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The High-Resolution Coronal Imager, Flight 2.1
Tiwari, Sanjiv K.; Golub, Leon; Winebarger, Amy R. +49 more
The third flight of the High-Resolution Coronal Imager (Hi-C 2.1) occurred on May 29, 2018; the Sounding Rocket was launched from White Sands Missile Range in New Mexico. The instrument has been modified from its original configuration (Hi-C 1) to observe the solar corona in a passband that peaks near 172 Å, and uses a new, custom-built low-noise …
CME-HSS Interaction and Characteristics Tracked from Sun to Earth
Veronig, Astrid M.; Dumbović, Mateja; Temmer, Manuela +9 more
In a thorough study, we investigate the origin of a remarkable plasma and magnetic field configuration observed in situ on June 22, 2011, near L1, which appears to be a magnetic ejecta (ME) and a shock signature engulfed by a solar wind high-speed stream (HSS). We identify the signatures as an Earth-directed coronal mass ejection (CME), associated…
What the Sudden Death of Solar Cycles Can Tell Us About the Nature of the Solar Interior
Rempel, Matthias; McIntosh, Scott W.; Leamon, Robert J. +3 more
We observe the abrupt end of solar-activity cycles at the Sun's Equator by combining almost 140 years of observations from ground and space. These "terminator" events appear to be very closely related to the onset of magnetic activity belonging to the next solar cycle at mid-latitudes and the polar-reversal process at high latitudes. Using multi-s…
Fast Solar Image Classification Using Deep Learning and Its Importance for Automation in Solar Physics
Fletcher, Lyndsay; Armstrong, John A.
The volume of data being collected in solar physics has exponentially increased over the past decade and with the introduction of the Daniel K. Inouye Solar Telescope (DKIST) we will be entering the age of petabyte solar data. Automated feature detection will be an invaluable tool for post-processing of solar images to create catalogues of data re…
Unexpected Behavior of the Solar Wind Mass Flux During Solar Maxima: Two Peaks at Middle Heliolatitudes
Quémerais, Eric; Koutroumpa, Dimitra; Katushkina, Olga +2 more
In this work we study the temporal and latitudinal variations of the solar wind mass flux at 1 AU derived from SOHO/SWAN data on backscattered solar Lyman-α radiation in 1996 - 2018. Previously Katushkina et al. (J. Geophys. Res.118, 2800, 2013) have shown that the latitudinal profiles of the solar wind mass flux during the solar maximum 2001 - 20…
Which Photospheric Characteristics Are Most Relevant to Active-Region Coronal Mass Ejections?
Guerra, Jordan A.; Park, Sung-Hong; Bloomfield, D. Shaun +2 more
We investigate the relation between characteristics of coronal mass ejections and parameterizations of the eruptive capability of solar active regions widely used in solar flare-prediction schemes. These parameters, some of which are explored for the first time, are properties related to topological features, namely, magnetic polarity-inversion li…
CMEs in the Heliosphere: II. A Statistical Analysis of the Kinematic Properties Derived from Single-Spacecraft Geometrical Modelling Techniques Applied to CMEs Detected in the Heliosphere from 2007 to 2017 by STEREO/HI-1
Rodriguez, L.; Möstl, C.; Kilpua, E. K. J. +10 more
Recent observations with the Heliospheric Imagers (HIs) onboard the twin NASA Solar Terrestrial Relations Observatory (STEREO) spacecraft have provided unprecedented observations of a large number of coronal mass ejections (CMEs) in the inner heliosphere. In this article we discuss the generation of the HIGeoCAT CME catalogue and perform a statist…
Are Solar Energetic Particle Events and Type II Bursts Associated with Fast and Narrow Coronal Mass Ejections?
Gopalswamy, N.; Kahler, S. W.; Ling, A. G.
Gradual solar energetic (E >10 MeV) particle (SEP) events and metric through kilometric wavelength type II radio bursts are usually associated with shocks driven by fast (V ≥900 kms−1) and wide (W ≥60∘) coronal mass ejections (FW CMEs). This criterion was established empirically by several studies from solar cycle 23. The …
Interplanetary Coronal Mass Ejections During Solar Cycles 23 and 24: Sun-Earth Propagation Characteristics and Consequences at the Near-Earth Region
Joshi, Bhuwan; Cho, K. -S.; Moon, Y. -J. +2 more
In this article, we present a statistical study probing the relation between interplanetary coronal mass ejections (ICMEs) observed at 1 AU and their corresponding coronal mass ejections at the near-Sun region. The work encompasses the ICME activity that occurred during Solar Cycles 23 and 24 (1996 - 2017) while presenting an overall picture of IC…
A Catalogue of Forbush Decreases Recorded on the Surface of Mars from 2012 Until 2016: Comparison with Terrestrial FDs
Wimmer-Schweingruber, R. F.; Heber, B.; Herbst, K. +9 more
Forbush decreases (FDs) in galactic cosmic rays (GCRs) have been recorded by neutron monitors (NMs) at Earth for more than 60 years. For the past five years, with the establishment of the Radiation Assessment Detector (RAD) onboard the Mars Science Laboratory (MSL) rover Curiosity at Mars, it is possible to continuously detect, for the first time,…