Skip navigation
  • INAF logo
  • Home
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects
  • Explore by
    • Research outputs
    • Researchers
    • Organization units
    • Projects
  • Login:
    • My DSpace
    • Receive email
      updates
    • Edit Account details
  • Italian
  • English

  1. OA@INAF
  2. PRODOTTI RICERCA INAF
  3. 3 CONTRIBUTI IN ATTI DI CONVEGNO (Proceedings)
  4. 3.01 Contributi in Atti di convegno
Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12386/26582
Title: Monte Carlo simulations of soft proton flares: testing the physics with XMM-Newton
Authors: FIORETTI, VALENTINA 
BULGARELLI, ANDREA 
MALAGUTI, GIUSEPPE 
SPIGA, Daniele 
TIENGO, ANDREA
Issue Date: 2016
Volume: Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray
Editors: den Herder, Jan-Willem A.; Takahashi, Tadayuki; Bautz, Marshall
Series: PROCEEDINGS OF SPIE 
Number: 9905
First Page: 99056W
Abstract: Low energy protons (< 100 - 300 keV) in the Van Allen belt and the outer regions can enter the field of view of X-ray focusing telescopes, interact with the Wolter-I optics, and reach the focal plane. The funneling of soft protons was discovered after the damaging of the Chandra/ACIS Front-Illuminated CCDs in September 1999 after the first passages through the radiation belt. The use of special filters protects the XMM-Newton focal plane below an altitude of 70000 km, but above this limit the effect of soft protons is still present in the form of sudden ares in the count rate of the EPIC instruments that can last from hundreds of seconds to hours and can hardly be disentangled from X-ray photons, causing the loss of large amounts of observing time. The accurate characterization of (i) the distribution of the soft proton population, (ii) the physics interaction at play, and (iii) the effect on the focal plane, are mandatory to evaluate the background and design the proton magnetic diverter on board future X-ray focusing telescopes (e.g. ATHENA). Several solutions have been proposed so far for the primary population and the physics interaction, however the difficulty in precise angle and energy measurements in laboratory makes the smoking gun still unclear. Since the only real data available is the XMM-Newton spectrum of soft proton flares in orbit, we try to characterize the input proton population and the physics interaction by simulating, using the BoGEMMS framework, the proton interaction with a simplified model of the X-ray mirror module and the focal plane, and comparing the result with a real observation. The analysis of ten orbits of observations of the EPIC/pn instrument show that the detection of flares in regions far outside the radiation belt is largely influenced by the different orientation of the Earth's magnetosphere respect with XMM-Newton'os orbit, confirming the solar origin of the soft proton population. The Equator-S proton spectrum at 70000 km altitude is used for the proton population entering the optics, where a combined multiple and Firsov scattering is used as physics interaction. If the thick filter is used, the soft protons in the 30-70 keV energy range are the main contributors to the simulated spectrum below 10 keV. We are able to reproduce the proton vignetting observed in real data-sets, with a 50% decrease from the inner to the outer region, but a maximum flux of 0:01 counts cm<SUP>2</SUP> s<SUP>-1</SUP> keV<SUP>-1</SUP> is obtained below 10 keV, about 5 times lower than the EPIC/MOS detection and 100 times lower than the EPIC/pn one. Given the high variability of the are intensity, we conclude that an average spectrum, based on the analysis of a full season of soft proton events is required to compare Monte Carlo simulations with real events.
Conference Name: Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray
Conference Place: Edinburgh, United Kingdom
Conference Date: 26 June - 1 July 2016
URI: http://hdl.handle.net/20.500.12386/26582
URL: http://arxiv.org/abs/1607.05319v1
https://www.spiedigitallibrary.org/conference-proceedings-of-spie/9905/1/Monte-Carlo-simulations-of-soft-proton-flares--testing-the/10.1117/12.2232537.full?SSO=1
ISSN: 0277-786X
ISBN: 9781510601901
9781510601895
DOI: 10.1117/12.2232537
Bibcode ADS: 2016SPIE.9905E..6WF
Fulltext: open
Appears in Collections:3.01 Contributi in Atti di convegno

Files in This Item:
File Description SizeFormat 
SPIE99056W.pdfPdf editoriale1.56 MBAdobe PDFView/Open
Show full item record

Page view(s)

19
checked on Jan 25, 2021

Download(s)

2
checked on Jan 25, 2021

Google ScholarTM

Check

Altmetric


Items in DSpace are published in Open Access, unless otherwise indicated.


Explore by
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects

Informazioni e guide per autori

https://openaccess-info.inaf.it: tutte le informazioni sull'accesso aperto in INAF

Come si inserisce un prodotto: le guide a OA@INAF

La Policy INAF sull'accesso aperto

Documenti e modelli scaricabili

Feedback
Built with DSpace-CRIS - Extension maintained and optimized by Logo 4SCIENCE