In recent years, significant improvements in the sensitivity and image resolution of gamma-ray sky surveys provided by the current generation of ground-based particle detection arrays has led to groundbreaking discoveries. Among these discoveries are the detection of an unprecedented number of PeVatron candidates, multi-TeV gamma-ray emission associated with particle acceleration in the jets...
The imaging atmospheric cherenkov technique was first established with the detection of gamma--ray emission from the Crab nebula by the Whipple collaboration in 1989. Since then, the technique has continued to advance dramatically, with the use of stereoscopic observations, fast imaging cameras and machine learning analysis techniques, rapidly transitioning from studies of individual gamma-ray...
Large solar eruptive events, e.g. flares and coronal mass ejections, are capable of accelerating solar energetic particles (SEPs) to energies >300 MeV. These high energy SEP events are capable of causing disruption on Earth through ground level enhancements (GLEs). As such, the propagation of these particles towards Earth pose a significant space weather hazard. We explore past SEP events,...
In the last two decades, several techniques have been developed to predict the occurrence of Solar Proton Events (SPEs), which are mainly based on the statistical association between the >10 MeV proton flux and precursor parameters. In this framework, the Empirical model for Solar Proton Event Real Time Alert (ESPERTA) provides a prediction of SPEs after the occurrence of ≥M2 solar...
Systematic study of relativistic solar energetic particles provides key information about various processes, such as production and acceleration of energetic particles at the Sun and the interplanetary medium, interactions of energetic particles with magnetic fields in the heliosphere i.e. probing the electromagnetic and plasma conditions of the heliosphere, assessment of their terrestrial and...
In this talk we discuss recent observations and modelling endeavours of low-energy cosmic rays near Earth and in the inner heliosphere. We especially focus on observations that present a challenge to theoretical and numerical modelling studies. Topics include the record-setting galactic cosmic ray (GCR) levels observed during recent solar minima that were not accompanied by such high levels of...
We present high statistics measurements of 15 cosmic ray nuclei, H to Si and Fe, based on 10 years of the AMS data.
The China Seismo-Electromagnetic Satellite (CSES-01) is a sophisticated space observatory to monitor the ionosphere and study its coupling with the magnetosphere and the lithosphere. Launched in February 2018, in the framework of a joint cooperation program between the Chinese and Italian Space Agencies, it includes payloads to measure the electric and the magnetic field, plasma, X rays and...
The measurement of the energy spectrum of cosmic rays is of crucial importance to reveal their origin, propagation, and acceleration mechanisms. The Pierre Auger Observatory in Argentina and the Telescope Array (TA) in the US continue to observe cosmic rays by a hybrid detector, which is composed of Fluorescence Detectors (FD) and Surface Detector (SD) array, in the southern and northern...
The toe of the spectrum of ultra-high energy cosmic rays (UHECRs), above ~50 EeV, is an extremely interesting region for studying the origins of CRs. The potentially small magnetic deflections at these energies are coupled with the presence of the flux suppression, which could be a signature of the maximum acceleration potential of the sources, or could find its explanation in the interactions...
The origins of the high-energy cosmic neutrino flux remain largely unknown. Last year, a high-energy neutrino was associated with the tidal disruption event (TDE) AT2019dsg by our group. I will present AT2019fdr, an exceptionally luminous TDE candidate, coincident with another high-energy neutrino detected by IceCube. I will present observations that further support a TDE origin of this flare....
While the Antares undersea neutrino telescope has been decommissioned this year - after 15 years of continuous data taking - the KM3NeT neutrino telescopes are well underway in their construction in the same, deep, Mediterranean waters. The main scientific goals of the KM3NeT detectors are finding and studying sources of high-energy (TeV-PeV) neutrinos with KM3NeT/ARCA (Astroparticle Research...
The field of neutrino telescopes is continuously growing and better and more experimental data is becoming available. Besides the continuing interest in neutrino astronomy, these detectors can also be used for particle physics. In particular are neutrino telescopes complementary to lab based experiments, such as accelerators, offering different energy ranges and coming with different sources...
I will discuss various ways in which we can try to probe axion physics using the magnetospheres of neutron stars. I will focus in particular on two distinct possibilities: (i) the identification of radio lines coming from the resonant conversion of axion dark matter, and (ii) the possibility of sourcing axions directly from the plasma dynamics in the polar caps of neutron stars. I will show...
The last years have been dense with new developments in the search for the sources of Galactic cosmic rays (CRs): 1) The detection of features in the spectra of some primary chemicals opened new questions on the propagation of CRs in the Galaxy. 2) Precise measurements by AMS-02 of secondary nuclei are providing unique information about the transport processes over a larger energy domain 3)...
The newly launched eRosita X-ray satellite revealed two gigantic bubbles above and below the Galactic center. The "eRosita bubbles" bare a remarkable resemblance to the Fermi bubbles detected in gamma rays, suggesting a common origin. The physical origin of these giant Galactic bubbles has been hotly debated. Using 3D magnetohydrodynamic simulations including relevant cosmic-ray physics, we...
In 2012, during the centennial year of the discovery of cosmic rays, Voyager 1 crossed the heliopause and began making the very first in-situ observations of the surrounding interstellar medium. Joined by Voyager 2 in 2018, these twin spacecraft continue to provide critical measurements of cosmic rays in a surprising, previously-unexplored plasma regime from distinct vantage points. This talk...
