Speaker
Description
First Name: Gabriel
Last Name: Martín-Villacañas
Affiliation: Universidad de Alcalá, Space Research Group, Spain
All Authors: Raúl Gómez-Herrero, Francisco Espinosa Lara, Ignacio Cernuda, Juan José Blanco, Fernando Carcaboso, Laura Rodríguez-García, Javier Rodríguez-Pacheco, Patrick Kühl, Bernd Heber, Robert F. Wimmer-Schweingruber, George Ho.
Abstract: Forbush Decreases (FDs) are transient depressions in galactic cosmic-ray fluxes produced by the passage of interplanetary structures such as Interplanetary Coronal Mass Ejections (ICMEs) and Stream Interaction Regions (SIRs). The High Energy Telescope (HET), part of the Energetic Particle Detector (EPD) onboard Solar Orbiter provides single-detector count rates that enable continuous monitoring of galactic cosmic rays with good statistical accuracy, mainly sampling protons with energies above 10MeV, offering an excellent opportunity to investigate FDs at varying heliocentric distances. We present a catalog of FDs observed by Solar Orbiter from the start of its cruise phase (May 2020) through mid-2024. Events were identified using an automatic detection method based primarily on the count rates of the HET Bismuth Germanate (BGO) crystal scintillator. A preliminary analysis of the radial variation of FD amplitudes is also discussed. In addition, we highlight a selection of orbital configurations that are particularly favorable for future multipoint studies. Finally, we compare HET observations with ground-based neutron monitor data for the FDs of November 2021 and November 2023, when Solar Orbiter was near the Earth. These intervals provide a baseline for future comparisons at different heliocentric distances.