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Joint Discussion on the Highest-Energy Gamma-Ray Universe observed with Cherenkov Telescpe Arrays. The multi-wavelength context of the future gamma-ray instruments: X-rays. T. Dotani 1) , A. Bamba 2) , T. Fujinaga 3,1) 1) ISAS/JAXA 2) Aoyama Gakuin Univ. 3) Tokyo Institute of Technology.
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Joint Discussion on the Highest-Energy Gamma-Ray Universe observed with Cherenkov Telescpe Arrays The multi-wavelength context of the future gamma-ray instruments: X-rays T. Dotani1), A. Bamba2), T. Fujinaga3,1) 1) ISAS/JAXA 2) Aoyama Gakuin Univ. 3) Tokyo Institute of Technology
CONTENTS • Current/Future X-ray missions • NuSTAR, ASTROSAT, eROSITA, LOFT • ASTRO-H • Science cases : X-ray studies of VHE -ray sources • Shell-type SNRs • PWNe • Blazars
1-10 keV 1-10 TeV Complementarity of X-ray & VHE -ray bands Examples of SEDs from mono-energetic electrons/protons (Hinton, J.A., Hofmann, W., 2009. ARAA, 47, 523) E2dN/dE (erg/cm2/sec)
CTA schedule 2010 2015 2020 Preparatory phase Construction/Deployment Partial Operation Full Operation
X-ray satellites in these 10 years 2010 2015 2020 CTA Chandra XMM-Newton Suzaku NuSTAR ASTROSAT eROSITA/SRG ASTRO-H LOFT
Integral NuSTAR NuSTAR • Launched successfully on June 13th, 2012. • The first satellite-based focusing X-ray telescope operating in the hard X-ray band, 5-80 keV. Leading institution : Caltech Mission life : 2 years baseline Deployable mast Focal length 10m
ASTROSAT The first dedicated astronomy mission in India for multi-wavelength astronomy. Launch : 2013 Main instrument : large area proportional counter (6000 cm2) LAXPC
eROSITA / SRG eROSITA will be the primary instrument on-board the Russian "Spectrum-Roentgen-Gamma" (SRG) satellite. Purpose : First imaging all-sky survey up to 10 keV Launch : 2013 Leading institution : MPE
LOFT : the Large Observatory For X-ray Timing One of the four candidates selected for the next M-class mission in ESA’s Cosmic Vision. Current status : Assessment phase Launch period : 2020-2022 (if selected) Instruments • The Large Area Detector (10m2@8 keV) • The Wide Field Monitor
ASTRO-H Suzaku 6.5m • Length :14 m • Weight : 2.7 t • Power : 3500 W • Telemetry : 8Mbps (X-band) • Data Recorder : 12 Gbits • Launch : 2014 • Life : 3 year (requirement) • 5 year (goal) 14m H2A
SXS: cooling chain Life • 3 years with LHe • 2 more years without LHe
SXS performance compared with existing observatories Figure of merit Effective area
SXI: an X-ray CCD camera • 4 CCD chips with 31x31mm • Depletion layer: 200m • Type: Back-illumination • Operating temp.: -120 - -100 degC • Exposure time: 4 sec • FOV: 38x38 arcmin Engineering model Hood A focal plane assembly Frontend Electronics box SXI
Hard X-ray telescopes & imagers HXT principle
HXI: hard X-ray imagers principle BGO scintillaters Engineering model
BGO fov SGD Fine collimator fov Principle Narrow field Compton camera AE Fine collimator Satellite side panel BGO BGO SGD Compton camera
ASTRO-H sensitivities in hard X-ray band MeV keV GeV TeV 10-4 INTEGRAL Suzaku SGD SGD HXI CTA HXI 10-8 104 1010 1012 106 100 10 1000 Energy (eV) Energy (keV)
VHE -ray sky Galactic (61): PWN (19), -ray binary (4), SNR(10), GC (1), Pulsar (1), OC (1), unID (24) Extra-galactic (46) : Blazar (37), FSRG (2), Radio galaxy (5), SB galaxy (2) http://www.mpp.mpg.de/~rwagner/sources/
Origin of cosmic rays below ~1015 eV− Particle acceleration in shell type SNRs? − G347.3-0.5 (RX J1713.7-3946): shell-type SNR Model spectrum for the hadronic scenario TeV image with HESS Contours : ASCA Yuan, Q. et al. 2011, ApJ, 735, 120
Acceleration in thin filaments G347.3-0.5 Chandra SN1006 Chandra Red : 0.5-0.91 keV Cyan : 0.91-1.34 keV Blue : 1.34-3.0 keV Uchiyama et al. 2007, Nature, 449, 576
Expected image with A-H/HXI Structure of the particle acceleration site in the filaments may be studied with NuSTAR and A-H/HXI at an order of magnitude higher energies. Simulated image of A-H/SXI (9x9 arcmin2)
Measuring the ion temperature in shell type SNR SN1006 NW shell : thermal X-rays Kinematic energy of shocked plasma Kinematic energy of unshocked plasma Thermal energy of shocked plasma Shock velocity is known (2890 km/s) Particle acceleration ASTRO-H SXS can measure the thermal energy (ion temp) of shocked plasma Measure the particle acceleration efficiency
