Evolution of coronal mass ejections and the corresponding Forbush decreases: modelling vs multi-spacecraft observations
Mateja Dumbović, Bojan Vršnak, Jingnan Guo, Bernd Heber, Karin Dissauer, Fernando Carcaboso, Manuela Temmer, Astrid Veronig, Tatiana Podladchikova, Christian Mö… 展开作者
Mateja Dumbović, Bojan Vršnak, Jingnan Guo, Bernd Heber, Karin Dissauer, Fernando Carcaboso, Manuela Temmer, Astrid Veronig, Tatiana Podladchikova, Christian Möstl, Tanja Amerstorfer, Anamarija Kirin
One of the very common in situ signatures of interplanetary coronal mass ejections (ICMEs), as well as other interplanetary transients, are Forbush decreases (FDs), i.e. short-term reductions in the galactic cosmic ray (GCR) flux. A two-step FD is often regarded as a textbook example, which presumably owes its specific morphology to the fact that the measuring instrument passed through the ICME head-on, encountering first the shock front (if developed), then the sheath and finally the CME magnetic structure. The interaction of GCRs and the shock/sheath region, as well as the CME magnetic structure, occurs all the way from Sun to Earth, therefore, FDs are expected to reflect the evolutionary properties of CMEs and their sheaths. We apply modelling to different ICME regions in order to obtain a generic two-step FD profile, which qualitatively agrees with our current observation-based understanding of FDs. We next adapt the models for energy dependence to enable comparison with different GCR measurement instruments (as they measure in different particle energy ranges). We test these modelling efforts against a set of multi-spacecraft observations of the same event, using the Forbush decrease model for the expanding flux rope (ForbMod). We find a reasonable agreement of the ForbMod model for the GCR depression in the CME magnetic structure with multi-spacecraft measurements, indicating that modelled FDs reflect well the CME evolution.
Cosmic ray Forbush decreases (FDs) are usually thought to be due to Earth-directed coronal mass ejections (CMEs) from the Sun and their associated shocks. When CMEs and their shocks reach the Earth, they cause magnetic field compressions. We seek to understand the relation between these magnetic field compressions and FDs at rigidities between 12 and 42 GV using data from the GRAPES-3 instrument at Ooty. We find that the shapes of the Forbush decrease profiles show a startling similarity to that of the magnetic field compression in the near-Earth IP medium. We seek to understand the implicatio…
We employ remote observations of coronal mass ejections (CMEs) and the associated solar flares to forecast the CME-related Forbush decreases, i.e., short-term depressions in the galactic cosmic-ray flux. The relationship between the Forbush effect at the Earth and remote observations of CMEs and associated solar flares is studied via a statistical analysis. Relationships between Forbush decrease magnitude and several CME/flare parameters was found, namely the initial CME speed, apparent width, source position, associated solar-flare class and the effect of successive-CME occurrence. Based on t…
Interplanetary Coronal Mass Ejections (ICMEs) are known to modify the structure of the solar wind as well as interact with the space environment of planetary systems. Their large magnetic structures have been shown to interact with galactic cosmic rays, leading to the Forbush decrease (FD) phenomenon. We revisit in the present article the 17 years of Advanced Composition Explorer spacecraft ICME detection along with two neutron monitors (McMurdo and Oulu) with a superposed epoch analysis to further analyze the role of the magnetic ejecta in driving FDs. We investigate in the following the role…
We present an analytical diffusion-expansion Forbush decrease (FD) model ForbMod which is based on the widely used approach of the initially empty, closed magnetic structure (i.e. flux rope) which fills up slowly with particles by perpendicular diffusion. The model is restricted to explain only the depression caused by the magnetic structure of the interplanetary coronal mass ejection (ICME). We use remote CME observations and a 3D reconstruction method (the Graduated Cylindrical Shell method) to constrain initial boundary conditions of the FD model and take into account CME evolutionary prope…
Aims. We present observations of the first coronal mass ejection (CME) observed at the Solar Orbiter spacecraft on April 19, 2020, and the associated Forbush decrease (FD) measured by its High Energy Telescope (HET). This CME is a multispacecraft event also seen near Earth the next day. Methods. We highlight the capabilities of HET for observing small short-term variations of the galactic cosmic ray count rate using its single detector counters. The analytical ForbMod model is applied to the FD measurements to reproduce the Forbush decrease at both locations. Input parameters for the model are…
