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CME-Driven and Flare-Ignited Fast Magnetosonic Waves Detected in a Solar Eruption
Shen, Yuandeng; Zhou, Chengrui; Zhou, Xinping +4 more
We present Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) observation of three types of fast-mode, propagating, magnetosonic waves in a GOES C3.0 flare on 23 April 2013, which was accompanied by a prominence eruption and a broad coronal mass ejection (CME). During the fast-rising phase of the prominence, a large-scale, dome-shap…
Science Highlights and Final Updates from 17 Years of Total Solar Irradiance Measurements from the SOlar Radiation and Climate Experiment/Total Irradiance Monitor (SORCE/TIM)
Kopp, Greg
The final version (V.19) of the total solar irradiance data from the SOlar Radiation and Climate Experiment (SORCE) Total Irradiance Monitor has been released. This version includes all calibrations updated to the end of the mission and provides irradiance data from 25 February 2003 through 25 February 2020. These final calibrations are presented …
Empirical Model of 10 - 130 MeV Solar Energetic Particle Spectra at 1 AU Based on Coronal Mass Ejection Speed and Direction
Richardson, Ian G.; Bruno, Alessandro
We present a new empirical model to predict solar energetic particle (SEP) event-integrated and peak intensity spectra between 10 and 130 MeV at 1 AU, based on multi-point spacecraft measurements from the Solar TErrestrial RElations Observatory (STEREO), the Geostationary Operational Environmental Satellites (GOES), and the Payload for Antimatter …
Propagating Conditions and the Time of ICME Arrival: A Comparison of the Effective Acceleration Model with ENLIL and DBEM Models
Vourlidas, Angelos; Dumbović, Mateja; Papaioannou, Athanasios +5 more
The Effective Acceleration Model (EAM) predicts the Time-of-Arrival (ToA) of the Coronal Mass Ejection (CME) driven shock and the average speed within the sheath at 1 AU. The model is based on the assumption that the ambient solar wind interacts with the interplanetary CME (ICME) resulting in constant acceleration or deceleration. The upgraded ver…
Transiting Exoplanet Survey Satellite (TESS) Observations of Flares and Quasi-Periodic Pulsations from Low-Mass Stars and Potential Impact on Exoplanets
Ramsay, Gavin; Doyle, Lauren; Doyle, J. Gerry +1 more
We have performed a search for flares and quasi-periodic pulsations (QPPs) from low-mass M-dwarf stars using Transient Exoplanet Survey Satellite (TESS) two-minute cadence data. We find seven stars that show evidence of QPPs. Using Fourier and empirical mode decomposition techniques, we confirm the presence of 11 QPPs in these seven stars with a p…
Deciphering Solar Magnetic Activity: 140 Years of the `Extended Solar Cycle' - Mapping the Hale Cycle
Velli, Marco; McIntosh, Scott W.; Srivastava, Abhishek K. +6 more
We investigate the occurrence of the "extended solar cycle" (ESC) as it occurs in a host of observational data spanning 140 years. Investigating coronal, chromospheric, photospheric, and interior diagnostics, we develop a consistent picture of solar activity migration linked to the 22-year Hale (magnetic) cycle using superposed epoch analysis (SEA…
Solar Wind Helium Abundance Heralds Solar Cycle Onset
McIntosh, Scott W.; Kasper, Justin C.; Leamon, Robert J. +1 more
We study the solar wind helium-to-hydrogen abundance's (AHe) relationship to solar cycle onset. Using OMNI/Lo data, we show that AHe increases prior to sunspot number (SSN) minima. We also identify a rapid depletion and recovery in AHe that occurs directly prior to cycle onset. This AHe shutoff happens a…
Overview of the Solar Radiation and Climate Experiment (SORCE) Seventeen-Year Mission
Woods, Thomas N.; Kopp, Greg; Harder, Jerald W. +4 more
The Solar Radiation and Climate Experiment (SORCE) was a NASA mission that operated from 2003 to 2020 to provide key climate-monitoring measurements of total solar irradiance (TSI) and solar spectral irradiance (SSI). Three important accomplishments of the SORCE mission are i) the continuation of the 42-year-long TSI climate data record, ii) the c…
Active Region Contributions to the Solar Wind over Multiple Solar Cycles
van Driel-Gesztelyi, Lidia; Green, Lucie M.; Horbury, Timothy S. +1 more
Both coronal holes and active regions are source regions of the solar wind. The distribution of these coronal structures across both space and time is well known, but it is unclear how much each source contributes to the solar wind. In this study we use photospheric magnetic field maps observed over the past four solar cycles to estimate what frac…
Simulating the Coronal Evolution of Bipolar Active Regions to Investigate the Formation of Flux Ropes
Green, L. M.; Yardley, S. L.; Mackay, D. H.
The coronal magnetic field evolution of 20 bipolar active regions (ARs) is simulated from their emergence to decay using the time-dependent nonlinear force-free field method of Mackay, Green, and van Ballegooijen (Astrophys. J. 729, 97, 2011). A time sequence of cleaned photospheric line-of-sight magnetograms, which covers the entire evolution of …