Bibliography





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Found 58 entries in the Bibliography.


Showing entries from 1 through 50


2022

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribution of externally provided energy to the composing species? (B) How and by how much do plasma-neutral gas interactions contribute toward the growth of heavy complex molecules and biomolecules? Answering these questions is an absolute prerequisite for addressing the long-standing questions of atmospheric escape, the origin of biomolecules, and their role in the evolution of planets, moons, or comets, under the influence of energy sources in the form of electromagnetic and corpuscular radiation, because low-energy ion-neutral cross-sections in space cannot be reproduced quantitatively in laboratories for conditions of satisfying, particularly, (1) low-temperatures, (2) tenuous or strong gradients or layered media, and (3) in low-gravity plasma. Measurements with a minimum core instrument package (\textless 15 kg) can be used to perform such investigations in many different conditions and should be included in all deep-space missions. These investigations, if specific ranges of background parameters are considered, can also be pursued for Earth, Mars, and Venus.

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Local Persistent Ionospheric Positive Responses to the Geomagnetic Storm in August 2018 Using BDS-GEO Satellites over Low-Latitude Regions in Eastern Hemisphere

We present the ionospheric disturbance responses over low-latitude regions by using total electron content from Geostationary Earth Orbit (GEO) satellites of the BeiDou Navigation Satellite System (BDS), ionosonde data and Swarm satellite data, during the geomagnetic storm in August 2018. The results show that a prominent total electron content (TEC) enhancement over low-latitude regions is observed during the main phase of the storm. There is a persistent TEC increase lasting for about 1–2 days and a moderately positive disturbance response during the recovery phase on 27–28 August, which distinguishes from the general performance of ionospheric TEC in the previous storms. We also find that this phenomenon is a unique local-area disturbance of the ionosphere during the recovery phase of the storm. The enhanced foF2 and hmF2 of the ionospheric F2 layer is observed by SANYA and LEARMONTH ionosonde stations during the recovery phase. The electron density from Swarm satellites shows a strong equatorial ionization anomaly (EIA) crest over the low-latitude area during the main phase of storm, which is simultaneous with the uplift of the ionospheric F2 layer from the SANYA ionosonde. Meanwhile, the thermosphere O/N2 ratio shows a local increase on 27–28 August over low-latitude regions. From the above results, this study suggests that the uplift of F layer height and the enhanced O/N2 ratio are possibly main factors causing the local-area positive disturbance responses during the recovery phase of the storm in August 2018.

Tang, Jun; Gao, Xin; Yang, Dengpan; Zhong, Zhengyu; Huo, Xingliang; Wu, Xuequn;

Published by: Remote Sensing      Published on: jan

YEAR: 2022     DOI: 10.3390/rs14092272

BDS-GEO; differential code biases; geomagnetic storm; Ionospheric disturbance; TEC

Multiresolution Data Assimilation for Auroral Energy Flux and Mean Energy Using DMSP SSUSI, THEMIS ASI, and An Empirical Model

We apply a multiresolution Gaussian process model (Lattice Kriging) to combine satellite observations, ground‐based observations, and an empirical auroral model, to produce the

Wu, Haonan; Tan, Xiyan; Zhang, Qiong; Huang, Whitney; Lu, Xian; Nishimura, Yukitoshi; Zhang, Yongliang;

Published by: Space Weather      Published on:

YEAR: 2022     DOI: 10.1029/2022SW003146

Geomagnetic and Solar Dependencies of Midlatitude E-Region Irregularity Occurrence Rate: A Climatology Based on Wuhan VHF Radar Observations

By using Wuhan VHF radar, we show the morphological features of E-region field-aligned irregularity (FAI) occurrence at Wuhan during 2015–2020. Statistical results present that E-region FAI occurrence reaches a maximum after sunset in summer season. According to Doppler spectrum features, type-2 irregularity is predominantly observed at Wuhan. In addition, we observed a remarkable correlation between E-region FAI occurrence and geomagnetic activity, which includes periods of positive correlation and negative correlation depending on different geomagnetic conditions. The strong negative correlation also exists between E-region FAI occurrence and solar activity. In our observed results, we find that E-region FAI occurrence shows a strong linkage with local sporadic E (ES) layer. A quantitative analysis of linear theory of plasma instability in the E-region at midlatitudes is also presented in our study. The calculated results of linear growth rate indicate the importance of plasma density gradient of local ES layer and field-line-integrated Pedersen conductivity on the generation of E-region FAI. The geomagnetic and solar variations of E-region FAI occurrence are also discussed in this study, which show a dependence on the geomagnetic and solar variations of both meteor rate and medium-scale traveling ionospheric disturbance occurrence.

Liu, Yi; Zhou, Chen; Xu, Tong; Deng, Zhongxin; Du, Zhitao; Lan, Ting; Tang, Qiong; Zhu, Yunzhou; Wang, Zhuangkai; Zhao, Zhengyu;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2022     DOI: 10.1029/2021JA029597

2021

A ROTI-Aided Equatorial Plasma Bubbles Detection Method

In this study, we present a Rate of Total Electron Content Index (ROTI)-aided equatorial plasma bubbles (EPBs) detection method based on a Global Navigation Satellite System (GNSS) ionospheric Total Electron Content (TEC). This technique seeks the EPBs occurrence time according to the ROTI values and then extracts the detrended ionospheric TEC series, which include EPBs signals using a low-order, partial polynomial fitting strategy. The EPBs over the Hong Kong area during the year of 2014 were detected using this technique. The results show that the temporal distribution and occurrence of EPBs over the Hong Kong area are consistent with that of previous reports, and most of the TEC depletion error is smaller than 1.5 TECU (average is 0.63 TECU), suggesting that the detection method is feasible and highly accurate. Furthermore, this technique can extract the TEC depletion series more effectively, especially for those with a long duration, compared to previous method.