Accurate detection and precise timing of transient events such as X-ray photons, γ-ray burst, coronal mass ejections (CMEs), ground level enhancements (GLEs) and Forbush decreases (FDs) frequently raise issues that remain on the cutting edge of research in astrophysics. In an attempt to automate FD event selection, a combination of Fast Fourier transform as well as FD detection algorithms implemented in the statistical computing software R was developed and recently used to calculate the magnitude and FD event timing. The R-FD code implemented in the present study includes several different ca…
Aims. Forbush decrease (FD) is a transient decrease followed by a gradual recovery in the observed galactic cosmic ray intensity. We seek to understand the relationship between the FDs and near-Earth interplanetary magnetic field (IMF) enhancements associated with solar coronal mass ejections (CMEs). Methods. We use muon data at cutoff rigidities ranging from 14 to 24 GV from the GRAPES-3 tracking muon telescope to identify FD events. We select those FD events that have a reasonably clean profile, and magnitude > 0.25%. We use IMF data from ACE/WIND spacecrafts. We look for correlations betwee…
The Radiation Assessment Detector (RAD), on board Mars Science Laboratory's (MSL) Curiosity rover, has been measuring ground level particle fluxes along with the radiation dose rate at the surface of Mars since August 2012. Similar to neutron monitors at Earth, RAD sees many Forbush decreases (FDs) in the galactic cosmic ray (GCR) induced surface fluxes and dose rates. These FDs are associated with coronal mass ejections (CMEs) and/or stream/corotating interaction regions (SIRs/CIRs). Orbiting above the Martian atmosphere, the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft has also …
Based on our tool for the early diagnostics of solar eruption geoeffectiveness (EDSEG tool; Chertok et al., 2013, 2015, 2017), we have analyzed space weather disturbances that occurred in early September 2017. Two flares, SOL2017-09-04T20:33 (M5.5) and SOL2017-09-06T12:02 (X9.3), accompanied by Earth-directed halo coronal mass ejections (CMEs) were found to be geoeffective. We extracted the associated EUV dimmings and arcades and calculated their total unsigned magnetic flux. This calculation allowed us to estimate the possible scales of the Forbush decreases (FDs) and geomagnetic storms (GMSs…
Recently, we developed the Correlation-Aided Reconstruction (CORAR) method to reconstruct solar wind inhomogeneous structures, or transients, using dual-view white-light images (Li et al. 2020; Li et al. 2018). This method is proved to be useful for studying the morphological and dynamical properties of transients like blobs and coronal mass ejection (CME), but the accuracy of reconstruction may be affected by the separation angle between the two spacecraft (Lyu et al. 2020). Based on the dual-view CME events from the Heliospheric Imager CME Join Catalogue (HIJoinCAT) in the HELCATS (Heliosphe…
Forbush decreases (FDs) are depletions in the galactic cosmic ray (GCR) count rate that last typically for about a week and can be caused by coronal mass ejections (CMEs) or corotating interacting regions (CIRs). Fast CMEs that drive shocks cause large FDs that often show a two-step decrease where the first step is attributed to the shock/sheath region, while the second step is attributed to the closed magnetic structure. Since the difference in size of shock and sheath region is significant, and since there are observed effects that can be related to shocks and not necessarily to the sheath r…
The Athens Neutron Monitor Data Processing (ANMODAP) Center recorded an unusual Forbush decrease with a sharp enhancement of cosmic ray intensity right after the main phase of the Forbush decrease on 16 July 2005, followed by a second decrease within less than 12 h. This exceptional event is neither a ground level enhancement nor a geomagnetic effect in cosmic rays. It rather appears as the effect of a special structure of interplanetary disturbances originating from a group of coronal mass ejections (CMEs) in the 13-14 July 2005 period. The initiation of the CMEs was accompanied by type IV ra…
The Forbush decrease (FD) and Geomagnetic storm (GS) are the two distinct space weather events having common causing agents like interplanetary coronal mass ejection (ICME) or corotating interacting region (CIR). Generally, an ICME causes high amplitude FDs and extreme GSs. However, the interlinks between extreme GS and strong FDs are poorly studied. Here, we demonstrate five ICME induced extreme storms and their effects on respective FD profiles. We observed the sudden storm commencement of the GS coincides with the FD onset. Interestingly, we also noted a gradual increase in neutron counts d…
