Article
Geosciences, Multidisciplinary
Yu Lin, Xueyi Wang, David G. Sibeck, Chih-Ping Wang, Sun-Hee Lee
Summary: This study conducts a three-dimensional global hybrid simulation to investigate the interaction between the Earth's bow shock and an interplanetary directional tangential discontinuity. The results reveal that a hot flow anomaly is generated only in the southern hemisphere, driven by the reversal in the north-south component of reflected ion velocities.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
Andrew Vu, Terry Z. Liu, Hui Zhang, Craig Pollock
Summary: Research has found that foreshock transients display heated, tenuous cores and large flow deflections. The availability of higher resolution data has allowed for closer examinations of these substructures. Statistical studies have shown that the occurrence rates of the event types are correlated with magnetic field strength, solar wind speed, and Mach numbers. The presence of substructures is associated with longer core durations and larger sizes, as well as positive correlations with bulk flows and negative correlations with temperatures. The size of the substructures varies, suggesting multiple formation mechanisms.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Geosciences, Multidisciplinary
Z-Y Liu, Q-G Zong, H. Zhang, J. T. Zhao, R. Rankin, C. J. Pollock, G. Le
Summary: This study investigates a shocklet observed in the Earth's foreshock and reveals the occurrence of cyclotron resonance between the shocklet and solar wind (SW) ions. The observations suggest that the cyclotron resonance provides a mechanism for shocklet dissipation and SW ion energization.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Hakon Midthun Kolsto, Cecilia Norgren, Michael Hesse, Li-Jen Chen, Paul Tenfjord, Susanne Flo Spinnangr, Norah Kwagala
Summary: Heavier plasma species such as oxygen ions can have a significant impact on magnetic reconnection, with the acceleration of oxygen ions possibly leading to the formation of an expanding oxygen wave. Observational evidence from NASA's Magnetospheric Multiscale mission and kinetic simulations show characteristics of this wave, including a cold ion jet and a density cavity associated with the neutral sheet. These results are crucial for understanding the role and effects of oxygen ions in magnetic reconnection.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Petroleum
Wei Li, Zhaoyi Dai, Xin Wang, Saebom Ko, Samiridhdi Paudyal, Xuanzhu Yao, Cianna Leschied, Yu-Yi Shen, Daniel Pimentel, Amy T. Kan, Mason Tomson
Summary: Aqueous CO2-containing environment in oil and gas production can lead to the formation of carbonate scales such as calcite, as well as corrosion-induced scales like siderite on mild steel surfaces. This study investigated the relationship between corrosion-induced scales and other metal carbonate scales on steel surfaces. It was found that a two-layer scale structure formed, with an inner layer of iron-containing carbonate scale (ankerite or siderite) and an outer layer of calcite. Furthermore, a common scale inhibitor was effective in mitigating scale formation but aggravated steel corrosion.
Article
Astronomy & Astrophysics
X. Tan, M. W. Dunlop, X. -c. Dong, Y. -y. Yang, Y. -s. Du, C. Shen, C. T. Russell, W. -l. Liu
Summary: We estimated the in situ current density of the Earth's ring current using the curlometer method and examined its morphology using the Magnetospheric Multiscale mission's high accuracy data. Statistical analysis of data from September 2015 to the end of 2016 revealed a near-equatorial morphology of the ring current in terms of radial distance and magnetic local time. We also discovered asymmetries in the inner and outer currents, suggesting peak and valley plasma pressure contributions.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
N. S. V. Lund, J. K. Kirstein, H. Madsen, O. Mark, P. S. Mikkelsen, M. Borup
Summary: Smart meters measuring water consumption are being increasingly deployed worldwide. They provide detailed knowledge of wastewater inflow, but their data quality and uncertainties should be carefully considered. Urban drainage management may benefit from digital system integration despite potential obstacles.
JOURNAL OF HYDROINFORMATICS
(2021)
Article
Agronomy
Charalampos Doulgeris, Zacharenia Kypritidou, Vasiliki Kinigopoulou, Evangelos Hatzigiannakis
Summary: This study investigates the availability of potassium in soil enriched with biochar under different moisture conditions, and examines two ion exchange approaches. The results show that potassium is released gradually under unsaturated flow conditions, while it is completely released over a few days under saturated flow conditions. The E.E. approach provides more soluble potassium for plant uptake compared to the K.E. approach. Increasing the proportion of biochar in the soil doubles the available potassium. Among the different modeling schemes, there is a significant variation in release time, indicating that simplified saturated conditions may lead to unrealistic estimates of nutrient availability. Further experimental work is needed to reduce the uncertainty in parameter estimation for the K.E. approach.
