End-to-end simulations of the MUon RAdiography of VESuvius experiment

The MUon RAdiography of VESuvius (MURAVES) project aims at the study of the summital cone of Mt. Vesuvius, an active volcano near Naples (Italy), by measuring its density profile through muon flux attenuation. Its data, combined with those from gravimetric and seismic measurement campaigns, will be used for better defining the volcanic plug at the bottom of the crater. We report on the development of an end-to-end simulation framework, in order to perform accurate investigations of the effects of the experimental constraints and to compare simulations, under various model hypotheses, with the actual observations. The detector simulation setup is developed using GEANT4 and a study of cosmic particle generators has been conducted to identify the most suitable one for our simulation framework. To mimic the real data, GEANT4 raw hits are converted to clusters through a simulated digitization: energy deposits are first summed per scintillator bar, and then converted to number of photoelectrons with a data-driven procedure. This is followed by the same clustering algorithm and same tracking code as in real data. We also report on the study of muon transport through rock using PUMAS and GEANT4. In this paper we elaborate on the rationale for our technical choices, including trade-off between speed and accuracy. The developments reported here are of general interest in muon radiography and can be applied in similar cases.

Radio interferometry applied to the observation of cosmic-ray induced extensive air showers

We developed a radio interferometric technique for the observation of extensive air showers initiated by cosmic particles. In this proof-of-principle study we show that properties of extensive air showers can be derived with high accuracy in a straightforward manner. When time synchronisation below $$\sim $$ ∼ 1 ns between different receivers can be achieved, direction reconstruction resolution of $$< 0.2^\circ $$ < 0 . 2 ∘ and resolution on the depth of shower maximum of $$<10$$ < 10 g/cm$$^2$$ 2 are obtained over the full parameter range studied, with even higher accuracy for inclined incoming directions. In addition, by applying the developed method to dense arrays of radio antennas, the energy threshold for the radio detection of extensive air showers can be significantly lowered. The proposed method can be incorporated in operational and future cosmic particle observatories and with its high accuracy it has the potential to play a crucial role in unravelling the composition of the ultra-high-energy cosmic-particle flux.

A new type of cloud discovered from Earth in the upper Martian atmosphere

&lt;p&gt;During the 2020 Mars opposition, we observe from Earth the occurrence of a non-typical large-scale high-altitude clouds system, extending over thousands of km from the equator to 50&amp;#176;S. Over 3 hours, they emerge from the night side at an altitude of 90 (-15/+30) km and progressively dissipate in the dayside. They occur at a solar longitude of 316&amp;#176;, west of the magnetic anomaly and concomitantly to a regional dust storm. Despite their high altitude, they are composed of relatively large particles, suggesting a probable CO&lt;sub&gt;2&lt;/sub&gt; ice composition, although H&lt;sub&gt;2&lt;/sub&gt;O cannot be totally excluded. Such ice clouds were not reported previously. We discuss the formation of this new type of clouds and suggest a possible nucleation from cosmic particle precipitation.&lt;/p&gt;

Cosmic Particle Accelerators

In the century since the measurements of Victor Hess [1]—considered as the discovery of cosmic rays—the properties of cosmic rays, as they arrive on Earth, have been studied in remarkable detail; we know their energy spectrum, extending to 1020 eV, their elemental composition, their angular distribution, and we understand the basic energetic requirements of cosmic ray production in the Galaxy.

The Effect of Deep N+ Well on Single-Event Transient in 65 nm Triple-Well NMOSFET

In a triple-well NMOSFET, a deep n+ well (DNW) is buried in the substrate to isolate the substrate noise. The presence of this deep n+ well leads to changes in single-event transient effects compared to bulk NMOSFET. In space, a single cosmic particle can deposit enough charge in the sensitive volume of a semiconductor device to cause a potential change in the transient state, that is, a single-event transient (SET). In this study, a quantitative characterization of the effect of a DNW on a SET in a 65 nm triple-well NMOSFET was performed using heavy ion experiments. Compared with a bulk NMOSFET, the experimental data show that the percentages of average increase of a SET pulse width are 22% (at linear energy transfer (LET) = 37.4 MeV·cm2/mg) and 23% (at LET = 22.2 MeV·cm2/mg) in a triple-well NMOSFET. This study indicates that a triple-well NMOSFET is more sensitive to a SET, which means that it may not be appropriate for radiation hardened integrated circuit design compared with a bulk NMOSFET.

The Cherenkov Telescope Array Science Goals and Current Status

The Cherenkov Telescope Array (CTA) is the major ground-based gamma-ray observatory planned for the next decade and beyond. Consisting of two large atmospheric Cherenkov telescope arrays (one in the southern hemisphere and one in the northern hemisphere), CTA will have superior angular resolution, a much wider energy range, and approximately an order of magnitude improvement in sensitivity, as compared to existing instruments. The CTA science programme will be rich and diverse, covering cosmic particle acceleration, the astrophysics of extreme environments, and physics frontiers beyond the Standard Model. This paper outlines the science goals for CTA and covers the current status of the project.