This study aims at the early diagnostics of geoeffectiveness of coronal mass ejections (CMEs) from quantitative parameters of the accompanying EUV dimming and arcade events. We study events of the 23th solar cycle, in which major non-recurrent geomagnetic storms (GMS) with Dst <-100 nT are sufficiently reliably identified with their solar sources in the central part of the disk. Using the SOHO/EIT 195 A images and MDI magnetograms, we select significant dimming and arcade areas and calculate summarized unsigned magnetic fluxes in these regions at the photospheric level. The high relevance of t…
On scales of days, the galactic cosmic ray (GCR) flux is affected by coronal mass ejections and corotating interaction regions (CIRs), causing so-called Forbush decreases and recurrent Forbush decreases (RFDs), respectively. We explain the properties and behavior of RFDs recorded at about 1 au that are caused by CIRs generated by solar wind high-speed streams (HSSs) that emanate from coronal holes. We employed a convection-diffusion GCR propagation model based on the Fokker-Planck equation and applied it to solar wind and interplanetary magnetic field properties at 1 au. Our analysis shows tha…
We compare estimates of the speed and width of coronal mass ejections (CMEs) in several catalogs for the CMEs associated with ~200 solar energetic particle (SEP) events in 2006-2013 that included 25 MeV protons. The catalogs used are: CDAW, CACTUS, SEEDS and CORIMP, all derived from observations by the LASCO coronagraphs on the SOHO spacecraft, the CACTUS catalog derived from the COR2 coronagraphs on the STEREO-A and -B spacecraft, and the DONKI catalog, which uses observations from SOHO and the STEREO spacecraft. We illustrate how, for this set of events, CME parameters can differ considerabl…
We analyze the precursor of a Forbush Decrease (FD) observed with the Global Muon Detector Network on December 14, 2006. An intense geomagnetic storm is also recorded during this FD with the peak Kp index of 8+. By using the "two-dimensional map" of the cosmic ray intensity produced after removing the contribution from the diurnal anisotropy, we succeed in extracting clear signatures of the precursor. A striking feature of this event is that a weak loss-cone signature is first recorded more than a day prior to the Storm Sudden Commencement (SSC) onset. This suggests that the loss-cone precurso…
We study 50 cosmic ray Forbush decreases (FDs) from the Oulu neutron monitor data during 1997-2005 that were associated with Earth-directed interplanetary coronal mass ejections (ICMEs). Such events are generally thought to arise due to the shielding of cosmic rays by a propagating diffusive barrier. The main processes at work are the diffusion of cosmic rays across the large-scale magnetic fields carried by the ICME and their advection by the solar wind. In an attempt to better understand the relative importance of these effects, we analyse the relationship between the FD profiles and those o…
The propagation of 15 interplanetary coronal mass ejections (ICMEs) from Earth's orbit (1 AU) to Mars (~ 1.5 AU) has been studied with their propagation speed estimated from both measurements and simulations. The enhancement of magnetic fields related to ICMEs and their shock fronts cause the so-called Forbush decrease, which can be de- tected as a reduction of galactic cosmic rays measured on-ground. We have used galactic cosmic ray (GCR) data from in-situ measurements at Earth, from both STEREO A and B as well as GCR measurements by the Radiation Assessment Detector (RAD) instrument onboard …
In-situ measurements carried out by spacecraft in radial alignment are critical to advance our knowledge on the evolutionary behavior of coronal mass ejections (CMEs) and their magnetic structures during propagation through interplanetary space. Yet, the scarcity of radially aligned CME crossings restricts investigations on the evolution of CME magnetic structures to a few case studies, preventing a comprehensive understanding of CME complexity changes during propagation. In this paper, we perform numerical simulations of CMEs interacting with different solar wind streams using the linear forc…
The large-scale magnetic structure of interplanetary coronal mass ejections (ICMEs) has been shown to cause decreases in the galactic cosmic ray (GCR) flux measured in situ by spacecraft, known as Forbush decreases (Fds). We use measurements of the GCR count rate obtained by MESSENGER during its orbital phase around Mercury to identify such Fds related to the passage of ICMEs and characterize their structure. Of the 42 ICMEs with corresponding high-quality GCR data, 79% are associated with a Fd. Thus a total of 33 ICME-related Fds were identified, 24 of which (73%) have a two-step structure. W…
