Suzaku Observations of HESS sources Hironori Matsumoto (Kyoto - - PowerPoint PPT Presentation

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Suzaku Observations of HESS sources

Hironori Matsumoto (Kyoto Univ.)

Hideki Uchiyama (Kyoto Univ.), Aya Bamba, Ryoko Nakamura, Takayasu Anada (ISAS/JAXA), and the Suzaku team

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Outline

• HESS unID objects: “Dark particle accelerators”
• Suzaku Observations

– HESSJ1614-518 – HESSJ1616-508 – HESSJ1713-381 (CTB37B) – HESSJ1804-216 – HESSJ1825-137 – HESSJ1837-069

• Summary

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HESS Galactic Plane Survey

First systematic Galactic plane survey with TeV γ-ray (>200GeV) New TeV objects with no obvious counterpart.

(Aharonian et al. 2005, 2006)

HESSJ1804-216 HESSJ1616-508 HESSJ1614-518

• Gal. Cent.

HESSJ1713-381 HESSJ1837-069

Dark particle accelerators

HESSJ1825-137

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HESSJ1614-518

(l, b)=(331.52, -0.58)

HESS TeV γ-ray image (excess map)

XIS FOV 50ks Brightest among the new objects. HESSJ1614

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XIS FI (S0+S2+S3): 3-10keV band Extended object

TeVγ-ray

XIS image

Swift XRT also detected (Landi et al. 2006)

• Obs. 50ks

Src A Src B

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XIS spectra

NH=1.2(±0.5)e22cm-2 Γ=1.7(±0.3） F(2-10keV)=5e-13erg/s/cm2 NH=1.2(±0.1)e22cm-2 Γ=3.6(±0.2） F(2-10keV)=3e-13erg/s/cm2

• Featureless

non-thermal Featureless, but extremely soft

Src A Src B Src A spectrum Src B spectrum

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H.E.S.S. src A B=10μG B=1μG B=0.1μG

Src A Src B

Src A F(1-10TeV)/F(2-10keV)=34

Plausible X-ray counterpart: src A

Matsumoto et al. 2008, PASJ, 60. S163 (Suzaku special issue No.2)

• Difficult to explain both the TeV gamma-ray and X-ray from

the electron origin.

• The origin of srcA is not clarified.

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HESSJ1616-508

HESS TeV image (excess map)

(l, b)=(332.391, -0.138) XIS FOV 45ks

Provided by S. Funk (MPI)

HESSJ1616

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XIS image

XIS FI (S0+S2+S3): 3—12keV

• No X-ray counterpart
• F(2-10keV)<3.1e-13 erg/s/cm2

TeV image

45ks F(TeV)/F(X)>55

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If we assume electrons…

Very weak B (B<1μGauss)

HESSJ1616 SED Suzaku upper limit

Strong cut-off

• r

realistic?

Matsumoto et al. 2007, PASJ, 59, 199 (Suzaku Special Issue No.1)

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PSRJ1617-5055?

INTEGRAL 18-60keV PSRJ1617 Landi et al. 2007 XMM-Newton 0.5-10keV PSRJ1617 Why is there no trace in X-ray band? Why is there no clear PWN in the radio (Kaspi et al. 1998) and X-ray bands? SNR RCW103

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HESSJ1713-381 (CTB37B)

SNR CTB37B

HESSJ1713-381 coincides with the SNR CTB37B

Color: TeV White: radio

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Non-thermal hard X-ray

Nakamura 2008 in preparation

Suzaku 0.3-3.0keV Suzaku 3.0-10.0keV

Green: TeV (HESS) Blue: radio White: X-ray (Suzaku) reg1 reg1 reg2 reg2 Foreground src

Reg1: coincides with the TeV peak Reg2: offset hard emission

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Suzaku 3.0-10.0 keV

reg1 reg2

• Thermal (kT=0.9keV)+PL(Γ=3.0)
• A point source discovered by Chandra

(Aharonian et 1l. 2008) contributes much to the PL component. Hard PL (Γ=1.5) + Leakage from reg1 due to PSF.