Tang, Long; Louis, Osei-Poku; Chen, Wu; Chen, Mingli;

Published by: Remote Sensing      Published on: jan

YEAR: 2021     DOI: 10.3390/rs13214356

Ionosphere; detection method; equatorial plasma bubbles; GNSS; ROTI

Ionospheric response to the 17 March and 22 June 2015 geomagnetic storms over Wuhan region using GNSS-based tomographic technique

By using the data of GNSS (Global Navigation Satellite System) observation from Crustal Movement Observation Network of China (CMONOC), ionospheric electron density (IED) distributions reconstructed by using computerized ionospheric tomography (CIT) technique are used to investigate the ionospheric storm effects over Wuhan region during 17 March and 22 June 2015 geomagnetic storm periods. F-region critical frequency (foF2) at Wuhan ionosonde station shows an obvious decrease during recovery phase of the St. Patrick’s Day geomagnetic storm. Moreover, tomographic results present that the decrease in electron density begins at 12:00 UT on 17 March during the storm main phase. Also, foF2 shows a long-lasting negative storm effect during the recovery phase of the 22 June 2015 geomagnetic storm. Electron density chromatography presents the evident decrease during the storm day in accordance with the ionosonde observation. These ionospheric negative storm effects are probably associated with changes of chemical composition, PPEF and DDEF from high latitudes.

Feng, Jian; Zhou, Yufeng; Zhou, Yan; Gao, Shuaihe; Zhou, Chen; Tang, Qiong; Liu, Yi;

Published by: Advances in Space Research      Published on: jan

YEAR: 2021     DOI: 10.1016/j.asr.2020.10.008

Ionospheric electron density distributions; ionospheric storm effects; Multiplication algebraic reconstruction technique

2020

The physics of space weather/solar-terrestrial physics (STP): what we know now and what the current and future challenges are

Major geomagnetic storms are caused by un-usually intense solar wind southward magnetic fields thatimpinge upon the Earth\textquoterights magnetosphere (Dungey, 1961).How can we predict the occurrence of future interplanetary events? Do we currently know enough of the underlying physics and do we have sufficient observations of solar wind phenomena that will impinge upon the Earth\textquoterights magnetosphere? We view this as the most important challenge in space weather. We discuss the case for magnetic clouds (MCs), interplanetary sheaths upstream of interplanetary coronal mass ejections (ICMEs), corotating interactionregions (CIRs) and solar wind high-speed streams (HSSs).The sheath- and CIR-related magnetic storms will be difficult to predict and will require better knowledge of the slow solar wind and modeling to solve. For interplanetaryspace weather, there are challenges for understanding the fluences and spectra of solar energetic particles (SEPs). This will require better knowledge of interplanetary shock properties as they propagate and evolve going from the Sun to1 AU (and beyond), the upstream slow solar wind and energetic \textquotedblleftseed\textquotedblright particles. Dayside aurora, triggering of night-side substorms, and formation of new radiation belts can all be caused by shock and interplanetary ram pressure impingements onto the Earth\textquoterights magnetosphere. The acceleration and loss of relativistic magnetospheric \textquotedblleftkiller\textquotedblright electronsand prompt penetrating electric fields in terms of causingpositive and negative ionospheric storms are reasonably well understood, but refinements are still needed. The forecasting of extreme events (extreme shocks, extreme solar energeticparticle events, and extreme geomagnetic storms (Carrington events or greater)) are also discussed. Energetic particle precipitation into the atmosphere and ozone destructionare briefly discussed. For many of the studies, the Parker Solar Probe, Solar Orbiter, Magnetospheric Multiscale Mission(MMS), Arase, and SWARM data will be useful.

Tsurutani, Bruce; Lakhina, Gurbax; Hajra, Rajkumar;

Published by: Nonlinear Processes in Geophysics      Published on: 01/2020

YEAR: 2020     DOI: 10.5194/npg-27-75-2020

Magnetospheric Conditions for STEVE and SAID: Particle Injection, Substorm Surge, and Field-Aligned Currents

Nishimura, Y; Yang, J; Weygand, JM; Wang, W; Kosar, B; Donovan, EF; , Angelopoulos; Paxton, LJ; Nishitani, N;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2020     DOI:

Unprecedented hemispheric asymmetries during a surprise ionospheric storm: A game of drivers

Astafyeva, Elvira; Bagiya, Mala; Förster, Matthias; Nishitani, Nozomu;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2020     DOI:

Magnetospheric conditions for STEVE and SAID: Particle injection, substorm surge, and field-aligned currents

Nishimura, Y; Yang, J; Weygand, JM; Wang, W; Kosar, B; Donovan, EF; , Angelopoulos; Paxton, LJ; Nishitani, N;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2020     DOI:

2019

Review of the accomplishments of mid-latitude Super Dual Auroral Radar Network (SuperDARN) HF radars

The Super Dual Auroral Radar Network (SuperDARN) is a network of high-frequency (HF) radars located in the high- and mid-latitude regions of both hemispheres that is operated under international cooperation. The network was originally designed for monitoring the dynamics of the ionosphere and upper atmosphere in the high-latitude regions. However, over the last approximately 15 years, SuperDARN has expanded into the mid-latitude regions. With radar coverage that now extends continuously from auroral to sub-auroral and mid-latitudes, a wide variety of new scientific findings have been obtained. In this paper, the background of mid-latitude SuperDARN is presented at first. Then, the accomplishments made with mid-latitude SuperDARN radars are reviewed in five specified scientific and technical areas: convection, ionospheric irregularities, HF propagation analysis, ion-neutral interactions, and magnetohydrodynamic (MHD) waves. Finally, the present status of mid-latitude SuperDARN is updated and directions for future research are discussed.

Nishitani, Nozomu; Ruohoniemi, John; Lester, Mark; Baker, Joseph; Koustov, Alexandre; Shepherd, Simon; Chisham, Gareth; Hori, Tomoaki; Thomas, Evan; Makarevich, Roman; , others;

Published by: Progress in Earth and Planetary Science      Published on:

YEAR: 2019     DOI: 10.1186/s40645-019-0270-5

Space weather forecasting: What we know now and what are the current and future challenges

Geomagnetic storms are caused by solar wind southward magnetic fields that impinge upon the Earth’s magnetosphere (Dungey, 1961). How can we forecast the occurrence of these interplanetary events? We view this as the most important challenge in Space Weather. We discuss the case for magnetic clouds (MCs), interplanetary sheaths upstream of ICMEs, corotating interaction regions (CIRs) and high speed streams (HSSs). The sheath- and CIR-related magnetic storms will be difficult to predict and will require better knowledge of the slow solar wind and modeling to solve.