We discuss how simultaneous observations by multiple heliospheric imagers can provide some important information about the azimuthal properties of Coronal Mass Ejections (CMEs) in the heliosphere. We propose two simple models of CME geometry that can be used to derive information about the azimuthal deflection and the azimuthal expansion of CMEs from SECCHI/HI observations. We apply these two models to four CMEs well-observed by both STEREO spacecraft during the year 2008. We find that in three cases, the joint STEREO-A and B observations are consistent with CMEs moving radially outward. In so…
Coronal mass ejections (CMEs) are a manifestation of the Sun's eruptive nature. They can have a great impact on Earth, but also on human activity in space and on the ground. Therefore, modelling their evolution as they propagate through interplanetary space is essential. EUropean Heliospheric FORecasting Information Asset (EUHFORIA) is a data-driven, physics-based model, tracing the evolution of CMEs through background solar wind conditions. It employs a spheromak flux rope, which provides it with the advantage of reconstructing the internal magnetic field configuration of CMEs. This is someth…
Many aspects of the three-dimensional (3-D) structure and evolution of interplanetary coronal mass ejections (ICMEs) remain unexplained. Here, we investigate two main topics: (1) the coherence scale of magnetic fields inside ICMEs, and (2) the dynamic nature of ICME magnetic complexity. We simulate ICMEs interacting with different solar winds using the linear force-free spheromak model incorporated into the EUHFORIA model. We place a swarm of ~20000 spacecraft in the 3-D simulation domain and characterize ICME magnetic complexity and coherence at each spacecraft based on simulated time series.…
The recent launch of Solar Orbiter and BepiColombo opened a brief window in which these two spacecraft were positioned in a constellation that allows for the detailed sampling of any Earth-directed CMEs. Fortunately, two such events occurred with in situ detections of an ICME by Solar Orbiter on the 19th of April and the 28th of May 2020. These two events were subsequently also observed in situ by BepiColombo and Wind around a day later. We attempt to reconstruct the observed in situ magnetic field measurements for all three spacecraft simultaneously using an empirical magnetic flux rope model…
We present a study of coronal mass ejections (CMEs) which impacted one of the STEREO spacecraft between January 2008 and early 2010. We focus our study on 20 CMEs which were observed remotely by the Heliospheric Imagers (HIs) onboard the other STEREO spacecraft up to large heliocentric distances. We compare the predictions of the Fixed-Phi and Harmonic Mean (HM) fitting methods, which only differ by the assumed geometry of the CME. It is possible to use these techniques to determine from remote-sensing observations the CME direction of propagation, arrival time and final speed which are compar…
Polarimetric Tomography Applied to Synthetic Multi-Spacecraft White-Light Images: Observing Coronal Mass Ejections in 3D
UKRI – RAL Space, Rutherford Appleton Laboratory（英国研究委员会 - 拉尔夫空间部，鲁瑟福阿普尔顿实验室）；Predictive Science Inc.（预测科学公司）；Austrian Space Weather Office, GeoSphere Austria（奥地利空间天气办公室，地球圈奥地利）；Department of Physics, University of Helsinki（赫尔辛基大学物理系）；Department of Meteorology, University of Reading（雷丁大学气象系）；Faculty of Geodesy, University of Zagreb（萨格勒布大学大地测量学院）；Institute of Physics, University of Graz（格拉茨大学物理研究所）；U.S. Naval Research Laboratory（美国海军研究实验室）；The Johns Hopkins University Applied Physics Laboratory（约翰斯·霍普金斯大学应用物理实验室）
In this work, non-recurrent Forbush decreases (FDs) triggered by the passage of shock-driven interplanetary coronal mass ejections (ICMEs) have been analyzed. Fifty-nine ICMEs have been studied but only the 25% of them were associated to a FD. We find that shock-driving magnetic clouds (MCs) produce deeper FDs than shock-driving ejecta. This fact can be explained regarding to the observed growing trends between decreases in neutron monitor (NM) count rate and MC/ejecta speed and its associated rigidity. MCs are faster and have higher associated rigidities than ejecta. Also the deceleration of …
The twin Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) COR2 coronagraphs of the Solar Terrestrial Relations Observatory (STEREO) provide images of the solar corona from two view points in the solar system. Since their launch in late 2006, the STEREO Ahead (A) and Behind (B) spacecrafts have been slowly separating from Earth at a rate of 22.5 degrees per year. By the end of 2007, the two spacecraft were separated by more than 40 degrees from each other. At this time, we began to see large-scale differences in the morphology and total intensity between coronal mass ejectio…
We present an algorithm to detect the outer edges of Coronal Mass Ejection (CME) events as seen in differences of Heliospheric Imager STEREO SECCHI HI-1 images from either A or B spacecraft, as well as its implementation in Python.
