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Nello Vertolli

Publications and source records attributed to Nello Vertolli.

4 recordsLinked to original sources

GRINTA: a new Probe of the Dynamic Universe

Recent observations of the transient sky at all wavelengths are increasingly revealing the importance of the multi-messenger and multi-wavelength approach. The GRINTA (Gamma-Ray INternational Transient Array Observatory) mission, proposed for launch around the middle of the next decade, is conceived as a small mission with good sensitivity, excellent angular resolution and fast follow-up capability for studying transient sources at timescales from ms to hours, at the same time ensuring optimal integration with multi-messenger networks. The GRINTA mission will carry two complementary payloads to cover in total the 5 keV-10 MeV band, that will detect and localise gamma-ray bursts covering $\sim$ half of the sky and will be able to perform imaging surveys with sub-arcmin resolution. GRINTA will operate in synergy with the most powerful electromagnetic, gravitational wave and neutrino observatories foreseen to be operational after 2035.

astro-ph.IM

Conceptual framework for the application of deep neural networks to surface composition reconstruction from Mercury's exospheric data

Surface information derived from exospheric measurements at planetary bodies complements surface mapping provided by dedicated imagers, offering critical insights into surface release processes, interactions within the planetary environment, space weathering, and planetary evolution. This study explores the feasibility of deriving Mercury's regolith elemental composition from in-situ measurements of its neutral exosphere using deep neural networks (DNNs). We present a supervised feed-forward DNN architecture - a multilayer perceptron (MLP) - that, starting from exospheric densities and proton precipitation fluxes, predicts the chemical elements of the surface regolith below. It serves as an estimator for the surface-exosphere interaction and the processes leading to exosphere formation. Because the DNN requires a comprehensive exospheric dataset not available from previous missions, this study uses simulated exosphere components and simulated drivers. Extensive training and testing campaigns demonstrate the MLP's ability to accurately predict and reconstruct surface composition maps from these simulated measurements. Although this initial version does not aim to reproduce Mercury's actual surface composition, it provides a proof of concept, showcasing the algorithm's robustness and capacity for handling complex datasets to create estimators for exospheric generation models. Moreover, our tests reveal substantial potential for further development, suggesting that this method could significantly enhance the analysis of complex surface-exosphere interactions and complement planetary exosphere models. This work anticipates applying the approach to data from the BepiColombo mission, specifically the SERENA package, whose nominal phase begins in 2027.

astro-ph.EP

Gamma-Ray Burst observations by the high-energy charged particle detector on board the CSES-01 satellite between 2019 and 2021

In this paper we report the detection of five strong Gamma-Ray Bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite (CSES-01), operational since 2018 on a Sun-synchronous polar orbit at a $\sim$ 507 km altitude and 97$^\circ$ inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3 - 100 MeV, protons in the range 30 - 300 MeV, and light nuclei in the range 30 - 300 MeV/n. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV - 50 MeV, even if with a moderate effective area above $\sim$ 5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterised by a fluence above $\sim$ 3 $\times$ 10$^{-5}$ erg cm$^{-2}$ in the energy interval 300 keV - 50 MeV, have been detected.

astro-ph.HE

The BepiColombo SERENA/ELENA Instrument On-Ground Testing with the ELENA Special Check Out Equipment (SCOE)

The neutral particles sensor ELENA (Emitted Low Energy Neutral Atoms) for the ESA/JAXA BepiColombo mission to Mercury (in the SERENA instrument suite) is devoted to measure low energetic neutral atoms. The main goal of the experiment is measuring the sputtering emission from planetary surfaces, from E=20eV up to E=5keV, within 1D (2 deg. x 76 deg. ). ELENA original project had also a particle discrimination system based on Time-of-Flight (TOF) of particles through the shutter on the Micro Channel Plates detector (MCP), it has been withdrawn from the flight model due to design and development problems. The ELENA SCOE is the configuration/testing system of ELENA, it allows to command operations and to set up configuration parameters on the instrument and to monitor the incoming data. The TC/TM simulation/encoding/decoding software is developed respecting the CCSDS/ECSS standards implemented by ESA, and it's SCOS2000 compatible. TC generation, HK data monitoring and basic science data analysis are operated by the SERENA EGSE, developed by the Finnish Meteorological Institute (FMI), Helsinki, Finland. The data stream outcoming from the EGSE is then preprocessed from TM to user readable formats: FITS and then ASCII csv tables with metadata collected in a detached XML file, called label. This task is performed using the PacketLib, ProcessorLib, and DISCoS (PPD) framework and is going to be used as the first level prototype of the BepiColombo Science Ground Segment processing pipeline, based in ESAC, Madrid, Spain and implemented using the PDS4 data format.

astro-ph.IM