 DOI: arxiv-2408.14799

Rajkumar Hajra, Bruce Tsatnam Tsurutani, Gurbax Singh Lakhina, Quanming Lu, Aimin Du

{"title":"Interplanetary Causes and Impacts of the 2024 May Superstorm on the Geosphere: An Overview","authors":"Rajkumar Hajra, Bruce Tsatnam Tsurutani, Gurbax Singh Lakhina, Quanming Lu, Aimin Du","doi":"arxiv-2408.14799","DOIUrl":"https://doi.org/arxiv-2408.14799","url":null,"abstract":"The recent superstorm of 2024 May 10-11 is the second largest geomagnetic\u0000storm in the space age and the only one that has simultaneous interplanetary\u0000data (there were no interplanetary data for the 1989 March storm). The May\u0000superstorm was characterized by a sudden impulse (SI+) amplitude of +88 nT,\u0000followed by a three-step storm main phase development which had a total\u0000duration of ~9 hr. The cause of the first storm main phase with a peak SYM-H\u0000intensity of -183 nT was a fast forward interplanetary shock (magnetosonic Mach\u0000number Mms ~7.2) and an interplanetary sheath with southward interplanetary\u0000magnetic field component Bs of ~40 nT. The cause of the second storm main phase\u0000with a SYM-H intensity of -354 nT was a deepening of the sheath Bs to ~43 nT. A\u0000magnetosonic wave (Mms ~0.6) compressed the sheath to a high magnetic field\u0000strength of ~71 nT. Intensified Bs of ~48 nT was the cause of the third and\u0000most intense storm main phase with a SYM-H intensity of -518 nT. Three magnetic\u0000cloud events with Bs fields of ~25-40 nT occurred in the storm recovery phase,\u0000lengthening the recovery to ~2.8 days. At geosynchronous orbit, ~76 keV to ~1.5\u0000MeV electrons exhibited ~1-3 orders of magnitude flux decreases following the\u0000shock/sheath impingement onto the magnetosphere. The cosmic ray decreases at\u0000Dome C, Antarctica (effective vertical cutoff rigidity <0.01 GV) and Oulu,\u0000Finland (rigidity ~0.8 GV) were ~17% and ~11%, respectively relative to quite\u0000time values. Strong ionospheric current flows resulted in extreme\u0000geomagnetically induced currents of ~30-40 A in the sub-auroral region. The\u0000storm period is characterized by strong polar region field-aligned currents,\u0000with ~10 times intensification during the main phase, and equatorward expansion\u0000down to ~50 deg geomagnetic (altitude-adjusted) latitude.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probing coronal mass ejections inclination effects with EUHFORIA 利用EUHFORIA探测日冕物质抛射的倾角效应

arXiv - PHYS - Space Physics Pub Date : 2024-08-27 DOI: arxiv-2408.14971

Karmen Martinić, Eleanna Asvestari, Mateja Dumbović, Tobias Rindlisbacher, Manuela Temmer, Bojan Vršnak

{"title":"Probing coronal mass ejections inclination effects with EUHFORIA","authors":"Karmen Martinić, Eleanna Asvestari, Mateja Dumbović, Tobias Rindlisbacher, Manuela Temmer, Bojan Vršnak","doi":"arxiv-2408.14971","DOIUrl":"https://doi.org/arxiv-2408.14971","url":null,"abstract":"Coronal mass ejections (CMEs) are complex magnetized plasma structures in\u0000which the magnetic field spirals around a central axis, forming what is known\u0000as a flux rope (FR). The central FR axis can be oriented at any angle to the\u0000ecliptic. Throughout its journey, a CME will encounter interplanetary magnetic\u0000field and solar wind which are neither homogeneous nor isotropic. Consequently,\u0000CMEs with different orientations will encounter different ambient medium\u0000conditions and, thus, the interaction of a CME with its surrounding environment\u0000will vary depending on the orientation of its FR axis, among other factors.\u0000This study aims to understand the effect of inclination on CME propagation. We\u0000performed simulations with the EUHFORIA 3D magnetohydrodynamic model. This\u0000study focuses on two CMEs modelled as spheromaks with nearly identical\u0000properties, differing only by their inclination. We show the effects of CME\u0000orientation on sheath evolution, MHD drag, and non-radial flows by analyzing\u0000the model data from a swarm of 81 virtual spacecraft scattered across the inner\u0000heliospheric. We have found that the sheath duration increases with radial\u0000distance from the Sun and that the rate of increase is greater on the flanks of\u0000the CME. Non-radial flows within the studied sheath region appear larger\u0000outside the ecliptic plane, indicating a \"sliding\" of the IMF in the out-of\u0000ecliptic plane. We found that the calculated drag parameter does not remain\u0000constant with radial distance and that the inclination dependence of the drag\u0000parameter can not be resolved with our numerical setup.","PeriodicalId":501423,"journal":{"name":"arXiv - PHYS - Space Physics","volume":"390 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142178433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Long-term variation of the solar polar magnetic fields at different latitudes 不同纬度太阳极地磁场的长期变化

arXiv - PHYS - Space Physics Pub Date : 2024-08-27 DOI: arxiv-2408.15168

Shuhong Yang, Jie Jiang, Zifan Wang, Yijun Hou, Chunlan Jin, Qiao Song, Yukun Luo, Ting Li, Jun Zhang, Yuzong Zhang, Guiping Zhou, Yuanyong Deng, Jingxiu Wang

引用次数: 0