Athena charged particle diverter simulations: effects of micro-roughness on proton scattering using Geant4

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F22%3APU147314" target="_blank" >RIV/00216305:26620/22:PU147314 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12181/2630076/Athena-charged-particle-diverter-simulations--effects-of-micro-roughness/10.1117/12.2630076.short?SSO=1" target="_blank" >https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12181/2630076/Athena-charged-particle-diverter-simulations--effects-of-micro-roughness/10.1117/12.2630076.short?SSO=1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1117/12.2630076" target="_blank" >10.1117/12.2630076</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Athena charged particle diverter simulations: effects of micro-roughness on proton scattering using Geant4

Popis výsledku v původním jazyce

The last generation of X-ray focusing telescopes operating outside the Earth's radiation belt discovered that optics were able to focus not only astrophysical X-ray photons, but also low-energy heliophysical protons entering the Field of View (FOV). This "soft proton" contamination affects around 40% of the observation time of XMMNewton. The ATHENA Charged Particle Diverter (CPD) was designed to use magnetic fields to move these soft protons away from the FOV of the detectors, separating the background-contributing ions in the focused beam from the photons of interest. These magnetically deflected protons can hit other parts of the payload and scatter back to the focal plane instruments. Evaluating the impact of this secondary scattering with accurate simulations is essential for the CPD scientific assessment. However, while Geant4 simulations of grazing soft proton scattering on X-ray mirrors have been recently validated, the scattering on the unpolished surfaces of the payload (e.g. the baffle or the diverter itself) is still to be verified with experimental results. Moreover, the roughness structure can affect the energy and angle of the scattered protons, with a scattering efficiency depending on the specific target volume. Using Atomic Force Microscopy to take nanometer-scale surface roughness measurements from different materials and coating samples, we use Geant4 together with the CADMesh library to shoot protons at these very detailed surface roughness models to understand the effects of different material surface roughnesses, coatings, and compositions on proton energy deposition and scattering angles. We compare and validate the simulation results with laboratory experiments, and propose a framework for future proton scattering experiments.

Název v anglickém jazyce

Athena charged particle diverter simulations: effects of micro-roughness on proton scattering using Geant4

Popis výsledku anglicky

The last generation of X-ray focusing telescopes operating outside the Earth's radiation belt discovered that optics were able to focus not only astrophysical X-ray photons, but also low-energy heliophysical protons entering the Field of View (FOV). This "soft proton" contamination affects around 40% of the observation time of XMMNewton. The ATHENA Charged Particle Diverter (CPD) was designed to use magnetic fields to move these soft protons away from the FOV of the detectors, separating the background-contributing ions in the focused beam from the photons of interest. These magnetically deflected protons can hit other parts of the payload and scatter back to the focal plane instruments. Evaluating the impact of this secondary scattering with accurate simulations is essential for the CPD scientific assessment. However, while Geant4 simulations of grazing soft proton scattering on X-ray mirrors have been recently validated, the scattering on the unpolished surfaces of the payload (e.g. the baffle or the diverter itself) is still to be verified with experimental results. Moreover, the roughness structure can affect the energy and angle of the scattered protons, with a scattering efficiency depending on the specific target volume. Using Atomic Force Microscopy to take nanometer-scale surface roughness measurements from different materials and coating samples, we use Geant4 together with the CADMesh library to shoot protons at these very detailed surface roughness models to understand the effects of different material surface roughnesses, coatings, and compositions on proton energy deposition and scattering angles. We compare and validate the simulation results with laboratory experiments, and propose a framework for future proton scattering experiments.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20301 - Mechanical engineering

Projekt

<a href="/cs/project/LM2018110" target="_blank" >LM2018110: Výzkumná infrastruktura CzechNanoLab</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Proceedings of SPIE

ISBN

978-1-5106-5344-3

ISSN

—

e-ISSN

—

Počet stran výsledku

12

Strana od-do

„“-„“

Název nakladatele

SPIE-INT SOC OPTICAL ENGINEERING

Místo vydání

BELLINGHAM

Místo konání akce

Montreal

Datum konání akce

17. 7. 2022

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000865607100101