Using data from the Heliospheric Imagers (HIs) onboard STEREO, it is possible to derive the direction of propagation of coronal mass ejections (CMEs) in addition to their speed with a variety of methods. For CMEs observed by both STEREO spacecraft, it is possible to derive their direction using simultaneous observations from the twin spacecraft and also, using observations from only one spacecraft with fitting methods. This makes it possible to test and compare different analyses techniques. In this article, we propose a new fitting method based on observations from one spacecraft, which we co…
We seek to identify the primary agents causing Forbush decreases (FDs) observed at the Earth in high rigidity cosmic rays. In particular, we ask if such FDs are caused mainly by coronal mass ejections (CMEs) from the Sun that are directed towards the Earth, or by their associated shocks. We use the muon data at cutoff rigidities ranging from 14 to 24 GV from the GRAPES-3 tracking muon telescope to identify FD events. We select those FD events that have a reasonably clean profile, and can be reasonably well associated with an Earth-directed CME and its associated shock. We employ two models: on…
Galactic cosmic-ray (GCR) energy spectra observed in the inner heliosphere are modulated by the solar activity, the solar polarity and structures of solar and interplanetary origin. A high counting rate particle detector (PD) aboard LISA Pathfinder (LPF), meant for subsystems diagnostics, was devoted to the measurement of galactic cosmic-ray and solar energetic particle integral fluxes above 70 MeV n$^{-1}$ up to 6500 counts s$^{-1}$. PD data were gathered with a sampling time of 15 s. Characteristics and energy-dependence of GCR flux recurrent depressions and of a Forbush decrease dated Augus…
Owing to our dependance on spaceborne technology, an awareness of disturbances in the near-Earth space environment is proving to be increasingly crucial. Earth-directed Coronal mass ejections (CMEs) emanating from the Sun are the primary drivers of space weather disturbances. Studies of CMEs, their kinematics, and their near-Earth effects are therefore gaining in importance. The effect of CMEs near the Earth is often manifested as transient decreases in galactic cosmic ray intensity, which are called Forbush decreases (FDs). In this thesis we probe the structure of CMEs and their associated sh…
Stealth coronal mass ejections (CMEs) are eruptions from the Sun that have no obvious low coronal signature. These CMEs are characteristically slower events, but can still be geoeffective and affect space weather at Earth. Therefore, understanding the science underpinning these eruptions will greatly improve our ability to detect and, eventually, forecast them. We present a study of two stealth CMEs analysed using advanced image processing techniques that reveal their faint signatures in observations from the extreme ultraviolet (EUV) imagers onboard the Solar and Heliospheric Observatory (SOH…
Validating a Non-conventional Method for Expansion of Coronal Mass Ejections (CMEs) and Investigating the Evolution of a CME Substructures Using Solar Orbiter and Wind Observations
University of Reading（雷丁大学）；Austrian Space Weather Office, GeoSphere Austria（奥地利空间天气办公室，地球系统奥地利）；Indian Institute of Astrophysics（印度天体物理研究所）；Pondicherry University（本地治里大学）
The Fixed-Φ(FΦ) and Harmonic Mean (HM) fitting methods are two methods to determine the average direction and velocity of coronal mass ejections (CMEs) from time-elongation tracks produced by Heliospheric Imagers (HIs), such as the HIs onboard the STEREO spacecraft. Both methods assume a constant velocity in their descriptions of the time-elongation profiles of CMEs, which are used to fit the observed time-elongation data. Here, we analyze the effect of aerodynamic drag on CMEs propagating through interplanetary space, and how this drag affects the result of the FΦand HM fitting methods. A sim…
We analyse the 2010 April 3rd CME using spacecraft coronagraphic images at different vantage points (SOHO, STEREO-A and STEREO-B). We perform a 3D reconstruction of both the flux rope and shock using the Graduated Cylindrical Shell (GCS) model to calculate CME kinematic and morphologic parameters (e.g. velocity, acceleration, radius). The obtained results are fitted with empirical models describing the expansion of the CME radius in the heliosphere and compared with in situ measurements from Wind spacecraft: the CME is found to expand linearly towards Earth. Finally, we relate the event with d…
