Search Publications
Investigation of a W UMa-type contact binary GZ And in a physical triple system
Zheng, Jie; Jiang, Lin-Qiao
GZ And is a variable star within the visually observed multiple-star system ADS 1693. Recent observations have yielded new light curves for GZ And, obtained using the Xinglong 85-cm telescope and the Transiting Exoplanet Survey Satellite (TESS) satellite. These light curves, along with radial velocity curves, were analyzed simultaneously to ascert…
Unsteady Dungey cycle from the point of view of Stokes' theorem
Semenov, Vladimir S.; Kubyshkin, Igor V.; Tsyganenko, Nikolai A. +3 more
The Dungey cycle is considered from the formation of a magnetic barrier and necessary for dayside reconnection conditions till the electric field generation around the Birkeland current loop and magnetic flux circulation balance. Data-based modeling of the magnetosheath magnetic field makes it possible to quantitatively assess the main factors tha…
Interrogating Solar Flare Loop Models with IRIS Observations 2: Plasma Properties, Energy Transport, and Future Directions
Kerr, Graham S.
During solar flares a tremendous amount of magnetic energy is released and transported through the Sun's atmosphere and out into the heliosphere. Despite over a century of study, many unresolved questions surrounding solar flares are still present. Among those are how does the solar plasma respond to flare energy deposition, and what are the impor…
The evolving paradigm of the subauroral geospace
Mishin, Evgeny V.
An assessment of the status quo of fast subauroral flows—subauroral ion drifts (SAID) and subauroral polarization streams (SAPS), is presented. For a few decades, their development has been interpreted in terms of the voltage and current magnetospheric generators based largely on the drift motion of test particles. Recent multispacecraft observati…
Modeling of the cold electron plasma density for radiation belt physics
Merkin, V. G.; Pierrard, V.; Ukhorskiy, A. Y. +8 more
This review focusses strictly on existing plasma density models, including ionospheric source models, empirical density models, physics-based and machine-learning density models. This review is framed in the context of radiation belt physics and space weather codes. The review is limited to the most commonly used models or to models recently devel…
Mesoscale phenomena and their contribution to the global response: a focus on the magnetotail transition region and magnetosphere-ionosphere coupling
Wang, Chih-Ping; Nishimura, Yukitoshi; Malaspina, David +24 more
An important question that is being increasingly studied across subdisciplines of Heliophysics is "how do mesoscale phenomena contribute to the global response of the system?" This review paper focuses on this question within two specific but interlinked regions in Near-Earth space: the magnetotail's transition region to the inner magnetosphere an…
A prominence eruption from the Sun to the Parker Solar Probe with multi-spacecraft observations
Susino, Roberto; Andretta, Vincenzo; Landini, Federico +10 more
In the early hours of 2021 April 25, the Solar Probe Cup on board Parker Solar Probe registered the passage of a solar wind structure characterized by a clear and constant He2+/H+ density ratio above 6% during three hours. The He2+ contribution remained present but fainting and intermittent within a twelve-hour window. Solar Orbiter and Parker Sol…
Chromospheric thermodynamic conditions from inversions of complex Mg II h & k profiles observed in flares
De Pontieu, Bart; Sainz Dalda, Alberto
The flare activity of the Sun has been studied for decades, using both space- and ground-based telescopes. The former have mainly focused on the corona, while the latter have mostly been used to investigate the conditions in the chromosphere and photosphere. The Interface Region Imaging Spectrograph (IRIS) instrument has served as a gateway betwee…
Non-thermal Broadening of IRIS Fe XXI Line Caused by Turbulent Plasma Flows in the Magnetic Reconnection Region During Solar Eruptions
Reeves, Katharine K.; Polito, Vanessa; Chen, Bin +3 more
Magnetic reconnection is the key mechanism for energy release in solar eruptions, where the high-temperature emission is the primary diagnostic for investigating the plasma properties during the reconnection process. Non-thermal broadening of high-temperature lines has been observed in both the reconnection current sheet (CS) and flare loop-top re…
The evolution of our understanding of coronal mass ejections
Vourlidas, Angelos; Stenborg, Guillermo; Howard, Russell A.
The unexpected observation of a sudden expulsion of mass through the solar corona in 1971 opened up a new field of interest in solar and stellar physics. The discovery came from a white-light coronagraph, which creates an artificial eclipse of the Sun, enabling the viewing of the faint glow from the corona. This observation was followed by many mo…