Article
Physics, Nuclear
Rajkumar Mondal, Nilanjan Chaudhuri, Snigdha Ghosh, Sourav Sarkar, Pradip Roy
Summary: This study investigates the azimuthal angle and transverse momentum dependence of dilepton production from hot and magnetized hadronic matter. The results show that in the low invariant mass region, there are significant contributions from the finite background field, leading to an anisotropic emission rate of the dileptons. Additionally, it is found that the production rate of dileptons may be larger along the direction transverse to the background field in the low invariant mass region.
EUROPEAN PHYSICAL JOURNAL A
(2023)
Article
Geosciences, Multidisciplinary
X. Ma, A. M. Tian, Q. Q. Shi, S. C. Bai, S. T. Yao, X. C. Shen, W. J. Sun, R. L. Guo, M. Nowada, A. W. Degeling, J. Liu, L. Li, S. Zhang, W. Li
Summary: Based on THEMIS observations, electron pitch angle distributions (ePADs) in the troughs of compressional Pc5 waves are classified into three types: cigar, butterfly, and pancake, associated with whistler-mode waves and drift-shell splitting effect. These statistical features provide insights into the energy conversion and regulation of charged particles in the magnetosphere.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Astronomy & Astrophysics
Stefan Eriksson, Xuanye Ma, James L. Burch, Antonius Otto, Scot Elkington, Peter A. Delamere
Summary: On September 8, 2015, the MMS satellites encountered a Kelvin-Helmholtz instability at the post-noon flank magnetopause. The adjacent magnetosheath exhibited a predominantly northward magnetic field, with ion velocity distribution functions indicating at least 17 KH vortex intervals.
FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
(2021)
Article
Astronomy & Astrophysics
F. Becattini, M. Buzzegoli, A. Palermo, G. Prokhorov
Summary: In this study, a method for measuring chirality imbalance in relativistic nuclear collisions using the helicity of final state baryons is proposed. The method does not require coupling to the electromagnetic field like the Chiral Magnetic Effect. It is shown that in the presence of chirality imbalance, spin 1/2 baryons and anti-baryons receive an additional contribution to their polarization along their momentum direction, which can be detected through studying azimuthal angular correlation.
Article
Chemistry, Multidisciplinary
Pavel Navratil, Libor Pekar, Radek Matusu, Mengjie Song, Qingbin Gao, Shanti S. Kandala, Ondrej Kadlcik
Summary: The paper focuses on the identification, control design, and experimental verification of a two-input two-output hot-air laboratory apparatus. A decentralized multivariable controller design is proposed, achieving control-loop decoupling and measurable disturbance rejection. The laboratory experiments demonstrate better temperature control performance, energy consumption reduction, and control effort improvement compared to traditional design strategies.
Article
Astronomy & Astrophysics
Andrew Vu, Terry Z. Liu, Hui Zhang, Peter Delamere
Summary: This study investigates the formation of foreshock bubbles (FBs) and hot flow anomalies (HFAs) in the magnetosphere-ionosphere system. The thickness of the tangential discontinuity (TD) determines the type of foreshock transient that forms. A thin TD leads to the formation of an FB with one upstream compressional boundary, while a thick TD results in the formation of an HFA with two compressional boundaries. The study confirms a recently proposed kinetic formation model.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Chris Fox, Paul Wiegert
Summary: The Near Earth Object Surveillance Satellite (NEOSSat) is an Earth-orbiting telescope that can be used to observe asteroids near the Sun and exoplanetary transits of bright stars. By using NEOSSat, we were able to perform followup observations of Transiting Exoplanets Survey Satellite (TESS) targets and recover/confirm the orbital properties, showcasing NEOSSat as a valuable contributor to exoplanetary science.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Andrew Vu, Terry Z. Z. Liu, Hui Zhang, Peter Delamere
Summary: This study uses 2-D local hybrid simulations to investigate the effects of different foreshock ion distributions and properties on the growth of tangential discontinuity-driven foreshock bubbles (FBs). It is found that for a gyrophase-bunched distribution, where the initial phase is on the other side of the tangential discontinuity, more foreshock ions cross the discontinuity, leading to a faster expansion compared to a Maxwellian distribution. A ring distribution also results in higher expansion speeds due to greater projected velocity. For Maxwellian distributions, there are positive and linear correlations between the FB expansion speeds and initial foreshock ion densities, thermal speeds, parallel speeds, and sine of the tangential discontinuity magnetic shear angles. These parameter dependencies become stronger as the structures evolve with time. Foreshock ion distributions and properties that generate stronger currents produce more significant magnetic field variations and higher expansion speeds.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Terry Z. Liu, Andrew Vu, Hui Zhang, Xin An, Vassilis Angelopoulos
Summary: Foreshock transients, such as hot flow anomalies (HFAs) and foreshock bubbles (FBs), can disturb the bow shock and influence the magnetosphere and ionosphere. This study establishes a predictive model for the expansion speed of FBs and validates it through simulations and observations. The results provide a foundation for predicting the formation and expansion of foreshock transients, ultimately allowing for forecast of their space weather effects and particle acceleration.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Yi Qi, Robert Ergun, Neha Pathak, Tak Chu Li, Stefan Eriksson, Alexandros Chasapis, Steven J. Schwartz, Narges Ahmadi, Tien Vo, David Newman, Maria Usanova, Frederick D. Wilder, Jason Shuster
Summary: Magnetic reconnection, a fundamental plasma process, has been extensively studied using various methods. Recent observations have challenged the traditional understanding of magnetic reconnection by showing that the X-line, which is believed to be perpendicular to the reconnection plane, can be nonorthogonal. This study presents a second nonorthogonal X-line event, supporting the idea that this phenomenon is not an aberration.