We present an analysis of {\it in situ} and remote-sensing measurements of a coronal mass ejection (CME) that erupted on 2021 February 20 and impacted both the Solar TErrestrial RElations Observatory (STEREO)-A and the {\it Wind} spacecraft, which were separated longitudinally by 55$^\circ$. Measurements on 2021 February 24 at both spacecraft are consistent with the passage of a magnetic ejecta (ME), making this one of the widest reported multi-spacecraft ME detections. The CME is associated with a low-inclined and wide filament eruption from the Sun's southern hemisphere, which propagates bet…
We have performed, for the first time, the successful automated detection of Coronal Mass Ejections (CMEs) in data from the inner heliospheric imager (HI-1) cameras on the STEREO A spacecraft. Detection of CMEs is done in time-height maps based on the application of the Hough transform, using a modified version of the CACTus software package, conventionally applied to coronagraph data. In this paper we describe the method of detection. We present the result of the application of the technique to a few CMEs that are well detected in the HI-1 imagery, and compare these results with those based o…
We analyze the detection capability of Coronal Mass Ejections (CMEs) for all currently operating coronagraphs in space. We define as CMEs events that propagate beyond 10 solar radii with morphologies broadly consistent with a magnetic flux rope presence. We take advantage of multi-viewpoint observations over five month-long intervals, corresponding to special orbital configurations of the coronagraphs aboard the STEREO and SOHO missions. This allows us to sort out CMEs from other outward-propagating features (e.g. waves or outflows), and thus to identify the total number of unique CMEs ejected…
Visualizing the Magnetic Structure in Interplanetary Coronal Mass Ejections with ATHARV
Indian Institute of Science (IISc)（印度科学研究所）；Aryabhatta Research Institute of Observational Sciences (ARIES)（阿里亚巴塔观测科学研究所）；Mahatma Jyotiba Phule Rohilkhand University（马哈特玛·乔蒂巴·普尔罗希尔坎德大学）；Indian Institute of Technology Delhi（德里印度理工学院）；Indian Institute of Space Science and Technology (IIST)（印度空间科学与技术学院）；IISER Kolkata（加尔各答印度科学教育研究所）
Context: Late on 2013 August 19, a coronal mass ejection (CME) erupted from an active region located near the far-side central meridian from Earth's perspective. The event and its accompanying shock were remotely observed by the STEREO-A, STEREO-B and SOHO spacecraft. The interplanetary counterpart (ICME) was intercepted by MESSENGER near 0.3 au, and by both STEREO-A and STEREO-B, near 1 au, which were separated by 78° in heliolongitude. The main objective of this study is to follow the radial and longitudinal evolution of the ICME throughout the inner heliosphere, and to examine possible scen…
We investigate the coronal and interplanetary evolution of a coronal mass ejection (CME) launched on 2010 September 4 from a source region linking two active regions (ARs) 11101 and 11103, using extreme ultraviolet imaging, magnetogram, white-light and in situ observations from SDO, STEREO, SOHO, VEX and Wind. A potential-field source-surface model is employed to examine the configuration of the coronal magnetic field surrounding the source region. The graduated cylindrical shell model and a triangulation method are applied to determine the kinematics of the CME in the corona and interplanetar…
On the Role of Alfvenic Fluctuations as Mediators of Coherence within Interplanetary Coronal Mass Ejections: Investigation of Multi-Spacecraft Measurements at 1 au
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 Matter Exploration and Light-nuclei Astrophysics (PAMELA) satellite experiment. The analyzed data sample includes 32 SEP events occurring between 2010 and 2014, with a statistically significant proton signal at energies in excess of a few tens of MeV, …
Decades of studies have suggested several criteria to detect Interplanetary coronal mass ejections (ICME) in time series from in-situ spacecraft measurements. Among them the most common are an enhanced and smoothly rotating magnetic field, a low proton temperature and a low plasma beta. However, these features are not all observed for each ICME due to their strong variability. Visual detection is time-consuming and biased by the observer interpretation leading to non exhaustive, subjective and thus hardly reproducible catalogs. Using convolutional neural networks on sliding windows and peak de…