Tsurutani, Bruce; Lakhina, Gurbax; Hajra, Rajkumar;

Published by: Nonlinear Processes Geophys. Discuss      Published on:

YEAR: 2019     DOI:

2018

IPIM Modeling of the Ionospheric F 2 Layer Depletion at High Latitudes During a High-Speed Stream Event

Our aim is to understand the effect of high-speed stream events on the high-latitude ionosphere and more specifically the decrease of the foF2 frequency during the entire day following the impact. First, we have selected one summertime event, for which a large data set was available: Super Dual Auroral Radar Network (SuperDARN) and European Incoherent SCATter (EISCAT) radars, Troms\o and Sodankylä ionosondes, and the CHAllenging Minisatellite Payload (CHAMP) satellite. We modeled with the IPIM model (IRAP Plasmasphere Ionosphere Model) the dynamics of the ionosphere at Troms\o and Sodankylä using inputs derived from the data. The simulations nicely match the measurements made by the EISCAT radar and the ionosondes, and we showed that the decrease of foF2 is associated with a transition from F2 to F1 layer resulting from a decrease of neutral atomic oxygen concentration. Modeling showed that electrodynamics can explain short-term behavior on the scale of a few hours, but long-term behavior on the scale of a few days results from the perturbation induced in the atmosphere. Enhancement of convection is responsible for a sharp increase of the ion temperature by Joule heating, leading through chemistry to an immediate reduction of the F2 layer. Then, ion drag on neutrals is responsible for a rapid heating and expansion of the thermosphere. This expansion affects atomic oxygen through nonthermal upward flow, which results in a decrease of its concentration and amplifies the decrease of [O]/[N2] ratio. This thermospheric change explains long-term extinction of the F2 layer.

Marchaudon, A.; Blelly, P.-L.; Grandin, M.; Aikio, A.; Kozlovsky, A.; Virtanen, I.;

Published by: Journal of Geophysical Research: Space Physics      Published on: 08/2018

YEAR: 2018     DOI: 10.1029/2018JA025744

IPIM Modeling of the Ionospheric F 2 Layer Depletion at High Latitudes During a High-Speed Stream Event

Our aim is to understand the effect of high‐speed stream events on the high‐latitude ionosphere and more specifically the decrease of the f o F 2 frequency during the entire day

Marchaudon, A; Blelly, P-L; Grandin, M; Aikio, A; Kozlovsky, A; Virtanen, I;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2018     DOI: 10.1029/2018JA025744

2017

Driving of Dramatic Geomagnetic Activity by Enhancement of Meso-Scale Polar-cap Flows

Lyons, Larry; Gallardo-Lacourt, Bea; Zou, Ying; Nishimura, Yukitoshi; Anderson, Phillip; Angelopoulos, VASSILIS; Ruohoniemi, Michael; Mitchell, Elizabeth; Paxton, Larry; Nishitani, Nozomu;

Published by:       Published on:

YEAR: 2017     DOI:

2016

Peculiar features of the low-latitude and midlatitude ionospheric response to the St. Patrick's Day geomagnetic storm of 17 March 2015

The current study aims at investigating and identifying the ionospheric effects of the geomagnetic storm that occurred during 17\textendash19 March 2015. Incidentally, with SYM-H hitting a minimum of -232\ nT, this was the strongest storm of the current solar cycle 24. The study investigates how the storm has affected the equatorial, low-latitude, and midlatitude ionosphere in the American and the European sectors using available ground-based ionosonde and GPS TEC (total electron content) data. The possible effects of prompt electric field penetration is observed in both sectors during the main phase of the storm. In the American sector, the coexistence of both positive and negative ionospheric storm phases are observed at low latitudes and midlatitudes to high latitudes, respectively. The positive storm phase is mainly due to the prompt penetration electric fields. The negative storm phase in the midlatitude region is a combined effect of disturbance dynamo electric fields, the equatorward shift of the midlatitude density trough, and the equatorward compression of the plasmapause in combination with chemical compositional changes. Strong negative ionospheric storm phase is observed in both ionosonde and TEC observations during the recovery phase which also shows a strong hemispherical asymmetry. Additionally, the variation of equatorial ionization anomaly as seen through the SWARM constellation plasma measurements across different longitudes has been discussed. We, also, take a look at the performance of the IRI Real-Time Assimilative Mapping during this storm as an ionospheric space weather tool.

Nayak, Chinmaya; Tsai, L.-C.; Su, S.-Y.; Galkin, I.; Tan, Adrian; Nofri, Ed; Jamjareegulgarn, Punyawi;

Published by: Journal of Geophysical Research: Space Physics      Published on: 07/2016

YEAR: 2016     DOI: 10.1002/2016JA022489

Solar wind driving of ionosphere-thermosphere responses in three storms near St. Patrick's Day in 2012, 2013, and 2015

We identify interplanetary plasma regions associated with three intense interplanetary coronal mass ejections (ICMEs)-driven geomagnetic storm intervals which occurred around the same time of the year: day of year 74\textendash79 (March) of 2012, 2013, and 2015. We show that differences in solar wind drivers lead to different dynamical ionosphere-thermosphere (IT) responses and to different preconditioning of the IT system. We introduce a new hourly based global metric for average low-latitude and northern middle-latitude vertical total electron content responses in the morning, afternoon, and evening local time ranges, derived from measurements from globally distributed Global Navigation Satellite System ground stations. Our novel technique of estimating nitric oxide (NO) cooling radiation in 11\textdegree latitudinal zones is based on Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) measurements. The thermospheric cooling throughout the storm phases is studied with this high latitudinal resolution for the first time. Additionally, TIMED/Global Ultraviolet Imager (GUVI) observations of the dynamical response of the thermospheric composition (O/N2 ratio) are utilized to study negative ionospheric storm effects. Based on these data sets, we describe and quantify distinct IT responses to driving by ICME sheaths, magnetic clouds, coronal loop remnants, plasma discontinuities, and high-speed streams following ICMEs. Our analysis of coupling functions indicates strong connection between coupling with the solar wind and IT system response in ICME-type storms and also some differences. Knowledge of interplanetary features is crucial for understanding IT storm dynamics.