ASTROPHYSICAL JOURNAL
(2023)
Article
Geosciences, Multidisciplinary
H. Madanian, N. Omidi, D. G. Sibeck, L. Andersson, R. Ramstad, S. Xu, J. R. Gruesbeck, S. J. Schwartz, R. A. Frahm, D. A. Brain, P. Kajdic, F. G. Eparvier, D. L. Mitchell, S. M. Curry
Summary: This study investigates the non-planarity of Mars' bow shock and its impact on transient structures near the upstream edge of moving foreshocks caused by slow rotations in the IMF. The structures exhibit a decrease in plasma density and IMF strength within their core, accompanied by a compressional shock layer, consistent with foreshock bubbles. The ion populations responsible for these structures include backstreaming ions and reflected ions with hybrid trajectories.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Astronomy & Astrophysics
J. Goldstein, J. L. Burch, S. A. Fuselier, R. Gomez, C. A. Gonzalez, M. J. Kim, J. Mukherjee, N. E. Turner, M. E. Wilson
Summary: This study provides a comprehensive statistical analysis of several distinct populations of warm ions in the magnetospheric plasma environment. It reveals the characteristics and compositions of these warm ions, which contributes to a better understanding of the magnetospheric plasma environment. Two known populations of warm ions, the warm plasmasphere and the warm cloak/trough, are identified and characterized.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
M. J. Kim, J. Goldstein, S. A. Fuselier, A. Glocer, J. L. Burch
Summary: Field-aligned distributions of low-energy H+ ions in the magnetosphere originate from the ionosphere, and recent studies have reported an interhemispheric asymmetry in this ion outflow. In this study, we investigate a case study of asymmetric field-aligned distributions resulting from asymmetric outflow observed on 13 August 2019. The results show that there is a stronger outflow from the southern hemisphere, which is consistent with enhanced ionospheric parameters and electron precipitation fluxes in that hemisphere.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Terry Z. Liu, Andrew Vu, Vassilis Angelopoulos, Hui Zhang
Summary: When a solar wind discontinuity interacts with foreshock ions, it can create hot flow anomalies and foreshock bubbles, which disturb the bow shock, magnetopause, and magnetosphere-ionosphere system. However, these phenomena are currently unpredictable. In this study, we derived equations to analyze the motion of foreshock ions around a discontinuity and the resulting current density. By using these equations, we developed a model to predict the energy conversion and expansion of the solar wind plasma away from the discontinuity. Our results show that this model is successful in predicting significant dynamic pressure disturbances caused by foreshock ion-discontinuity interactions, and we discuss ways to improve it in the future.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
H. Hasegawa, R. E. Denton, K. Dokgo, K. -J Hwang, T. K. M. Nakamura, J. L. Burch
Summary: This study analyzes three flux transfer events (FTEs) and subsequent crossing of a reconnecting magnetopause current sheet (MPCS) observed by the Magnetospheric Multiscale spacecraft. The aim is to understand the generation mechanism of ion-scale magnetic flux ropes (ISFRs) and their relationship with electromagnetic energy conversion and kinetic processes. The results show that ISFRs can be generated through secondary reconnection in an electron-scale current sheet (ECS), and the FTEs also formed through the same secondary reconnection process. Observations also suggest complex magnetic topology and localized conversion of electromagnetic to electron energy in the ISFR.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Y. C. Zhang, C. Wang, L. Dai, S. Y. Tang, J. L. Burch
Summary: The process of magnetic reconnection in plasma changes the magnetic field configuration and releases magnetic energy explosively. During magnetic reconnection events, the asymptotic magnetic field lines can be strictly antiparallel or have only one antiparallel component, leading to distinct reconnection features. This study provides observational evidence for the existence of a strong out-of-plane magnetic field at the X-line in antiparallel reconnection. The strong out-of-plane magnetic field significantly alters the diffusion region's structure and influences the reconnection features, including particle dynamics and energy dissipation through a guide field.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Terry Z. Liu, Vassilis Angelopoulos, Andrew Vu, Hui Zhang
