Results 31 to 40 of about 3,043 (224)

The Impact of Multifluid Effects in the Solar Chromosphere on the Ponderomotive Force under SE and NEQ Ionization Conditions

The Astrophysical Journal, 2023
The ponderomotive force has been suggested to be the main mechanism to produce the so-called first ionization potential (FIP) effect—the enrichment of low-FIP elements observed in the outer solar atmosphere, in the solar wind, and in solar energetic ...
Juan Martínez-Sykora, Bart De Pontieu, Viggo H. Hansteen, Paola Testa, Q. M. Wargnier, Mikolaj Szydlarski   +5 more
doaj   +1 more source

Element Abundances in Impulsive Solar Energetic Particle Events

The Astrophysical Journal, 2023
We outline and discuss a model for the enhanced abundances of trans-Fe elements in impulsive solar energetic particle (SEP) events, where large mass-dependent abundance enhancements are frequently seen.
J. Martin Laming, Natsuha Kuroda
doaj   +1 more source

Observational signatures of waves and flows in the solar corona [PDF]

, 2015
DM acknowledges support of a Royal Society University Research Fellowship and a KU Leuven Research Council senior research fellowship (SF/12/008). The research leading to these results has also received funding from the European Commission Seventh ...
Antolin, Patrick, Van Doorsselaere, T., De Moortel, I., Van Doorsselaere, Tom   +3 more
core   +1 more source

Spectral Irradiance Observations and Projections for Solar Cycle 25

Earth and Space Science, Volume 13, Issue 4, April 2026.
Abstract The Ozone Monitoring Instrument (OMI) on the Aura satellite makes near‐daily measurements of solar spectral irradiance (SSI) at wavelengths between 265 and 500 nm for instrument calibration purposes. The low degradation and exceptional stability of OMI's calibration during its lifetime facilitates the creation of a new 18‐year OMI Version 7 ...
Matthew T. DeLand, Sergey V. Marchenko, Judith L. Lean, Odele Coddington   +3 more
wiley   +1 more source

Investigating Alfvénic wave propagation in coronal open-field regions

, 2015
The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves.
Morton, Richard, Tomczyk, Steve, Pinto, Rui   +2 more
core   +1 more source

Parker Solar Probe Observations of Proton Core‐Beam Distributions in Heliospheric Current Sheet Region: Quasilinear Instability Analysis Combined With Collisional Relaxation

Journal of Geophysical Research: Space Physics, Volume 131, Issue 4, April 2026.
Abstract Parker Solar Probe has been proven as instrumental for the observation of young solar wind. During the encounters E‐07 and E‐08, PSP recorded the core plus beaming protons crossing the heliospheric current Sheet region. When the observed PSP data is plotted in the temperature ratio versus parallel beta space, it is found that the occurrence ...
M. Rashid, P. H. Yoon, J. Huang, C. Salem, M. Sarfraz, S. Alnussirat, R. A. López, J. Seough, H. Xie, D. Larson, R. Livi   +10 more
wiley   +1 more source

The influence of the magnetic field on running penumbral waves in the solar chromosphere

, 2013
We use images of high spatial and temporal resolution, obtained using both ground- and space-based instrumentation, to investigate the role magnetic field inclination angles play in the propagation characteristics of running penumbral waves in the solar ...
Jess, D.B.; id_orcid, Van Doorsselaere, T., Reznikova, V, Keys, P. H.; id_orcid, Mackay, D.H., Reznikova, Veronika, Mackay, Duncan Hendry, Keys, P.H., Jess, David, Keys, Peter, Reznikova, V. E., Van Doorsselaere, Tom, MacKay, D. H.   +12 more
core   +1 more source

Detection of a Magnetic Discontinuity in the Upper Solar Chromosphere Associated with a Coronal Loop Brightening Observed by CLASP2.1

The Astrophysical Journal
We report the first detection of a magnetic discontinuity in the upper solar chromosphere associated with a coronal loop brightening. Our findings are based on novel observations obtained by the Chromospheric LAyer SpectroPolarimeter (CLASP2.1 ...
Donguk Song, Ryohko Ishikawa, David E. McKenzie, Javier Trujillo Bueno, Frédéric Auchère, Ryouhei Kano, Amy Winebarger, Takenori J. Okamoto, Laurel A. Rachmeler, Ken Kobayashi, Genevieve D. Vigil, Adam R. Kobelski, Christian Bethge, Eun-Kyung Lim, Luca Belluzzi, Ernest Alsina Ballester, Tanausú del Pino Alemán, Jiří Štěpán   +17 more
doaj   +1 more source

Reconstructing Historical Solar Indices for Predicting Past Space Weather Events

Space Weather, Volume 24, Issue 4, April 2026.
Abstract Modeling and forecasting the near‐Earth space environment, specifically the thermosphere, is particularly important because it affects the motion of low‐Earth orbit objects through atmospheric drag. Solar indices such as F10.7, S10.7, M10.7, and Y10.7 are commonly used as inputs to ionospheric and thermospheric density models.
Poshan Belbase, Denny M. Oliveira, Theodosios Chatzistergos, Gangkai Poh, Eftyhia Zesta   +4 more
wiley   +1 more source

How Are the Abnormally Hot Chromosphere and Corona Heated by the Solar Magnetic Fields?

The Astrophysical Journal
The corona is a structure possessed by stars, including the Sun. The abnormal heating of the solar corona and chromosphere is one of the greatest mysteries in modern astronomy.
K. J. Li, J. C. Xu, W. Feng, J. L. Xie, X. J. Shi, L. H. Deng   +5 more
doaj   +1 more source