• Roll-off energy > 15keV
• The hard PL suggests efficient acceleration.

F(TeV)/F(X)~0.2 B~8uG assuming IC. Emax > 170 TeV

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HESSJ1804-216

HESS TeV γ-ray image (excess map)

Provided by S. Funk (MPI)

(l, b)=(8.401, -0.033) XIS FOV 40ks Softest TeV spectrum among the new objects. HESSJ1804

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XIS image

XIS FI (S0+S2+S3): 3-10keV src1 src2 src1: point-like src2: extended

• r multiple

TeV image

40ks

Swift XRT (Landi et al. 2006) Chandra (Kargaltsev et al. 2007)

Chandra (Kargaltsev et al. 2007)

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XIS spectra

src1 src2 src1: point-like src2: extended

11±8 0.2(<2.2) NH (1022cm-2) 4.3 2.5 F(2-10keV) 10-13erg/s/cm2 1.7±1.2

• 0.3±0.5

Γ src2 src1

See Bamba et al. 2007, PASJ, 59, S209 (Suzaku Special Issue No.1)

F(TeV)/F(X) 50 25

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HESS J 1825-137

30arcmin~30pc @4kpc

HESS J1825-137

Aharonian et al. 2006 H.E.S.S TeV γ excess map PSR J1826-1334

Distance from Pulsar (deg) Photon Index Γ

IC by high-energy electrons from the pulsar?

• Spin-down luminosity

~ 2.8×1036 erg s-1

• Characteristic age

21.4 kyr (Clifton 1992)

• D~4kpc

softening

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Previous X-ray study (XMM-Newton)

PSR J1826-1334 (B1823-13) Photon index ~ 2.3 NH~1.4×1022/cm2 LX~3×1033 erg s-1 1arcmin~1pc@4kpc Pulsar

PWN

XMM-Newton 0.5-10keV

H.E.S.S TeV γ excess map

Gaensler et al. 2003 Why is the X-ray image much smaller? More extended if observed with high sensitivity? Suzaku observation!

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Suzaku: Very extended PWN

XIS 3F 1-9 keV

source

6arcmin ~6pc@4kpc 2006/9 50ksec

bgd

Suzaku can detect X-rays much more extended than the XMM results.

TeV image

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1.2× (CXB+GRXE)

CXB+GRXE

Galactic Ridge X-ray Emission

CXB

Background Source

Radial profile

Unresolved Point sources X-rays are extended at least up to 15 arcmin (~15 pc)

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X-ray spectra

Region A Region B Region C Region D Γ=1.78(1.68-1.88) Γ=1.99(1.91-2.08) Γ=2.03 (1.95-2.14) Γ=2.03 (1.95-2.14) A B C D

Reg B-D: no change in photon index. electrons reach to 15pc before cooled.

=pulsar+PWN Synchrotron cooling time~1400yrs.Velectron~10000 km/s

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HESSJ1837-069

HESS image

INTEGRAL/ISGRI (Malizia et al. 2005)

1degx1deg X-rays were detected up to 300 keV by INTEGRAL

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AXJ1838.0-0655 AXJ1837.3-0652

X-ray counterparts are offset from the TeV gamma-ray peak.

TeV peak

Pulsations of 70.5 ms were recently discovered from AXJ1838 with RXTE (Gotthelf et. al. 2008).

Offset pulsar wind nebula

Anada et al. in preparation

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Summary

SNR CTB37B Efficient acceleration O HESSJ1713-381 Offset PWN 2 extended HESSJ1837-069 PWN Very extended HESSJ1825-137 ? 2 HESSJ1804-216 ? X HESSJ1616-508 ? O HESSJ1614-518 Origin X-ray

Can you construct a “Grand Unification Theory (GUT)”

• f the dark particle accelerators?