Moderadores
Cosmic Rays
- Mercedes Paniccia (University of Geneva (CH))
Cosmic Rays
- Brian Rauch (Washington University in St. Louis)
Cosmic Rays
- Ioana Maris (Université Libre de Bruxelles)
Cosmic Rays
- Arjen van Vliet (DESY Zeuthen)
Cosmic Rays
- Denise Boncioli (University of L'Aquila and INFN-LNGS)
Cosmic Rays
- maurizio spurio (University of Bologna (Italy) and INFN)
The Alpha Magnetic Spectrometer (AMS) is a precision particle physics detector operating on the International Space Station. Since 2011, AMS has collected more than 250 billion charged cosmic rays with energies up to multi-TeV. The high-precision measurements with ~1% accuracy have led to many surprising observations. The latest results on cosmic elementary particles (electrons, positrons,...
The CALorimetric Electron Telescope (CALET) has been in operation on the International Space Station (ISS) since October 2015, providing nearly ten years of high-precision, continuous observations of cosmic rays. The CALET mission aims to search for signatures of nearby sources and dark matter through observations of high-energy cosmic-ray electrons, and to contribute to the study of...
The space-based DAMPE (DArk Matter Particle Explorer) detector has been taking data since its successful launch in December 2015. Its main scientific goals include the indirect search for dark matter signatures in the cosmic electron and gamma-ray spectra, the measurements of galactic cosmic ray fluxes from tens of GeV up to hundreds of TeV and high energy gamma ray astronomy above a few GeV....
Measurements of clock isotopes, particularly that of the Be-10/Be-9 ratio, can be used to provide unique information on galactic cosmic ray propagation. The High Energy Light Isotope eXperiment (HELIX) is a balloon-borne magnet spectrometer designed to measure cosmic ray isotopes with an event-by-event mass resolution of 3%. The experiment aims to improve the statistics and extend measurements...
The Trans-Iron Galactic Element Recorder (TIGER) family of instruments are designed to make the best single-element resolution measurements of the Ultra-Heavy Galactic Cosmic Rays (UHGCRs) to probe their origins and the sources of nucleosynthesis. The TIGER and SuperTIGER stratospheric long-duration balloon-borne detectors have each had two successful flights from Antarctica, with TIGER making...
Analysis of anisotropy of the arrival directions of galactic positrons, electrons and protons has been performed with the Alpha Magnetic Spectrometer on the International Space Station. This measurement allows to differentiate between point-like and diffuse sources of cosmic rays for the understanding of the origin of high energy positrons or the hardening in the proton flux. The AMS results...
We present results over an 11-year Solar cycle of cosmic antiprotons in the rigidity range from 1.00 to 41.9 GV. The antiproton fluxes exhibit distinct properties. Compared with other cosmic elementary particle fluxes (proton, electron, and positron), the magnitude of the antiproton flux temporal variation is significantly smaller. A hysteresis between the antiproton fluxes and the proton...
Phosphorus (P) nuclei in cosmic rays are secondary particles thought to be mainly produced by the collisions of heavier nuclei with the interstellar medium. The precise measurement of P nuclei is crucial for advancing the understanding of cosmic ray propagation. We present the latest results on the properties of P cosmic-ray nuclei flux in the rigidity range 2.15 GV to 1.2 TV based on 0.16...
We present high statistics measurements of the secondary cosmic rays Lithium, Beryllium, Boron, and Fluorine based on 11.5 years of AMS data. The properties of the secondary cosmic ray fluxes and their ratios to the primary cosmic rays Li/C, Be/C, B/C, Li/O, Be/O, B/O, and F/Si are discussed. The systematic comparison with the latest GALPROP cosmic ray model is presented.
Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of the deuteron ($D$) flux are presented. The measurements are based on 21 million $D$ nuclei in the rigidity range from 1.9 to 21 GV collected from May 2011 to April 2021. We observe that over the entire rigidity range the $D$ flux exhibits nearly identical time variations with the $p$, $^3$He ,...
Beryllium nuclei in cosmic rays are expected to be secondaries produced by the fragmentation of primary cosmic rays during their propagation in the Galaxy. Therefore, their fluxes contain essential information on cosmic ray propagation and sources. As the radioactive isotope 10Be decays to 10B with a half-life comparable to the cosmic-ray residence time in the Galaxy, the 10Be/9Be ratio can be...
Recent cosmic-ray (CR) measurements have revealed unexpected anomalies in secondary CRs, namely deviations from the predictions of the so-called standard Galactic CR paradigm regarding the composition and energy spectra of the products of interactions of primary (accelerated) CRs with interstellar gas: (i) antiparticles (positrons and antiprotons), (ii) light elements of the (Li, Be, B) group,...
