1 / 31

Instrumentation for X-Ray Astronomy

A. Goldwurm. CR Workshop – Leiden (H), 14 – 18 / 03 / 2011. 1. Instrumentation for X-Ray Astronomy. A. Goldwurm AstroP articule et Cosmologie Service d’Astrophysique / CEA – Saclay France. Specific Issues of X-ray Astronomy.

madge
Download Presentation

Instrumentation for X-Ray Astronomy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A. Goldwurm CR Workshop– Leiden (H), 14 – 18 / 03 / 2011 1 Instrumentation for X-Ray Astronomy • A. GoldwurmAstroParticuleet Cosmologie • Service d’Astrophysique / CEA – SaclayFrance

  2. Specific Issues of X-ray Astronomy • Earth atmosphere is opaque to X-rays => balloons, rockets or satellites needed • Optics: difficult or even impossible to focalize X-rays • Detectors of Photoelectric and Compton interactions • Sources have intrinsically weak photon fluxes (non-thermal spectra or HE tail of thermal very hot medium) • Detectors sensitive to particles and particle-generated X-rays => high level of background => Low S/N ratios

  3. The early days of X-ray Astronomy • X-ray astronomy starts after the WW II • 1962 discovery of the 1st extra-solar X-ray source with Sounding Rocket det • 1970 First X-ray satellite Uhuru • Instruments based on Proportional Counters + collimators • End of ’70s : focusing telescopes

  4. Jacques Paul L’observatoire spatial INTEGRAL – Lycée Arago – Perpignan Planche 4 Focalisation of Soft X-rays X and gamma - rays radio, IR, visible, UV waves Soft X - rays

  5. X-ray Grazing incidence reflection • Since EX > Eebind then refraction index for X-rays nX< 1 => it exists an incident angle of total external reflection (grazing angle) given by cosθr= nX • For nX= (1-δ), θr = (2δ)½ with δ = N0Zreρλ2/A 2π (e.g. Giacconi+ 69) • For Heavy Elements Z/A ~ 0.5 and therefore θr ρ1/2/ EX • Good reflectors are Au, Ni, Ir, Pt and critical angle are in the range 10’ - 2° for X-rays of 0.1 to 10 keV

  6. WOLTER Type I X-ray Mirror System 1 Paraboloid + 1 Hyperboloid polished and coated mirrors Emax = k f/D keV for D=1 m diameter & f=10 m focal length => Emax~ 10 keV

  7. Nesting W-I Mirrors in a telescope

  8. A Focusing X-ray Telescope • Several nested W-I mirrors and coated in Ni, Au or Ir focalize grazing incident X-rays • Into afocal plane position sensitive detector, e.g. a CCD for X-rays • Images are formed with effective area given by nested mirrors and a low background that depends on the detector volume.

  9. Major Mirror X-ray Telescopes(untill 2000) 1999

  10. XMM - Newton

  11. XMM Optical System and the Reflection Grating Spectrometer 70 cm 58 mirror shells 0.5 – 1 mm thick

  12. Images from XMM Newton EPIC • Observations: stabilized pointing of target sources for typical exposures of 5 - 200 ks • Data are in form of event lists (x, y, t, E) • Analysis: correct, filter, bin and combine event lists into images, spectra, light curves, and then derive source parameters.

  13. Imaging performances of XMM • Images of a point source by the 3 EPIC cameras (MOS1 MOS2 and PN) • PSF as function of distance from source: 6" (FWHP), 15" (HEW) 110”

  14. XMM Performances • Effective area of XMM mirrors plus focal plane instruments • Typicalspectraotainedwith XMM EPIC • Calibration +background spectrumwith XMM EPIC PN

  15. The Chandra Observatory

  16. And … for E > 10-15 keV ? The concept of a Pinhole camera

  17. The concept of Coded Mask Imaging source à l’infini masque codé détecteur sensible à la position

  18. source 1 masque codé détecteur sensible à la position

  19. source 2 masque codé détecteur sensible à la position

  20. The ESA INTEGRAL Mission A Gamma Ray Observatory 2 main -ray Telescopes Energy: 15 keV – 8 MeV High angular res.: ~ 12’ (IBIS) High spectral Res: DE/E ~=500 (SPI) + 2 Monitors (opt, X) • Launched with a Proton on 17/10/2002 • The First Gamma-Ray OBSERVATORY for the Astronomical Community

  21. OMC (visible band) JEM-X (X-ray monitor) IBIS γ-ray imager ISGRI camera SPI γ-ray spectrometer IBIS / ISGRI Performances Energy Band 20 keV-1 MeV Angular Resolution 12’ FOV at 100% s. 9° x 9° at 0 sensitivity 29° x 29° Point Source Location Err. 30” (S/N~30) Temporal resolution 60 s 100 keV Sensitivity (ph cm-2 s-1 keV-1) 4 10-7 (for 106 s, 3, E=E) 1 mCrab Narrow line sens. (cm-2 s-1) 10-5 Spectral resolution 8 keV

  22. IBIS: Imager onBoard Integral Satellite

  23. IBIS Data Analysis Reconstructed Sky Mask Pattern Detector Image Sum of Sky Images

  24. Active X-RayMissions

  25. Sameexamples of Images obtainedwith X-ray FocussingTelescopesand CodedMask hard X-ray / soft gamma-ray Telescopes

  26. Chandra & XMM Surveys of the GC

  27. 6.4 keV Neutral Iron K line

  28. 0.0° XMM-Newton GC Survey 0.3-9 keV 0.0° (Belanger et al. 2006) (Decourchelle et al. 2003) Sgr A INTEGRAL GC Survey 20-40 keV Sgr B2 0.0° 1.0° 359.0°

  29. INTEGRAL / SPI 511 keV Line • Spherical shape (Bulge) • 2D Gaussian profile with FWHM ~ 8º • Positronium fraction: 0.91 - 0.97 • Annihilation in warm ionized medium • Origin of positrons unknown • Originated at the GC ? (Knodelseder et al. 2004, Churazov etal 04, Jean etal 2005, ..) • Centroid: • 511.06+0.17/-0.10keV • Line width: • 2.95+0.45/-0.51keV (FWHM) Flux: (1.05±0.06)×10-3 ph cm-2 s-1

  30. Perspectives and Future Missions • Focalization at E > 10 keV, using multilayer coating + long focal L (> 10 m) with extendable mats or formation flying: • Nu-Star (US, 2013) Astro-H (JAXA, +, 2014): Emax ~ 80 keV but Ang.Res > 40’ • Several non-selected EU projects: Simbol-X (F-I), COSPIX (M3), NHXM (M3) • Focal-Plane Micro-calorimeters for high spectral res.: Astro-H (and IXO) • Light mirrors (glass layers, silicon pore layers) to obtain large effective areas and sensitivities (IXO) • Small / medium missions: X-ray polarimeters (GEM US 2014) or Large sensitive areas for timing / spectral studies (LOFT) • Coded masks for HE monitoring of transients and GRBs (SVOM Ch – F 2014) • Compton telescopes and Bragg diffusion lenses (M3) for the 1 MeV range.

  31. X-Ray Astronomy Programmatics • Chandra, XMM-Newton, INTEGRAL missionsextended to 2014 • Nu-Star, Astro H, SRG, GEM in development phase • IXO delayed by US Decadal to after 2025 • In competition for ESA Cosmic Vision Large class Mission (decision 2011) • No HE mission in the ESA Medium class Missions M1/M2 Missions (Launch 2018) • 1 HE mission selected for the ESA M3 call (L 2020): LOFT

More Related