The Suzaku Results of the Galactic Center X-rays - Collisinal Excitation or Charge Exchange ? - Katusji Koyama, Kyoto University

Nickname Suzaku

An AncientOriental mythology

ASTROE2 Launch:

2005/7/10

３ Main Instrumnets on Suzaku ：　 HXD, XRS, XIS

Resonance (r)6.703keV

1s2p1P1

Forbidden(f)6.639keVΔl=0,Δs=1

Fine Structure of Fe24+

1s2 1S0

1s2p3P0,1,2

Δl=1,Δs=0 1s2s 3S1Name 　　　　　　　 Transition 　　　 　 Energy (eV)---------------------------------------------------------Resonance (r) 　 1s2s １ S0-1s2p 1P1 　　 6700.5Intercombination line 　　　 (x)　　　　 1s2p1S0-1s2p 3P2 　　　 6682.4　　　 (y) 　　　　　　 1s2p1S0-1s2p 3P01 　　 6667.6Forbidden line (f) 1s2 1S0-1s2s 3S1 　 6636.7

-60 mK, 7.0 eV @5.9 keV: 　 World (Universe) Records. But !

The XRS Spectrum on Orbit

ASCA 320 ksec (Koyama et al. 1996)

Chandra 600ksec (Muno et al.2004)

XMM 50 ksec (Tanaka)

XIS: The Best Performance as an X-ray CCD

Si X

III

Kα

Si X

IV K

α

Si X

III

Kβ

S X

V K

αS

XV

I Kα

S X

V K

β

Suzaku: 　 180 ksec

Si12+Kα

Si12+Kβ

6 7 8

Fe24+Kα Fe25+K

α

Fe24+Kβ

FeKαNi26+Kα

FeKβ

Fe25+Kβ

Ni27+Kα

Ni Kα

Ar16+Kβ

Ar16+KαSi13+Kα Ca18+Kα

Ca19+KαAr17+Kα

S14+Kα

S15+Kα

S14+Kβ

Is the 6.7 keV lineCollisional Excitation or Charge Exchange ?

6.4 keV

6.7 keV

2.46 keV

He-like Fe K = 6679 eV Close to 6685eV( =6eV)Width () = 38 eV　　 (Triplet, not Velocity) Collisional Excitation

Name Observed Lab ⊿ (eV)-----------------------------S Ly 2622.4+3.6-2.7 2621.6 0.8FeLy 6969.5+2.8-2.1 6965.7 3.8Mn K 5899.6+1.7-0.4 5895.1 4.5

Collisional Excitation= 6685 eVElectron Capture = 6666eV

r

rf

f

6685eV

6666eV

FeXXV FeXXIV

i

i

G-ratio = r / (i+f)

Wargelin, Beiersdorfer et al. 2005, ApJ, 634,687

Ec= 6679 eV +/- 1 eV ( systematic error~ +- 5 eV):The G-ratio decreases as decreasing plasma temperature.　It also decreases with temperature due to the contribution of satellite line. Thus we can constrain the plasma temperature kT using the center energy. The results are: kT = 3.2 keV +3 -1 keV 　（ Vapec) kT = 7.5 keV +∞ -3 keV 　（ VMEKAL) This is just the XRS science, hence our GC study make more clear strategy for the NeXT, the corner stone project in Japan.

Ionization Temperature Fe Klike/He-like: kTi=6.5 keV +/- 0.1ke V Fe K H-like/He-like: kTi=5.1 keV + 1.5 -1.0 keV Ni K H-like/He-like : kTi= 9.3 keV +1.6 -2.5 keV Electron Temperature He-like Fe K/K : kTe=6.2 keV +3 -1keV H-like Fe K/K : kTe> 6.5 keV (lower limi ｔ )

All the results are consitent if the Plasma is kTi ~ kTe=6.5 keV.This methodology to determine the electron temperature (kTe) at the Fe energy is possible only with Suzaku. Our new method constrains the Continuum shape, hence can separate the Non-thermal components.

Temperatures are nearly Constant at l=-0.4 ～ +0.1 deg ,while decrease at the 6.4 keV Cloud

6.7 keV Flux is smooth over the GC Region

GC Background can be reliably estimated

Sgr A East

Ec=6663 (6661-6664) eV (6685 eV)Width= 47 (44-51) eV

New SNR Sgr A East

2-temperature CEI ModelkTH = 4.9 keVkTL = 1.2 keV

NEI ModelkTH = 13 keVkTL = 1.2 keVnt = 2x1010 sec

May be Multi-temperature

CEI

NEI

NEI

The West of the Radio Arc

We found not onlyneutral Fe K but also Fe K and Ni K

Fe

Ni

Neutral Fe (Fluorescence) Neutral Ni (Fluorescence)

　　 He/H-like Fe (GC-plasma: BG)

6.7 keV , 2.46 keV Line Map　　 Discovery of New SNR Candidates 　 Related to the GC plasma ? Cosmic Ray Acceleration ?

6.4 keV Line Map　　 Discovery of New XRNs 　 Past History of the Sgr A* Activity (Echo) ？ Related to the HEESS-TeV Emission ?

6.7 keV

6.4 keV

New Sources in the Sgr B & C Regions

2.46 keV

6.40keV-MaP

6.70keV-Map

30 pc

Sgr A*

The Galactic Center Observed with Suzaku

2.46keV-Map

　　　　　　　１０８ K Plasma

　 １０７ K Plasma　　　　　● 　　　　　

Black Hole

Molecular Cloud

朱雀

飛鳥時代のキトラ古墳の壁画

Suzaku

The wall painting of “Suzaku” in the ancient tomb “Kitora” built in the Asuka Era

明月記

客星出現例

一條院寛弘三年四月二日

葵酉

夜以降騎官中有大客星

Meigetsuki :Records of guest stars

In the 1-st May 1006,a large guest star appeared within the Kikan (Lupus)Constellation