High energy perspectives (and conclusions) Philippe Ferrando APC Laboratory (UMR 7164) - Service d’Astrophysique CEA/Saclay APC Conference High Energy Phenomena in the Galactic CenterJune 17, 2005

The Galactic Centre : an exciting and growing field Exciting : closest look we can have to a Super Massive Black Hole and its complex surroundings in the Universe - Potential link with more distant AGNs potentially harboring dark matter, UHE cosmic-ray accelerator… Growing : New high quality high energy data : X-rays [0.1–10 keV]Chandra & XMM–Newton1999 -…  -rays [ MeV]Integral TeV  -rays [0.1–20 TeV]HESS Multi Wavelength Campaigns with radio and NIR

Chandra & XMM–Newton Angular resolution : resolving this complex region, and measuring the quiescent spectrum of SgrA* High throughput : detailed spectro-imaging up to 10 keV

Chandra and XMM–Newton Sensitivity : acces to short time variability +0.5° Continuum subtracted line emission Sulphur KFe K 6.7 keV 4-6 keV Radio VLA Galactic Latitude X-ray flares from SgrA*, look for periodicity…

INTEGRAL Sensitivity and angular resolution : mapping this complex region IBIS/ISGRI mosaics in different energy bands: spectrum keV Possible shift of the central source between Sgr A and 1E keV keV keV keV

HESS Sensitivity, angular resolution, large Field of View H.E.S.S. Preliminary

But questions still open… What makes the 6.4 keV line ? Nature of hot component ?Origin of the large scale 511 keV line ?

But questions still open… Integral How many sources ? Spectrum of SgrA* ? Are Ultra High Energy Cosmic Rays accelerated at the GC ?

What can we count on for sure ? Gamma-ray sources and UHECR connection AGASA excess map in the a posteriori energy band [ – ] eV 15° GC Completion in 2006 Unprecedented statistics expected Angular resol. 0.5–1° GC and AGASA/Sugar prime targets ? AUGER

What can we count on for sure ? Gamma-ray - Neutrinos connection ANTARES Completion in 2007 Max of signal ~ 10 TeV Very low bckgd for point sources Angular 10 TeV ~ 0.2° Expected rate (HESS) very low 0.02 evt/year but surprises possible… Clear need for a km3 experiment in a longer term

What can we count on for sure ? AGILE gamma-ray telescope Small ASI mission - launch date early 2006 Anticoincidence SuperAGILE Si tracker Mini- Calorimetre GRID : E-range : 30 MeV – 30 GeV FoV2.5 sr  36 1 GeV Improve EGRET error box radius by a factor of 2

What can we count on for sure ? GLAST/LATEGRET E range : GeV E resolution :10 %10 % Eff. Area :8000 cm21500 Field of view> 2 sr0.5 sr Ang. Resol. ~ MeV5.8° ~ 0.15 o > 10 GeV Sensitivity<6 x cm -2 s -1~ Source locat arcmin5–30 The GLAST mission : launch mid 2007 Orders of magnitude improvement upon EGRET

What can we count on for sure ? Upgrade : HESS II Lower threshold to extend the energy-range in mono-telescope mode Better sensitivity at high energies in stereo Reduce GC source position uncertainty now 4'' ± 10'' stat ± 20'' syst from Sgr A* (1 pc) Atmospheric Cerenkov ( stress on HESS but also MAGIC, VERITAS, CANGAROO )

What can we count on for sure ? Full spectral coverage in gamma-rays ! Connection space-ground Variability

And in a longer term ? An absolute necessity : get the angular resolution and the sensitivity down by orders of magnitude above 10 keV

XMM-Newton GC Survey0.3-9 keV 0.0° 359.0°1.0° INTEGRAL GC Survey20-40 keV (Belanger et al 2005, in prep.) (Decourchelle et al. 2003) Sgr A Sgr B2

The 10 keV sensitivity gap reason 0.1–10 keV : focusing optics Spatial resolution : 15 arcsec High signal to noise XMM–Newton 15 keV–10 MeV : coded masks Spatial resolution : 12 arcmin Moderate signal to noise INTEGRAL

The necessary future : use focusing optics as in longer wavelengths In hard X-rays : feasible on a large energy range by extension of the « usual » soft X–rays techniques Focusing using a grazing incidence nested shells Wolter I mirror Long focal length for high reflectivity at high energy Projects NuSTAR and SIMBOL-X

Basically : long focal length telescope, using grazing incidence X–ray optics, with mirror and detectors mounted on two different spacecraft in formation flying. Characteristics Energy range :0.5–70 keV Resolution :< keV, 1 60 keV Angular resol. :< 30 arcsec (local. < 3 arcsec) Effective area :>550 cm 2 E < 35 keV 150 cm 50 keV Sensitivity : ph/cm 2 /s/keV (E < 40 keV) (5 , 100 ks,  E = E/2) The Simbol-X mission

Optics (nominal) Direct heritage from XMM–Newton Long focal length for high reflectivity at high energy Nickel shells with single layer Pt coating, obtained by well proven electroforming replication method Low mass obtained via a reduced thickness of shells  : ~ 30’’ HEW FOV : ~ 6 arcmin 580 cm 30 keV Shell diameters : 290 to 600 mm Focal length : 30 m Angles :0.07° to 0.142° Shell thickness : 0.12 to 0.30 mm Number of shells :100 Total mass :213 kg

CdZnTe SDD < 17 keV> 17 keV Low energy detector (450  m Silicium) High energy detector (2 mm Cd(Zn)Te) Optical filter (0.1  m Al) Anticoincidence (BGO) Requirements Pixel size of ~ 500  m (gives good oversampling of the 4.4 mm PSF) Full diameter of focal plane : 6 cm Fast response detectors for full anticoincidence scheme Avoid constraining cooling Low energy response down to 0.5 keV Good spectral resolution for Iron line Focal plane SDD CdZnTe

Sensitivity 1 arcmin diameter region, 1 Ms exposure,  E = E/2 XMMINTEGRALSIMBOL-X

The central 2 degrees > 20 keVtoday 1.0° INTEGRAL GC Survey keV Sgr A Sgr B2 0.0° 359.0° in 2012 with Simbol-X

SIMBOL-X 3 , 1 hour Testing accretion models with SIMBOL-X Measurement of spectra for a large range of flare intensities Access to the high energy range, discriminating models Quiescent spectrum at ~ 40 keV Liu & Melia, 2002

Galactic Centre Diffuse Emission (Decourchelle et al. 04)

Galactic Centre seen by SIMBOL-X Spectrum in a 1 arcmin2 region Exposure time = 84 ks Simulation > 10 keV, 10 x 10 arcmin2 Total exposure = 300 ks (A. Decourchelle & J. Ballet)

Simbol–X status Selected by CNES for phase 0 assessment (4 missions kept) Phase A start, autumn 2005 (2 missions kept) Selection end 2006 (1 mission kept) Consortium led by France with a strong Italian involvment, and a firm participation of Germany Mission proposed early 2004 to CNES in response to a call for scientific missions using spacecrafts in formation flying Launch date : years of science observations

Conclusions The Galactic Centre an exciting and growing field, with a rich future ! A lot of important results to come in the next years, but will not solve all questions A deeper look possible early next decade with currently designed new generation of instruments