Search Publications
Large Eruptive and Confined Flares in Relation to the Solar Active Region Evolution
Liu, Yu; Wang, Huaning; Rao, Changhui +5 more
Solar active regions (ARs) provide the required magnetic energy and the topology configuration for flares. Apart from conventional static magnetic parameters, the evolution of AR magnetic flux systems should have nonnegligible effects on magnetic energy store and the trigger mechanism of eruptions, which would promote the prediction for the flare …
The Plasma β in Quiet Sun Regions: Multi-instrument View
Veronig, Astrid; Podladchikova, Tatiana; Gömöry, Peter +4 more
A joint campaign of several spaceborne and ground-based observatories, such as the GREGOR solar telescope, the Extreme-ultraviolet Imaging Spectrometer (EIS), and the Interface Region Imaging Spectrograph (Hinode Observing Plan 381, 2019 October 11–22) was conducted to investigate the plasma β in quiet Sun regions. In this work, we focus on 2019 O…
Composition Variation of the 2023 May 16 Solar Energetic Particle Event Observed by SolO and PSP
Mitchell, D. G.; McComas, D. J.; Wimmer-Schweingruber, R. F. +13 more
In this study, we employ the combined charged particle measurements from Integrated Science Investigation of the Sun on board the Parker Solar Probe (PSP) and Energetic Particle Detector on board the Solar Orbiter (SolO) to study the composition variation of the solar energetic particle (SEP) event occurring on 2023 May 16. During the event, SolO …
Predicting Photospheric Ultraviolet Emission from Stellar Evolutionary Models
Liu, Jifeng; Wang, Song; Li, Xue +1 more
Stellar ultraviolet (UV) emission serves as a crucial indicator for estimating magnetic activity and evaluating the habitability of exoplanets orbiting stars. In this paper, we present a straightforward method to derive stellar photospheric UV emission for F to M main-sequence stars. By using PARSEC models, we establish relations between near-UV (…
Oblique Electrostatic Solitary and Supersolitary Waves in Earth's Magnetosheath
Singh, Kuldeep; Varghese, Steffy Sara; Saini, Nareshpal Singh +1 more
Nonlinear electrostatic solitary waves (ESWs) are routinely detected at various regions of Earth's magnetosphere using the Wideband Data plasma wave receivers mounted on board the Cluster satellite(s). This mission has facilitated the observation and analysis of ESW characteristics, such as amplitude and temporal duration within the magnetosheath,…
A Rapidly Accreting Active Galactic Nucleus Hidden in a Dust-obscured Galaxy at z ∼ 0.8
Brandt, William N.; Yu, Zhibo; Zou, Fan +3 more
Dust-obscured galaxies (DOGs) containing central supermassive black holes (SMBHs) that are rapidly accreting (i.e., having high Eddington ratios, λ Edd) may represent a key phase closest to the peak of both the black hole and galaxy growth in the coevolution framework for SMBHs and galaxies. In this work, we present a 68 ks XMM-Newton o…
Distance Estimate Method for Asymptotic Giant Branch Stars Using Infrared Spectral Energy Distributions
Stroh, Michael C.; Sahai, Raghvendra; Sjouwerman, Loránt O. +8 more
We present a method to estimate distances to asymptotic giant branch (AGB) stars in the Galaxy, using spectral energy distributions (SEDs) in the near- and mid-infrared. By assuming that a given set of source properties (initial mass, stellar temperature, composition, and evolutionary stage) will provide a typical SED shape and brightness, sources…
The Dependence of Joy's Law and Mean Tilt as a Function of Flux Emergence Phase
Will, Lucy W.; Norton, Aimee A.; Hoeksema, Jon Todd
Data from the Michelson Doppler Imager (MDI) and Helioseismic and Magnetic Imager (HMI) are analyzed from 1996 to 2023 to investigate tilt angles (γ) of bipolar magnetic regions and Joy's law for Solar Cycles 23 and 24 and a portion of Cycle 25. The HMI radial magnetic field (B r ) and MDI magnetogram (B los) data are used t…
Using the Cartwheel CME to Predict Off-limb Observations of CMEs for New and Upcoming UV and EUV Spectrometers
Landi, E.; Manchester, W. B.; Wraback, E. M.
Coronal mass ejections (CMEs) expel multithermal, magnetized plasma from the Sun, and when directed toward Earth, can cause extensive damage to space and ground-based electronics. To better understand the triggering, acceleration, and evolution of CMEs, it is critical to study CME plasma properties close to the Sun. High-resolution ultraviolet and…
How Does the Critical Torus Instability Height Vary with the Solar Cycle?
van Driel-Gesztelyi, Lidia; Green, Lucie M.; Barnes, Graham +2 more
The ideal magnetohydrodynamic torus instability can drive the eruption of coronal mass ejections. The critical threshold of magnetic field strength decay for the onset of the torus instability occurs at different heights in different solar active regions, and understanding this variation could therefore improve space weather prediction. In this wo…