>3000 years 1000-3000 years <1000 years Evolution of particle acceleration in the shell-type SNRs Stefan Funk, August 5th 2011, TeVPA
Evolution of Synchrotron X-rays in SNRs Synchrotron X-rays tends to drop for SNRs with >5pc. Radius : indicator of age Nakamura et al. 2012, ApJ, 746, 134
Evolution of Synchrotron X-rays in SNRs Assumption (electrons) acceleration time = synchrotron cooling time TeV protons 0.1 cm-3 1 cm-3 Assumption (protons) Acceleration time = SNR age 5 cm-3 electrons
Diffusion of energetic electrons in PWNe G18.0-0.7 (HESS J1825-137) : spectral steepening away from the pulsar Produced by S. Funk and O.C. de Jager for the H.E.S.S. collaboration
An example of X-ray observations The Kookaburra complex HESS J1420-607 Suzaku X-ray image K3 PSR J1420-6048 (P=68ms) R1 & R2 HESS J1418-609 H.E.S.S. contours Rabbit
Spatial dependence of the X-rays in the PWN Energy spectra tend to become softer according to the distance from the X-ray peaks (pulsars). Energy loss of electrons/positrons due to the synchrotron radiation (Compton scattering) as they propagate. K3 Rabbit
Spatial dependence of the X-rays in the PWN (2) HESS J1846-029 (Kes75) HESS J1833-105 (G21.5-0.9) HESS J1747-281 (G0.9+0.1) HESS J1809-193 (G18.0-0.7) HESS J1825-137 HESS J1837-069 HESS J1804-216 HESS J1809-193 • Radio pulsar (82.7 ms) at the cross. • Spatial variation of the VHE photon index is suggested by H.E.S.S. HESS A A B B D C C D 2 2.5 Photon index
Suzaku observations of HESS J1809-193 Suzaku 0.4-1 keV 2-10 keV • X-ray source at the position of the pulsar • Different spatial distribution between thermal (0.4-1 keV) and non-thermal X-ray emission. HESS Energy spectra were calculated for annular regions (A through D)
HESS J1809-193 : spectral analysis Spectral model : Power-law + thin thermal X-ray emission NH = 7.1 ×1021 cm-2 kT = 0.18 keV Pulsar A B C D Far 1.5 2.0 Photon index No spatial dependence was found in the spectral shape
HESS J1809-193 : spatial extent Measure the extension of non-thermal X-ray emission around the pulsar Suzaku 1 2-10 keV Relative intensity 0.5 pulsar 0 5 10 15 20 Distance from the pulsar (arcmin) Projected intensity profile in the rectangle region Fit with a gaussian + constant σ = 6’.8 ±1’.0 Pseudo-color map : 2-10 keV X-ray intensity Yellow contours : HESS image
Spatial extent of the non-thermal emission Suzaku Chandra HESS J1825-137 PSR J1420-6049 σ = 3’.5 ±0’.4 σ = 1’.5 ±0’.4 ASCA Vela X MSH 15-52 Chandra σ = 23’.5 ±2’.6 σ = 1’.6 ±0’.1 35
Spatial extent of the non-thermal emission Suzaku Kes 75 Chandra HESS J1718-385 σ = 0’.63 ±0’.05 σ = 4’.2±0’.5 G21.5-0.9 Chandra XMM-Newton HESS J1616-508 σ = 0’.91 ±0’.05 σ = 1’.8 ±0’.5
Spatial extent of the non-thermal diffuse X-ray emission vs pulsar ages X-ray emitting electrons Energy loss time scale Accelerated electrons up to ~80 TeV can escape from the PWNe without losing most of the energies.
VHE -ray sky Galactic (61): PWN (19), -ray binary (4), SNR(10), GC (1), Pulsar (1), OC (1), unID (24) Extra-galactic (46) : Blazar (37), FSRG (2), Radio galaxy (5), SB galaxy (2) http://www.mpp.mpg.de/~rwagner/sources/
1-10 TeV 1-10 keV X-ray band is suited to detect luminous FSRQs Multi-frequency studies of Blazars Blazar sequence X-ray GeV TeV Radio Optical Flat Spectrum Radio Quasars (= FSRQ, e.g. PKS0528-134) ERC Sync SSC Low-frequency peaked BL Lac (= LBL e.g., 0716+714) High-frequency peaked BL Lac (= HBL e.g., Mrk421) Low-energy peak (Synchrotron) High-energy peak (Inverse Compton) LE HE Kataoka 02 Kubo+ 98
HXI 100ks High power jets : Luminous FSRQ PKS 2149-306 Fermi LAT LX > 2x1047 erg/sec (>109 Msolar SMBH) The best-fit synchrotron-Compton model for PKS 2149-306. CTA The model is shifted to z~8. Astro-H can detect wide-band spectrum of effectively all the luminous FSRQs. Soft X-ray Hard X-ray Evolution of FSRQs Ghisellini et al. 2010, MNRAS, 405, 387
CXB and contribution of the FSRQs FSRQs may explain the CXB at >500 keV solving the mystery of generation of the MeV background. FSRQs (double power-law is assumed) Seyfert-like AGNs Ajello, M. et al. 2009, ApJ, 699, 603
Summary • ASTRO-H may be the only observatory-class X-ray satellite operating simultaneously with CTA. • Combining ASTRO-H and CTA data, we may be able to trace history of particle acceleration, acceleration efficiency, and diffusion of energetic particles in SNRs and PWNe. • HXI on board ASTRO-H may be powerful telescopes to observe luminous FSRQs, which are key to understand CXB in the MeV band.