Verkhoglyadova, O.; Tsurutani, B.; Mannucci, A.; Mlynczak, M.; Hunt, L.; Paxton, L.; Komjathy, A.;

Published by: Journal of Geophysical Research: Space Physics      Published on: 07/2016

YEAR: 2016     DOI: 10.1002/jgra.v121.910.1002/2016JA022883

Heliosphere-ionosphere-thermosphere coupling and energy budget in geomagnetic storms

1. Solar irradiance: F10. 7 2. High-latitude electric and magnetic field potential patterns and field-aligned currents (FAC): empirical Weimer05 model (Weimer, 2005), can use AMIE input

Verkhoglyadova, OP; Mannucci, AJ; Meng, X; Komjathy, A; Mlynczak, MG; Hunt, LA; Tsurutani, BT;

Published by:       Published on:

YEAR: 2016     DOI:

2015

Use of radio occultation to probe the high-latitude ionosphere

We have explored the use of COSMIC data to provide valuable scientific information on the ionospheric impacts of energetic particle precipitation during geomagnetic storms. Ionospheric electron density in the E region, and hence ionospheric conductivity, is significantly altered by precipitating particles from the magnetosphere. This has global impacts on the thermosphere\textendashionosphere because of the important role of conductivity on high-latitude Joule heating. Two high-speed stream (HSS) and two coronal mass ejection (CME) storms are examined with the COSMIC data. We find clear correlation between geomagnetic activity and electron density retrievals from COSMIC. At nighttime local times, the number of profiles with maximum electron densities in the E layer (below 200 km altitude) is well correlated with geomagnetic activity. We interpret this to mean that electron density increases due to precipitation are captured by the COSMIC profiles. These "E-layer-dominant ionosphere" (ELDI) profiles have geomagnetic latitudes that are consistent with climatological models of the auroral location. For the two HSS storms that occurred in May of 2011 and 2012, a strong hemispheric asymmetry is observed, with nearly all the ELDI profiles found in the Southern, less sunlit, Hemisphere. Stronger aurora and precipitation have been observed before in winter hemispheres, but the degree of asymmetry deserves further study. For the two CME storms, occurring in July and November of 2012, large increases in the number of ELDI profiles are found starting in the storm\textquoterights main phase but continuing for several days into the recovery phase. Analysis of the COSMIC profiles was extended to all local times for the July 2012 CME storm by relaxing the ELDI criterion and instead visually inspecting all profiles above 50\textdegree magnetic latitude for signatures of precipitation in the E region. For 9 days during the July 2012 period, we find a signature of precipitation occurs nearly uniformly in local time, although the magnitude of electron density increase may vary with local time. The latitudinal extent of the precipitation layers is generally consistent with auroral climatology. However, after the storm main phase on 14 July 2012 the precipitation tended to be somewhat more equatorward than the climatology (by about 5\textendash10\textdegree latitude) and equatorward of the auroral boundary data acquired from the SSUSI sensor onboard the F18 DMSP satellite. We conclude that, if analyzed appropriately, high-latitude COSMIC profiles have the potential to contribute to our understanding of MI coupling processes and extend and improve existing models of the auroral region.

Mannucci, A.; Tsurutani, B.; Verkhoglyadova, O.; Komjathy, A.; Pi, X.;

Published by: Atmospheric Measurement Techniques      Published on: 07/2015

YEAR: 2015     DOI: 10.5194/amt-8-2789-2015

Short-term variability of the Sun-Earth system: an overview of progress made during the CAWSES-II period

This paper presents an overview of results obtained during the CAWSES-II period on the short-term variability of the Sun and how it affects the near-Earth space environment. CAWSES-II was planned to examine the behavior of the solar-terrestrial system as the solar activity climbed to its maximum phase in solar cycle 24. After a deep minimum following cycle 23, the Sun climbed to a very weak maximum in terms of the sunspot number in cycle 24 (MiniMax24), so many of the results presented here refer to this weak activity in comparison with cycle 23. The short-term variability that has immediate consequence to Earth and geospace manifests as solar eruptions from closed-field regions and high-speed streams from coronal holes.

Gopalswamy, Nat; Tsurutani, Bruce; Yan, Yihua;

Published by: Progress in Earth and Planetary Science      Published on:

YEAR: 2015     DOI: 10.1186/s40645-015-0043-8

Solar wind driving of ionosphere-thermosphere responses during three storms on St. Patrick's Day.

Verkhoglyadova, Olga; Tsurutani, Bruce; Mannucci, Anthony; Komjathy, Attila; Mlynczak, Martin; Hunt, Linda; Paxton, Larry;

Published by:       Published on:

YEAR: 2015     DOI:

2014

Interplanetary magnetic field By control of prompt total electron content increases during superstorms

