Geant4 simulation of the residual background in the ATHENA wide field imager from protons deflected by the charged particle diverter

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F22%3A00127120" target="_blank" >RIV/00216224:14310/22:00127120 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12181/2629994/Geant4-simulation-of-the-residual-background-in-the-ATHENA-wide/10.1117/12.2629994.short" target="_blank" >https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12181/2629994/Geant4-simulation-of-the-residual-background-in-the-ATHENA-wide/10.1117/12.2629994.short</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1117/12.2629994" target="_blank" >10.1117/12.2629994</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Geant4 simulation of the residual background in the ATHENA wide field imager from protons deflected by the charged particle diverter

Popis výsledku v původním jazyce

X-ray telescopes opened up a new window into the high-energy universe. However, the last generation of these telescopes encountered an unexpected problem: their optics focused not only x-rays but low-energy (so called soft) protons as well. These protons are very hard to model and can not be distinguished from x-rays. For example, 40% of XMM-Newton observations is significantly contaminated by soft proton induced background flares. In order to minimize the background from such low-energy protons the advanced telescope for high energy astrophysics (ATHENA) satellite introduced a novel concept, the so called charged particle diverter (CPD). It is an array of magnets in a Hallbach design, which deflects protons below 76 keV before they would hit the wide field imager (WFI) detector. In this work, we investigate the effect of scattering of the deflected protons with the CPD walls and the inner surfaces of the WFI detector assembly. Such scattered protons can loose energy, change direction and still hit the WFI. In order to adopt the most realistic instrument model, we imported the CAD model of both the CPD and the WFI focal plane assembly. Soft protons corresponding to ≈2.5 hours of exposure to the L1 solar wind are simulated in this work. The inhomogeneous magnetic field of the CPD is included in the simulation. We present a preliminary estimate of the WFI residual background induced by soft proton secondary scattering, in the case of the optical blocking filter present in the field of view. A first investigation of the volumes responsible for scattering the protons back into the field of view is reported.

Název v anglickém jazyce

Geant4 simulation of the residual background in the ATHENA wide field imager from protons deflected by the charged particle diverter

Popis výsledku anglicky

X-ray telescopes opened up a new window into the high-energy universe. However, the last generation of these telescopes encountered an unexpected problem: their optics focused not only x-rays but low-energy (so called soft) protons as well. These protons are very hard to model and can not be distinguished from x-rays. For example, 40% of XMM-Newton observations is significantly contaminated by soft proton induced background flares. In order to minimize the background from such low-energy protons the advanced telescope for high energy astrophysics (ATHENA) satellite introduced a novel concept, the so called charged particle diverter (CPD). It is an array of magnets in a Hallbach design, which deflects protons below 76 keV before they would hit the wide field imager (WFI) detector. In this work, we investigate the effect of scattering of the deflected protons with the CPD walls and the inner surfaces of the WFI detector assembly. Such scattered protons can loose energy, change direction and still hit the WFI. In order to adopt the most realistic instrument model, we imported the CAD model of both the CPD and the WFI focal plane assembly. Soft protons corresponding to ≈2.5 hours of exposure to the L1 solar wind are simulated in this work. The inhomogeneous magnetic field of the CPD is included in the simulation. We present a preliminary estimate of the WFI residual background induced by soft proton secondary scattering, in the case of the optical blocking filter present in the field of view. A first investigation of the volumes responsible for scattering the protons back into the field of view is reported.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

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, Volume 12181: Space Telescopes and Instrumentation 2022: Ultraviolet to Gamma Ray

ISBN

9781510653436

ISSN

0277-786X

e-ISSN

1996-756X

Počet stran výsledku

9

Strana od-do

1-9

Název nakladatele

SPIE

Místo vydání

Washington

Místo konání akce

Montréal

Datum konání akce

17. 7. 2022

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000865607100098