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

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

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

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

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 cos θr = 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

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

Nesting W-I Mirrors in a telescope

A Focusing X-ray Telescope Several nested W-I mirrors and coated in Ni, Au or Ir focalize grazing incident X-rays Into a focal 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.

Major Mirror X-ray Telescopes (untill 2000) 1999

XMM - Newton

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

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.

Imaging performances of XMM 110” 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)

XMM Performances Effective area of XMM mirrors plus focal plane instruments Typical spectra otained with XMM EPIC Calibration +background spectrum with XMM EPIC PN

The Chandra Observatory

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

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

source 1 masque codé détecteur sensible à la position

source 2 masque codé détecteur sensible à la position

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

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 OMC (visible band) IBIS γ-ray imager JEM-X (X-ray monitor) ISGRI camera SPI γ-ray spectrometer

IBIS: Imager onBoard Integral Satellite

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

Active X-Ray Missions MISSSION LAUNCH ENERGY OPTICS DETECTORS FOV Ang Res Area cm2 En.Res (eV) RXTE 1995 2-60 keV Collimator PropCount 1° 5000 1125 (6 keV) Chandra 1999 0.1 – 10 keV Mirrors CCD 17’ 0.5" 230 170 Newton 30’ 6" 850 130 INTEGRAL 2002 20 keV - 10 MeV Cod Mask CdTe Det Ge Det 30° 12’ 2000 (1MeV) SWIFT 2004 1 – 150 keV Mirror Suzaku 2005 0.1 – 700 keV Si Det 20’ 4.5° 1.5’ 1000 6 keV 120 MAXI (on ISS) 2008 2 - 30 keV Collimator (ASM) Gas PC Solid St. C 16 0° x 1.5° 1.5°

Same examples of Images obtained with X-ray Focussing Telescopes and Coded Mask hard X-ray / soft gamma-ray Telescopes

Chandra & XMM Surveys of the GC Commenting the talk

6.4 keV Neutral Iron K line

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

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/-0.10 keV Line width: 2.95+0.45/-0.51 keV (FWHM) Flux: (1.05±0.06)×10-3 ph cm-2 s-1

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.

X-Ray Astronomy Programmatics Chandra, XMM-Newton, INTEGRAL missions extended 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