Large magnitude increases in ionospheric total electron content (TEC) that occur over 1\textendash3\ h on the dayside are a significant manifestation of the main phases of superstorms. For the largest superstorms of solar cycle 23 (based on the Dst index), ground networks of GPS receivers measured peak total electron content increases greater than a factor of 2 relative to quiet time TEC averaged over the broad latitude band \textpm40\textdegree for local times 1200\textendash1600\ LT. Near 30\textdegree latitude, the Halloween storms of October 29\textendash30, 2003 appeared to produce storm-time TEC exceeding quiet time values by a factor of 5 within 2\textendash3\ h of storm onset, at 1300\ LT. The physical cause of these large positive phase ionospheric storms is usually attributed to prompt penetration electric fields (PPEFs) initiated by Region 1 current closure through the ionosphere ( Nopper and Carovillano, 1978 mechanism). An unresolved question is what determines variation of the TEC response for different superstorms. It has been suggested that the cross polar cap potential and Region 1 currents are significant factors in determining PPEF in the equatorial ionosphere, which are related to the solar wind reconnection electric field estimated by Kan\textendashLee and others. In this paper, we show evidence that suggests By may be a significant factor controlling the TEC response during the main phase of superstorms. We analyzed the interplanetary conditions during the period that TEC was increasing for eight superstorms. We find that increasing daytime TEC during superstorms only occurs for large reconnection electric fields when By magnitude is less than Bz. The data suggest that Bz is a far more important factor in the TEC response than the reconnection electric field. We also find that TEC decreases following its peak storm-time value for two superstorms, even though Bz remains large and By magnitudes are less than Bz. Such decreases during the geomagnetic disturbance may indicate the role of magnetospheric shielding currents, or of changes in the thermosphere that have developed over the prolonged period of large solar wind electric field. Further analysis is warranted covering a wider range of storm intensities on the role of By in affecting the daytime TEC response for a range of storm intensities.

Mannucci, A.J.; Crowley, G.; Tsurutani, B.T.; Verkhoglyadova, O.P.; Komjathy, A.; Stephens, P.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 08/2014

YEAR: 2014     DOI: 10.1016/j.jastp.2014.01.001

Geomagnetic storms; Ionosphere

Ionospheric TEC, thermospheric cooling and $\Sigma$ [O/N2] compositional changes during the 6--17 March 2012 magnetic storm interval (CAWSES II)

A series of four geomagnetic storms (the minimum SYM-H~-148\ nT) occurred during the March 6\textendash17, 2012 in the ascending phase of the solar cycle 24. This interval was selected by CAWSES II for its campaign. The GPS total electron content (TEC) database and JPL\textquoterights Global Ionospheric Maps (GIM) were used to study vertical TEC (VTEC) for different local times and latitude ranges. The largest response to geomagnetic activity is shown in increases of the low-latitude dayside VTEC. Several GPS sites feature post-afternoon VTEC \textquotedblleftbite-outs\textquotedblright. During Sudden Impulse (SI+) event on March 8th a peak daytime VTEC restores to about quiet-time values. It is shown that the TIMED/SABER zonal flux of nitric oxide (NO) infrared cooling radiation correlates well with auroral heating. A factor of ~5 cooling increase is noted in some storms. The cooling radiation intensifies in the auroral zone and spreads towards the equator. Effects of the storm appear at lower latitudes ~18.6\ h later. The column density ratio Σ[O/N2] is analyzed based on TIMED/GUVI measurements. Both increases (at low latitudes) and decreases (from auroral to middle latitudes) in the ratio occurs during the geomagnetic storms. We suggest that the column density ratio could be enhanced at low to middle latitudes on the dayside partially due to the superfountain effect (atomic oxygen uplift due to ion-neutral drag). It is suggested that decreases in the Σ[O/N2] ratio at high to middle-latitudes may be caused by high thermospheric temperatures. During SI+s, there is an increase in Σ[O/N2] ratio at auroral latitudes.

Verkhoglyadova, O.P.; Tsurutani, B.T.; Mannucci, A.J.; Mlynczak, M.G.; Hunt, L.A.; Paxton, L.J.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 08/2014

YEAR: 2014     DOI: 10.1016/j.jastp.2013.11.009

Geomagnetic storms; Ionosphere; thermosphere

Solar filament impact on 21 January 2005: Geospace consequences

On 21 January 2005, a moderate magnetic storm produced a number of anomalous features, some seen more typically during superstorms. The aim of this study is to establish the differences in the space environment from what we expect (and normally observe) for a storm of this intensity, which make it behave in some ways like a superstorm. The storm was driven by one of the fastest interplanetary coronal mass ejections in solar cycle 23, containing a piece of the dense erupting solar filament material. The momentum of the massive solar filament caused it to push its way through the flux rope as the interplanetary coronal mass ejection decelerated moving toward 1 AU creating the appearance of an eroded flux rope (see companion paper by Manchester et al. (2014)) and, in this case, limiting the intensity of the resulting geomagnetic storm. On impact, the solar filament further disrupted the partial ring current shielding in existence at the time, creating a brief superfountain in the equatorial ionosphere\textemdashan unusual occurrence for a moderate storm. Within 1 h after impact, a cold dense plasma sheet (CDPS) formed out of the filament material. As the interplanetary magnetic field (IMF) rotated from obliquely to more purely northward, the magnetotail transformed from an open to a closed configuration and the CDPS evolved from warmer to cooler temperatures. Plasma sheet densities reached tens per cubic centimeter along the flanks\textemdashhigh enough to inflate the magnetotail in the simulation under northward IMF conditions despite the cool temperatures. Observational evidence for this stretching was provided by a corresponding expansion and intensification of both the auroral oval and ring current precipitation zones linked to magnetotail stretching by field line curvature scattering. Strong Joule heating in the cusps, a by-product of the CDPS formation process, contributed to an equatorward neutral wind surge that reached low latitudes within 1\textendash2 h and intensified the equatorial ionization anomaly. Understanding the geospace consequences of extremes in density and pressure is important because some of the largest and most damaging space weather events ever observed contained similar intervals of dense solar material.