The electron + positron cosmic-ray flux recently released by the H.E.S.S. telescope shows a remarkable behaviour: It breaks at around 1 TeV and falls off quickly, following a smooth powerlaw. This is in tension with simple pulsar models, which predict a much harder electron spectrum at tens of TeV. However, in two-zone diffusion models, propagation of high-energy electrons is inhibited in a...
The origin and nature of cosmic rays remain one of the most intriguing unsolved problems in modern astrophysics, even more than a century after their discovery.
The Telescope Array (TA) is the largest cosmic ray observatory in the northern hemisphere, continuously observing ultra-high energy cosmic rays (E$>10^{18}\,$eV) with a hybrid detector composed of fluorescence detectors (FD) and a...
Ground-based full-sky studies of the angular distribution of arrival directions of ultra-high-energy cosmic rays require combining data from different observatories, such as the Pierre Auger Observatory and the Telescope Array, because no single array can cover all declinations. A working group comprising members from both the Pierre Auger and Telescope Array collaborations has been tasked...
The origin of ultra-high-energy cosmic rays (UHECRs) remains one of the most compelling open questions in astroparticle physics. The Pierre Auger Observatory, the world’s largest facility for cosmic ray detection, has provided unprecedented data to investigate anisotropies in UHECR arrival directions. At large angular scales, a significant dipolar modulation in right ascension has been...
Ultra-high-energy cosmic rays (UHECRs) get deflected by extragalactic magnetic fields (EGMFs) when they propagate from their sources to Earth. The spread of UHECRs around their source position provides a measure of the strength of the turbulent EGMFs between the UHECR sources and Earth. Recent results from the Pierre Auger Observatory suggest correlations between the arrival directions of...
One of the major challenges in astrophysics is the estimation of the mass composition of ultra-high-energy cosmic rays (UHECRs), ions with energies exceeding $1\,\text{EeV}$ of extraterrestrial origin. Due to the low flux of UHECRs, the direct detection of the particles is infeasible, which poses several challenges for estimating their mass. When a UHECR enters Earth's atmosphere, it will...
CORSIKA 8 is a modern Monte-Carlo simulation framework for particle showers in air and dense media. It is designed as a modular and modern C++ framework, providing the flexibility that is needed for current and future astroparticle physics experiments. In addition to the standard hadronic interaction models for air showers, it also includes the next generation models EPOS-LHC-R and QGSJetIII...
Energy calibration in indirect air shower detection presents a challenging problem due to the impossibility of controlled laboratory validation. Traditionally, hybrid measurements combining fluorescence detectors (FD) and surface detectors (SD) have relied on calibrating the SD using FD data, assuming that fluorescence measurements closely reflect the calorimetric principle. However, SD energy...
Recent high-precision measurements of cosmic rays have revealed spectral features that are not justified by a simple power-law behavior. These deviations provide valuable insights into cosmic ray acceleration, propagation, and injection mechanisms, including possible contributions from nearby sources. Among the various cosmic ray species, protons—being the most abundant and least charged...
Iron nuclei are the most abundant heavy component of cosmic rays and provide critical insight into their astrophysical origin and propagation. Ground-based IACT telescopes have demonstrated the effectiveness of using the direct Cherenkov light emission of heavy atomic nuclei high-up in the atmosphere for measuring the iron spectrum in the multi-TeV energy range. Building on previous results...
We present preliminary results from a study of the anisotropy in cosmic-ray arrival directions as observed by IceTop, the surface array component of the IceCube Neutrino Observatory. IceTop is primarily sensitive to cosmic rays in the PeV energy range, providing complementary data to and extending beyond recently published results from IceCube’s in-ice component. This work uses 10 years of...
The Compton-Getting effect — an apparent dipolar anisotropy of cosmic rays generated by Earth's orbital motion around the Sun — serves as a known calibration source for cosmic-ray anisotropy studies. The amplitude of the Compton-Getting dipole depends on both the orbital speed and the mean spectral index of the cosmic-ray flux. It therefore provides an indirect method for studying the energy...
Muons, created by the interactions of cosmic rays with the Earth's atmosphere, form the main component of the cosmic ray air showers which reach underwater or in-ice detectors such as KM3NeT and IceCube. Precise measurements of such muons can provide key insights into the properties of cosmic rays, and their interactions. The KM3NeT research infrastructure consists of two telescopes in the...
The Pierre Auger Observatory, the largest air-shower detector in the world, provides unmatched exposure to photons with energies above 5 × 10¹⁶ eV. Its hybrid detection system - combining a surface detector array and fluorescence telescopes - enables the most stringent upper limits on the diffuse Ultra-High-Energy photon flux, achieved through advanced discrimination of photon-induced air...
The internal structure and dynamics of relativistic jets in active galactic nuclei (AGN) are central to understanding where and how particles are accelerated to very high energies. In particular, recollimation shocks and the turbulent regions they generate downstream can serve as natural sites for localized energy dissipation and non-thermal particle energization. Using high-resolution 2D and...
