28 research outputs found
Caratterizzazione delle sonde elettrostatiche CIRA presso IAPS
Le misurazioni della densità di corrente ionica nel plasma o nel fascio ionico di dispositivi di propulsione
elettrica per veicoli spaziali sono di grande rilevanza, in quanto il flusso di ioni espulsi determina le
caratteristiche del propulsore come spinta, impulso specifico e utilizzo del propellente, nonché le
prestazioni dell’intero sistema di propulsione.
Inoltre, una conoscenza accurata e completa della corrente ionica è fondamentale per la validazione di
modellazione della plume e per le simulazioni numeriche, per prove di accettazione dei propulsori, per lo
studio degli effetti di impianto e per comprendere le interazioni tra plasma e veicolo spaziale.
In questa attività si mettono a confronto tre diverse tipologie di sonde: una sonda planare con
guard-ring (sonda di Faraday), una sonda planare con collimatore (coppa di Faraday) e due
sonde di Langmuir di tipo cilindrico.
Nell'ambito dell'Accordo Quadro di mutua collaborazione scientifica tra INAF-IAPS e CIRA (2021), gli obiettivi principali di questo studio sono la caratterizzazione delle sonde elettrostatiche CIRA e
l'identificazione delle caratteristiche della diagnostica che permettono una più chiara/efficiente valutazione della
propulsione. Lo studio fornisce anche raccomandazioni per la corretta progettazione di una sonda di corrente ionica di alta qualità , nonché indicazioni per il funzionamento delle sonde e il trattamento dei dati
ELENA instrument science and testing: validation with particle beam
Understanding of particle emission processes from the Mercury surface is one of the major objectives of ELENAinstrument in the SERENA experiment on board of the BepiColombo mission. In particular the Ion-Sputteringprocess resulting from charged and energetic particles impacting on the surface can be investigated detectingthe low energetic neutral particles escaping from the planet. The possibility to identify the Ion-Sputtering signaltogether with back-scattered particles and neutrals generated by charge exchange is strictly linked with the newtechnology capability to measure low energetic neutral atoms. This goal can be addressed thanks to a new&oldapproach for the neutral atoms measurement: a well known Time of Flight system enhanced with a new kind ofStart section able to define the start time of the entrance in the ToF path without interacting with the particles anddirectly follow to the Stop detector. The Start section is a shutter composed by two membranes with nanometricslits realized in a large area (1cm2) and oscillating at several frequencies to open and close the entrance of ToFsection. This system is never used before in space mission.The IFSI-INAF Ion beam facility in Rome is devoted to the ELENA testing. The crucial point of the shutteringsystem interaction with particle beam is investigated. The first results demonstrate the good functionality of thiskind of system: capability of the shutter to Open and Close the entrance respect to an ion beam is tested with aMCP stop detector. In this poster we present the IFSI activity in the frame of ELENA science requirement togetherwith the experimental activity devoted to instrument verification
Performance analysis of the GR712RC dual-core LEON3FT SPARC V8 processor in an asymmetric multi-processing environment
In this paper we present the results of a series of performance tests carried out on a prototype board mounting the Cobham Gaisler GR712RC Dual Core LEON3FT processor. The aim was the characterization of the performances of the dual core processor when used for executing a highly demanding lossless compression task, acting on data segments continuously copied from the static memory to the processor RAM. The selection of the compression activity to evaluate the performances was driven by the possibility of a comparison with previously executed tests on the Cobham/Aeroflex Gaisler UT699 LEON3FT SPARCâ„¢ V8. The results of the test activity have shown a factor 1.6 of improvement with respect to the previous tests, which can easily be improved by adopting a faster onboard board clock, and provided indications on the best size of the data chunks to be used in the compression activity
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 507 km altitude and 97
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 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
3 10 erg cm in the energy interval 300 keV - 50
MeV, have been detected.Comment: Accepted for publication in The Astrophysical Journal (ApJ
ELENA FS vibration test report
ELENA FS (part of SERENA package for Bepi Colombo mission to Mercury) has been refurbished.
Vibration test has been planned to validate the insturment before ESA delivery. This document reports ELENA FS vibration test: selected test are resonance research and comparison with
the resonance spectra obtained at previous vibration test in November 201
ELENA DAC ramp test
Test report della campagna dello strumento SERENA/ELENA a bordo di BepiColomb
ELENA SW threshold for anodes 1-4 in Extended Histogram mode
Test Report modo scientifico dello strumento SERENA/ELENA a bordo della missione BepiColomb
ELENA representative shutter with glue thermal test
Description of thermal test of representative ELENA shutter with 3 point of glue at IAPS TV Facilit
ELENA FS test for on board procedure
Test Report di debug delle procedure sullo strumento SERENA/ELENA Flight Spare da eseguire a bordo della missione BepiColomb