Kozyra, J.; Liemohn, M.; Cattell, C.; De Zeeuw, D.; Escoubet, C.; Evans, D.; Fang, X.; Fok, M.-C.; Frey, H.; Gonzalez, W.; Hairston, M.; Heelis, R.; Lu, G.; Manchester, W.; Mende, S.; Paxton, L.; Rastaetter, L.; Ridley, A.; Sandanger, M.; Soraas, F.; Sotirelis, T.; Thomsen, M.; Tsurutani, B.; Verkhoglyadova, O.;

Published by: Journal of Geophysical Research: Space Physics      Published on: 07/2014

YEAR: 2014     DOI: 10.1002/2013JA019748

cold dense plasma sheet; Equatorial anomaly; magnetotail; precipitation; prompt penetration electric field; solar filament

Correction of astigmatism and coma using analytic theory of aberrations in imaging spectrometer based on concentric off-axis dual reflector system

A specific imaging spectrometer based on a concentric off-axis dual reflector system is proposed, free of astigmatism and coma. The described imaging spectrometer consists of four spherical mirrors and a plane grating. The analytic theory of aberrations and the optical path-length concept are used to derive the astigmatism elimination and coma removal. It is shown that the astigmatism in these imaging spectrometers is eliminated by characterizing three angles, and the coma is corrected when unequal mirror radii are configured in collimating and condensing optics. The developed aberration principle is verified by comparing the performance of the astigmatism-eliminated spectrometer with the spectrometer which has neither astigmatism nor coma.

Chen, Ting; Tang, Yi; Zhang, Li; Chang, Yue; Zheng, Cheng;

Published by: Applied Optics      Published on: 01/2014

YEAR: 2014     DOI: 10.1364/AO.53.000565

2013

Variability of ionospheric TEC during solar and geomagnetic minima (2008 and 2009): external high speed stream drivers

We study solar wind\textendashionosphere coupling through the late declining phase/solar minimum and geomagnetic minimum phases during the last solar cycle (SC23) \textendash 2008 and 2009. This interval was characterized by sequences of high-speed solar wind streams (HSSs). The concomitant geomagnetic response was moderate geomagnetic storms and high-intensity, long-duration continuous auroral activity (HILDCAA) events. The JPL Global Ionospheric Map (GIM) software and the GPS total electron content (TEC) database were used to calculate the vertical TEC (VTEC) and estimate daily averaged values in separate latitude and local time ranges. Our results show distinct low- and mid-latitude VTEC responses to HSSs during this interval, with the low-latitude daytime daily averaged values increasing by up to 33 TECU (annual average of ~20 TECU) near local noon (12:00 to 14:00 LT) in 2008. In 2009 during the minimum geomagnetic activity (MGA) interval, the response to HSSs was a maximum of ~30 TECU increases with a slightly lower average value than in 2008. There was a weak nighttime ionospheric response to the HSSs. A well-studied solar cycle declining phase interval, 10\textendash22 October 2003, was analyzed for comparative purposes, with daytime low-latitude VTEC peak values of up to ~58 TECU (event average of ~55 TECU). The ionospheric VTEC changes during 2008\textendash2009 were similar but ~60\% less intense on average. There is an evidence of correlations of filtered daily averaged VTEC data with Ap index and solar wind speed.

We use the infrared NO and CO2 emission data obtained with SABER on TIMED as a proxy for the radiation balance of the thermosphere. It is shown that infrared emissions increase during HSS events possibly due to increased energy input into the auroral region associated with HILDCAAs. The 2008\textendash2009 HSS intervals were ~85\% less intense than the 2003 early declining phase event, with annual averages of daily infrared NO emission power of ~ 3.3 \texttimes 1010 W and 2.7 \texttimes 1010 W in 2008 and 2009, respectively. The roles of disturbance dynamos caused by high-latitude winds (due to particle precipitation and Joule heating in the auroral zones) and of prompt penetrating electric fields (PPEFs) in the solar wind\textendashionosphere coupling during these intervals are discussed. A correlation between geoeffective interplanetary electric field components and HSS intervals is shown. Both PPEF and disturbance dynamo mechanisms could play important roles in solar wind\textendashionosphere coupling during prolonged (up to days) external driving within HILDCAA intervals.

Verkhoglyadova, O.; Tsurutani, B.; Mannucci, A.; Mlynczak, M.; Hunt, L.; Runge, T.;

Published by: Annales Geophysicae      Published on: 01/2013

YEAR: 2013     DOI: 10.5194/angeo-31-263-2013

Ionosphere; Magnetospheric physics; Storms; substorms

Retrieving ionospheric electron density profile from FUV spectral remote sensing measurements

WANG, Jing; Tang, Yi; ZHANG, Zhi-Ge; ZHENG, Xu-Li; Ni, Guo-qiang;

Published by: Chinese Journal of Geophysics      Published on:

YEAR: 2013     DOI:

A Quality Assessment Method for Retrieved O/N\_2 Images from FUV Remote Sensing

WANG, Jing; Tang, Yi; Peng, Sheng-feng; ZHENG, Xu-Li; Ni, Guo-qiang;

Published by: Infrared      Published on:

YEAR: 2013     DOI:

Comparison of Ionospheric and Thermospheric Effects During Two High Speed Stream Events

Verkhoglyadova, OP; Tsurutani, B; Mannucci, AJ; Paxton, L; Mlynczak, MG; Hunt, LA; Echer, E;

Published by:       Published on:

YEAR: 2013     DOI:

2012

Research on Retrieving Thermospheric O/N2 from FUV Remote Sensing

Magnetic storms usually cause significant departures of thermospheric O and N2\ from their normal values. To study the effects on thermospheric neutral species caused by magnetic storms, a method to retrieve thermospheric O/N2\ based on the data obtained from global ultraviolet imager on board TIMED is presented. With the help of AURIC, the normalizations of observing angles and SZAs were preformed to the measurements and a relationship between 135.6/LBHs and O/N2\ was established. Finally, applying the proposed method to retrieve O/N2\ during a magnetic period(29, September\textemdash4, October, 2002), it was shown that magnetic storms could induce significant O/N2\ depletion, extending from the polar regions towards the equator.