Recently, LHAASO has announced the highest-energy measurements of the diffusive gamma-ray flux, offering the possibility of probing the spatial distribution and energy spectrum of the galactic cosmic rays (CRs) up to the all-particle spectrum knee ( PeV). However, a persistent tension between observations by experiments (such as Fermi and LHAASO) and the predictions based on measurements of...
The cosmic ray knee, observed at around 4 PeV, marks a striking feature in the all-particle cosmic ray spectrum and is widely regarded as the signature of the end of the Galactic component. Recent direct measurements from DAMPE, CALET, and ISS-CREAM are now probing the spectrum with unprecedented precision up to the vicinity of the knee, while LHAASO has provided groundbreaking indirect data...
The transition from diffusion to gradient-curvature drift as the dominant mechanism for the Galactic escape of cosmic rays (CRs) is considered a possible origin of the CR “knee". We studied the connection between antisymmetric diffusion and these drifts by performing test-particle simulations of CR propagation in synthetic turbulent magnetic fields using the Monte Carlo code CRPropa 3. We...
Supernova remnants (SNRs) are often considered as the main sites of acceleration of Galactic cosmic rays, up to the knee feature in the cosmic-ray spectrum. However, their ability to accelerate particles to reach PeV energies is questionable and lacks observational evidence. Theoretical predictions suggest that only a small subclass of very young SNRs evolving in dense environments could...
The origin of Galactic cosmic rays (CRs), particularly around the knee region ($\sim$3 PeV), remains a major unsolved question. Recent observations by LHAAASO suggest that the knee is shaped mainly by protons, with a transition to heavier elements at higher energies.
Microquasars -- compact jet-emitting sources -- have emerged as possible PeV CR accelerators, especially after detections of...
The mysterious sources of high energy cosmic rays must be able to explain the power-law flux in energy as well as the nuclear composition changes at spectral breaks. Interacting supernovae may be able to explain these observed features. We build on a self-consistent model of the shock formed between supernova ejecta and the circumstellar medium by accounting for the composition of accelerated...
The study of UHE $\gamma$-ray emission plays a key role in identifying the astrophysical accelerators responsible for producing $\sim$ PeV particles and shaping the Galactic cosmic-ray population. SNR G69.7+1.0 has recently attracted attention due to its association with the LHAASO source 1LHAASO J2002+3244, which emits above 100 TeV. This spatial coincidence provides a unique opportunity to...
Since 2010, the JEM-EUSO (Joint Exploratory Missions for Extreme Universe Space Observatory) collaboration has been developing an ambitious program to observe Ultra-High-Energy Cosmic Rays (UHECRs) and related phenomena from space. These particles, with energies exceeding 10²⁰ eV, carry crucial information about the most extreme astrophysical environments, yet are difficult to study due to...
Ultra-high energy cosmic rays (UHECRs) above 100 PeV can be detected from space by looking towards the Earth's limb, where the optical emission from extensive air showers (EAS) can be observed. Space-based experiments can also play a crucial role in the multi-messenger astrophysics era, particularly through the detection of Earth-skimming neutrinos. Validating the observational techniques used...
The main objective of the international JEM-EUSO (Joint Exploratory Missions for Extreme Universe Space Observatory) Collaboration is to develop a large mission with dedicated instrumentation looking down on the Earth atmosphere from space, both towards nadir and/or towards the limb, to detect the Extensive Air Shower (EAS) and the High Altitude Horizontal Airshowers (HAHA) initiated by...
GRAND is a planned large-scale, worldwide radio array designed for autonomous self-triggered detection of ultra-high-energy cosmic rays and neutrinos. GRANDProto300 is one of pioneering prototype array of the GRAND experiment. It consists of 300 radio antennas and will cover an area of (200\, \text{km}^2) in a radio-quiet region of western China. Serving as a test bench for the GRAND...
We present the first experimental evidence for in-ice radiofrequency emission from cosmic-ray-induced high-energy particle cascades developing in the Antarctic ice sheet. In 208 days of data recorded with the phased-array trigger of the Askaryan Radio Array, we detect 13 events with impulsive radiofrequency pulses originating from below the ice surface. Considering only the arrival angles and...
The Radar Echo Telescope for Cosmic Rays (RET-CR) is a pathfinder experiment deployed at the Summit Station in Greenland, with a full data-taking run conducted in the summer of 2024. This experiment utilises the radar technique to search for an in-ice secondary cascade produced when the core of a high-energy cosmic ray air shower propagates into the high-altitude ice sheet.
Detecting a...
To detect ultra-high-energy neutrinos, experiments such as the Askaryan Radio Array (ARA) and the Radio Neutrino Observatoy in Greenland (RNO-G), target the radio emission induced by these particles as they cascade in the ice, using deep in-ice antennas at the South Pole or in Greenland. In this context, it is essential to first characterize the in-ice radio signature from cosmic-ray-induced...