Summary: In the ion foreshock, hot flow anomalies (HFAs) and foreshock bubbles (FBs) are two types of foreshock transients that have significant fluctuations. They are formed due to the interaction between foreshock ions and solar wind discontinuities. The direction of the foreshock ion-driven current and the changes in magnetic field strength behind the discontinuity determine the formation of these transients. This study aims to predict the formation of HFAs and FBs by deriving analytical equations to estimate the foreshock ion-driven current direction.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
D. Teubenbacher, O. W. Roberts, R. Nakamura, Y. Narita, Z. Voeroes, K. Torkar, P. -A. Lindqvist, R. E. Ergun
Summary: In this study, the Magnetospheric Multiscale (MMS) mission data is utilized to estimate electron density and analyze compressive turbulence in the Earth's magnetosheath. The MMS Solar Wind Turbulence Campaign in February 2019 provided multiple spacecraft measurements at varying distances for a detailed investigation. The derived electron density data has higher temporal resolution compared to plasma instruments, allowing examination of fluctuations at sub-ion scales. The findings suggest different drivers in the strongly compressive magnetosheath and the weakly compressive solar wind, with compressive structures potentially playing significant roles.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Xing-Yu Li, Qiu-Gang Zong, Jian-Jun Liu, Ze-Fan Yin, Ze-Jun Hu, Xu-Zhi Zhou, Chao Yue, Zhi-Yang Liu, Xing-Xin Zhao, Zi-Kang Xie, J. Bernard Blake, Christopher T. Russell, Robert E. Ergun, Per-Arne Lindqvist
Summary: This study conducted a comparative research on two pulsating aurora events and ULF waves, and found a correlation between pulsating auroras and ULF waves. The physical mechanisms behind this correlation differ in different events. The ULF waves may originate from perturbations in the solar wind and play a significant role in the solar wind-magnetosphere-ionosphere coupling, but further study is needed.
Article
Astronomy & Astrophysics
Z. C. Tian, M. Zhou, H. Y. Man, Z. H. Zhong, X. H. Deng, D. J. Gershman, Y. V. Khotyaintsev, C. T. Russell
Summary: This paper presents the simultaneous observation of the inner and outer electron diffusion region (EDR) in magnetic reconnection with a large guide field at the dayside magnetopause by the magnetospheric multiscale (MMS) spacecraft. The inner EDR is characterized by positive J·E', while the outer EDR is manifested by negative J·E' and opposite out-of-plane electric field. The observation of bidirectional accelerated electron jets on the opposite side of the X-line is significant, and the fortuitous formation of MMS provides estimates for the length of the inner EDR and the reconnection rate.
ASTROPHYSICAL JOURNAL
(2023)
Article
Geosciences, Multidisciplinary
Tongkuai Li, Wenya Li, Binbin Tang, Yuri. V. Khotyaintsev, Daniel Bruce Graham, Akhtar Ardakani, J. L. Burch, D. J. Gershman, B. Lavraud, C. T. Russell, Quanming Lu, Xiaocheng Guo, Chi Wang
Summary: This study presents Magnetospheric Multiscale (MMS) observations of a K-H wave event accompanied by ongoing magnetic reconnection under southward IMF conditions. The nonlinear K-H waves exhibit quasi-periodic fluctuations, presence of low-density and high-speed ions, and variations in the boundary normal vectors. Through the identification of Alfvenic ion jets and the escape of energetic magnetospheric electrons, clear evidence of on-going magnetic reconnection is revealed. Notably, out of the 36 magnetopause current-sheet crossings in this event, 19 exhibit unambiguous signatures of reconnection at both the leading and trailing edges, indicating the compression effect resulting from the large-scale evolution of the K-H waves.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Astronomy & Astrophysics
K. Llera, S. A. Fuselier, S. M. Petrinec, R. C. Rice, J. L. Burch, B. Giles, K. J. Trattner, R. J. Strangeway
Summary: We demonstrate that plasmaspheric/cold ions accelerated near the magnetopause boundary can simulate the local magnetopause motion and capture local structures such as waves on the boundary. By tracking cold ion velocities, it is possible to track magnetopause motion over a long period of time and study the evolution of boundary layer thickness and wave structures. This method can generally track magnetopause motion within a distance of about 1-2 RE from the spacecraft during steady space weather conditions.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)