Peng, S.; Tang, Y.; Wang, J.; Zheng, X.;

Published by: Spectroscopy and Spectral Analysis      Published on: 05/2012

YEAR: 2012     DOI: 10.3964/j.issn.1000-0593(2012)05-1296-05

AURIC; GUVI; Magnetic storm; O/N2

2011

Ionospheric VTEC and thermospheric infrared emission dynamics during corotating interaction region and high-speed stream intervals at solar minimum: 25 March to 26 April 2008

Verkhoglyadova, O.; Tsurutani, B.; Mannucci, A.; Mlynczak, M.; Hunt, L.; Komjathy, A.; Runge, T.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2011

YEAR: 2011     DOI: 10.1029/2011JA016604

2010

Direct measurements of the Poynting flux associated with convection electric fields in the magnetosphere

Nishimura, Y.; Kikuchi, T.; Shinbori, A.; Wygant, J.; Tsuji, Y.; Hori, T.; Ono, T.; Fujita, S.; Tanaka, T.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2010

YEAR: 2010     DOI: 10.1029/2010JA015491

Radar, lidar, and optical observations in the polar summer mesosphere shortly after a space shuttle launch

Kelley, M.; Nicolls, M.; Varney, R.; Collins, R.; Doe, R.; Plane, J.; Thayer, J.; Taylor, M.; Thurairajah, B.; Mizutani, K.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2010

YEAR: 2010     DOI: 10.1029/2009JA014938

The ground calibration of far ultraviolet scanning imaging spectrometer (FUSIS)

The far ultraviolet scanning imaging spectrometer (FUSIS) is used to measure the composition and distribution of the main molecules and atoms in the Earth s upper atmosphere. It is an important instrument in investigation of the physical and chemical processes in the Earth s upper atmosphere. FUSIS works between 120nm to 180nm, its spectral resolution is better than 1.0nm and its spatial resolution is 8 pixels. This paper describes a kind of ground calibration method and facility of FUSIS. The FUV light is invisible, so all works must be done in high vacuum.

Wu, Yan; Tang, Yi; Liu, Jianpeng; Zhang, Zhige; Ni, Guoqiang;

Published by:       Published on:

YEAR: 2010     DOI: 10.1117/12.870475

2009

Local time dependence of the prompt ionospheric response for the 7, 9, and 10 November 2004 superstorms

We investigate the effects of penetration electric fields, meridional thermospheric neutral winds, and composition perturbation zones (CPZs) on the distribution of low-latitude plasma during the 7\textendash11 November 2004 geomagnetic superstorm. The impact on low-latitude plasma was assessed using total electron content (TEC) measurements from a latitudinally distributed array of ground-based GPS receivers in South America. Jicamarca Radio Observatory incoherent scatter radar measurements of vertical E\texttimesB drift are used in combination with the Low-Latitude IONospheric Sector (LLIONS) model to examine how penetration electric fields and meridional neutral winds shape low-latitude TEC. It is found that superfountain conditions pertain between \~1900 and 2100UT on 9 November, creating enhanced equatorial ionization anomaly (EIA) crests at \textpm20\textdegree geomagnetic latitude. Large-amplitude and/or long-duration changes in the electric field were found to produce significant changes in EIA plasma density and latitudinal location, with a delay time of \~2\textendash2.5h. Superfountain drifts were primarily responsible for EIA TEC levels; meridional winds were needed only to create hemispherical crest TEC asymmetries. The [O/N2] density ratio (derived from the GUVI instrument, flown on the TIMED satellite) and measurements of total atmospheric density (from the GRACE satellites), combined with TEC measurements, yield information regarding a likely CPZ that appeared on 10 November, suppressing TEC for over 16h.

Mannucci, Anthony; Tsurutani, Bruce; Kelley, Michael; Iijima, Byron; Komjathy, Attila;

Published by: Journal of Geophysical Research      Published on: Jan-01-2009

YEAR: 2009     DOI: 10.1029/2009JA014043

Near Earth space plasma monitoring under COST 296

This review paper presents the main achievements of the near Earth space plasma monitoring under COST 296

Action. The outputs of the COST 296 community making data, historical and real-time, standardized and available\ to the ionospheric community for their research, applications and modeling purposes are presented. The contribution\ of COST 296 with the added value of the validated data made possible a trusted ionospheric monitoring\ for research and modeling purposes, and it served for testing and improving the algorithms producing real-time

data and providing data users measurement uncertainties. These value added data also served for calibration and

validation of space-borne sensors. New techniques and parameters have been developed for monitoring the near\ Earth space plasma, as time dependent 2D maps of vertical total electron content (vTEC), other key ionospheric\ parameters and activity indices for distinguishing disturbed ionospheric conditions, as well as a technique for improving\ the discrepancies of different mapping services. The dissemination of the above products has been developed\ by COST 296 participants throughout the websites making them available on-line for real-time applications.

Altadill, D.; Boska, J.; Cander, L.; Gulyaeva, T.; Reinisch, B.; Romano, V.; Krankowski, A.; Bremer, J.; Belehaki, A.; Stanislawska, I.; Jakowski, N.; Scotto, C.;

Published by: Annals of Geophysics      Published on: 06/2009

YEAR: 2009     DOI:

Retrieval of ionospheric O/N2 based on FUV imaging data

Solar storms in the ionosphere have a great impact on human\textquoterights life. It\textquoterights of great significance to find an effective way for an accurate prediction of solar storms. In this paper, we present a method based on GUVI FUV day-glow imaging data to derive O/N2, an environmental parameter used to forecast Space Weather. In the retrieval, we selected two channels of the FUV wavelengths, OI135.6nm and LBH2. In accordance with the linear relationship between O/N2 and 135.6/LBH, we proposed 135.6/LBH to describe O/N2. With the method described in this paper, the data of a 4-day solar storm, October 1 to 4, 2002, have been processed. Subsequently, the obtained O/N2 maps were in good agreement with previous results. It demonstrated the retrieval process we put up is efficient.

Jing, Wang; Tang, Yi; Tang, Li-jun; Ni, Guo-qiang;

Published by:       Published on:

YEAR: 2009     DOI: 10.1117/12.833985

Retrieval of ionospheric O/N2 based on FUV imaging data

Solar storms in the ionosphere have a great impact on human\textquoterights life. It\textquoterights of great significance to find an effective way for an accurate prediction of solar storms. In this paper, we present a method based on GUVI FUV day-glow imaging data to derive O/N2, an environmental parameter used to forecast Space Weather. In the retrieval, we selected two channels of the FUV wavelengths, OI135.6nm and LBH2. In accordance with the linear relationship between O/N2 and 135.6/LBH, we proposed 135.6/LBH to describe O/N2. With the method described in this paper, the data of a 4-day solar storm, October 1 to 4, 2002, have been processed. Subsequently, the obtained O/N2 maps were in good agreement with previous results. It demonstrated the retrieval process we put up is efficient.

Jing, Wang; Tang, Yi; Tang, Li-jun; Ni, Guo-qiang;

Published by:       Published on:

YEAR: 2009     DOI: 10.1117/12.833985

Design of FUV imaging spectrometer based on crossed Czerny-Turner structure

This article describes the characteristics of the far ultraviolet (FUV) radiation and its applications in the space weather s research and prediction. The FUV imaging spectrometer is irreplaceable to get the FUV radiation data of the earth s upper atmosphere. Some key technologies of FUV spectrometer are analyzed respectively, including window materials, FUV light source, FUV detectors and FUV coating, which offer theoretical foundation for FUV imaging spectrometer. The paper presents a FUV band imaging spectrometer s optical system which is based on crossed Czerny-Turner structure with all reflective components in it. The wavelength range of the FUV spectrometer optical system is from 100nm to 200nm and the initial structure is simulated and optimized by Zemax in order to improve the spectral resolution. The theoretical spectral resolution of the system is better than 1nm, and it has a certain imaging capacity.

Wu, Yan; Tang, Yi; Ni, Guoqiang; Sheng, Yunlong; Wang, Yongtian; Zeng, Lijiang;

Published by:       Published on:

YEAR: 2009     DOI: 10.1117/12.806967

space weather; far ultraviolet; Imaging spectrometer; crossed Czerny-Turner system; optical design

Retrieval of ionospheric O/N2 based on FUV imaging data

Jing, Wang; Tang, Yi; Tang, Li-jun; Ni, Guo-qiang;

Published by:       Published on:

YEAR: 2009     DOI:

Retrieval of ionospheric O/N2 based on FUV imaging data

Jing, Wang; Tang, Yi; Tang, Li-jun; Ni, Guo-qiang;

Published by:       Published on:

YEAR: 2009     DOI:

2008

XUV Photometer System (XPS): Improved Solar Irradiance Algorithm Using CHIANTI Spectral Models

Woods, Thomas; Chamberlin, Phillip; Peterson, W.; Meier, R.; Richards, Phil; Strickland, Douglas; Lu, Gang; Qian, Liying; Solomon, Stanley; Iijima, B.; Mannucci, A.; Tsurutani, B.;

Published by: Solar Physics      Published on: Jan-08-2008

YEAR: 2008     DOI: 10.1007/s11207-008-9196-6

Seasonal variation of the longitudinal structure of the equatorial ionosphere: Does it reflect tidal influences from below?

Liu, Huixin; Watanabe, Shigeto;

Published by: Journal of Geophysical Research      Published on: Jan-01-2008

YEAR: 2008     DOI: 10.1029/2008JA013027

Satellite and ground-based observations of auroral energy deposition and the effects on thermospheric composition during large geomagnetic storms: 1. Great geomagnetic storm of 20 November 2003

Hecht, JH; Mulligan, T; Strickland, DJ; Kochenash, AJ; Murayama, Y; Tanaka, Y-M; Evans, DS; Conde, MG; Donovan, EF; Rich, FJ; , others;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2008     DOI:

F3 layer during penetration electric field

The occurrence of an additional layer, called F3 layer, in the equatorial ionosphere at American, Indian, and Australian longitudes during the super double geomagnetic storm of 7–11 November 2004 is presented using observations and modeling. The observations show the occurrence, reoccurrence, and quick ascent to the topside ionosphere of unusually strong F3 layer in Australian longitude during the first super storm (8 November) and in Indian longitude during the second super storm (10 November), all with large reductions in peak electron density (Nmax) and total electron content (GPS-TEC). The unusual F3 layers can arise mainly from unusually strong fluctuations in the daytime vertical E × B drift as indicated by the observations and modeling in American longitude. The strongest upward E × B drift (or eastward prompt penetration electric field, PPEF) ever recorded (at Jicamarca) produces unusually strong F3 layer in the afternoon hours (≈1400–1600 LT) of PPEF, with large reductions in Nmax and TEC; the layer also reappears in the following evening (≈1700–1800 LT) owing to an unusually large downward drift. At night, when the drift is unusually upward and strong, the F region splits into two layers.

Balan, N.; Thampi, S.; Lynn, K.; Otsuka, Y.; Alleyne, H.; Watanabe, S.; Abdu, M.; Fejer, B.;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2008     DOI: https://doi.org/10.1029/2008JA013206

F3 layer; penetration; Electric field

Subauroral polarization streams: Observations with the Hokkaido and King Salmon SuperDARN radars and modeling

Koustov, Alexandre; Nishitani, Nozomu; Ebihara, Y; Kikuchi, T; Hairston, M.R.; Andre, D.;

Published by:       Published on:

YEAR: 2008     DOI:

2007

Dynamic variations of a convection flow reversal in the subauroral postmidnight sector as seen by the SuperDARN Hokkaido HF radar

Kataoka, Ryuho; Nishitani, Nozomu; Ebihara, Yusuke; Hosokawa, Keisuke; Ogawa, Tadahiko; Kikuchi, Takashi; Miyoshi, Yoshizumi;

Published by: Geophysical Research Letters      Published on: Jan-01-2007

YEAR: 2007     DOI: 10.1029/2007GL031552

Correction of SOHO CELIAS/SEM EUV measurements saturated by extreme solar flare events

Didkovsky, LV; Judge, DL; Jones, AR; Wieman, S; Tsurutani, BT; McMullin, D;

Published by: Astronomische Nachrichten: Astronomical Notes      Published on:

YEAR: 2007     DOI:

2006

Kelvin-Helmholtz instability in a magnetotail flank-like geometry: Three-dimensional MHD simulations

Takagi, K; Hashimoto, C; Hasegawa, H; Fujimoto, M; TanDokoro, R;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2006     DOI:



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