Sgr B2 Galactic Center Survey with Chandr Radio Arc １ Sgr A East ： Young SNR 2 The GC Hot Plasma ： 10keV 3 Sgr B2, Radio Arc ： Molecular Clouds ~2 x 1 degrees 2 2 Sgr A East & GC Hot Plasma

Scientific Objectives A) The Dynamics of the Galactic Center 1) Galactic Rotation of the Hot Components vs Cold Matter Center energy of the 6.4 keV line & 6.7 keV resonance line Q. How different between the Molecular cloud, SNR and Diffuse plasma 2) Direct Observation of Internal motion (Doppler broadening) Radio Arc ~70 km/s, Sgr A East, Expanding Velocity ~1000 km/s Diffuse Plasma 1700 km/s (10 keV) B) Sensitive Test of the XRNe & Cloud Geometry, Parameters Compton shoulder of the 6.4 keV line from Sgr B2. Compton recoil of the 6.7 keV line (from Sgr A East) of the Radio Arc C) Diagnostic of the GC plasma (1) Iron abundances of GC Flux of the 6.4 keV, He-like Ka complex, Kb etc (2) Electron temperature 6.7 keV / satellite line complex (Sgr A East) (3) Ionization temperature 6.7 keV / Ly alpha (10 keV Plasma)

Sgr B2 and Radio Arc with the 6.4 keV line XRN Compton Shpulder & Recoil Sgr B2 and Radio Arc with the 6.4 keV line XRN Compton Shpulder & Recoil 8

Sgr B2 (100 ksec ) Compton Shoulder Peak at 6.37 keV 10 eV (error~10 eV, 10 deg), Forward Compton x Absorption is maximum in front Line Broadenning Sgr B2 70 km /s => ~1.5 eV Ka center: ～ 0.3 eV width: 1.7 eV ～ 0.3 eV Kb center: ～ 0.7 eV width: 1.3 eV (0-2.2 ） eV (90% confidence) Radio Arc (100 ksec ) Thermal + XRN model 6.4 keV line center: 0.3 eV, width: 0.5 eV 6.7 keV resonance line center: 1.2 eV, width: 1.5 eV

Non-Thermal X-Ray Filaments Sgr A* 1 2 3

Diffuse Hot Plasma ~10 keV 6.4 keV Resonance Forbidden Ly α & β

10 keV Hot Plasma 100ks 6.4 keV ( )best error center keV 1 eV width 2.7 eV keV ( )best error Center eV Width 3.2 eV keV keV ( ) best error Center eV Width1 2.8 eV Ceneter eV Width2 3.4 eV

The Galactic Center region The Galactic Center region K. Koyama and A. Senda (Kyoto-U) Y. Maeda and H. Murakami (ISAS / JAXA) Y. Maeda and H. Murakami (ISAS / JAXA)

The central region of our galaxy Various high energy activities The nearest MBH (= Sgr A*) Largely extended hot plasma – ⇒ 10 5 yrs past activity of the GC SNR / SNR candidates – ⇒ 10 4 yrs past activity of GC X-ray reflection nebulae – ⇒ 10 3 yrs past activity of GC

Target selection Target selection The GC hot plasma –plasma dynamics, galactic rotation Sgr A East –SNR dynamics, galactic rotation Sgr B2 / Radio arc –X-ray reflection nebula, Compton shoulder / recoil

GC hot plasma Neutral Iron (6.4 keV) –Trace the dynamics of the Cold Molecular cloud He/H-like Fe-K (6.7 / 6.9 keV) –Trace the dynamics of the hot plasma Molecular cloud motion maybe Dominated by Galactic Rotation ⇒ What regulates the plasma dynamics ? Galactic Rotation ? Thermal motion ? Past explosive event of Sgr A* ? ⇒ What is the relation between the dynamics of cold and hot matter ? Sgr A* Rotation curve near the GC region Sgr A East GC hot Plasma

Plasma motion On the galactic rotation curve – ⇒ V rot ～ 20 pc – ⇒ ΔE ～ 0.4 eV Thermal motion – ⇒ V th ～ 170 ⇒ σ ～ 4 eV Expanding motion centered at Sgr A* XRS 100 ks keV resonance line –ΔE = ±0.5 eV –Δσ= ±0.3 eV Galactic rotation is detectable.

Sgr A East Chandra confirmed Sgr A East is an SNR (Maeda et al. 2002). Mixed-Morphology SNR High temperature (2 keV or 1 + 4keV) High metal abundances (> 3solar) Regulate the past activity of Sgr A* ? Key science Temperature measurement line ratio 6.9/6.7 SNR dynamics Whether on the Galactic rotation curve? Chandra ACIS-I Sgr A*

Simulated spectrum XRS 100 ks simulation GC hot plasma component is excluded Si / S / Ar / Fe line Fine structures around 6.7 keV line can be resolved resonance intercombinations forbidden Li/Be-like satellites line center error ～ ±0.3 eV line width error ～ ±0.4 eV keV ～ 20 km/s galactic rotation are detectable

Sgr B2 / Radio arc Giant Morecular clouds Irradiated by The External source toward the GC. ⇒ X-ray reflection nebulae (XRN) Key Science Compton shoulder of 6.4 keV fluorescent ⇒ Prove Geometry of the Irradiation source Compton recoil of strong 6.7 keV irradiation ⇒ Prove 3D configuration of Molecular cloud and Irradiating Source (Sgr A*). Confirm the XRN model and Trace the past activity of Sgr A* x10 38 (year) Past luminosities of Sgr A * 3’

Sgr B2 XRS 100 ks simulation Compton shoulder of 6.4 keV is clearly seen. 6.4 keV neutral Kα –Line center ±0.3 eV –Width 1.68 eV(1.32 – 1.95) Compton shoulder –Energy uncetainity ～ 10 eV –Intensity ～ % ⇒ Irradiated direction are determined within 10 % keV 6.37 keV Kα Kβ Absorption edge

Radio arc Reflection (PL keV fluorescent) + Thermal component 6.4 keV ⇒ molecular cloud geometry 6.7 keV ⇒ plasma dynamics 100 ks XRS observation center width 6.4 keV ±0.3 eV ±0.5 eV 6.7 keV ±1.2 eV ±1.5 eV keV

Non-thermal emission Connection between 10keV --sub MeV band High energy activity at the GC. Integral IBIS/ISGRI 20-40keV 2deg x 2deg image of GC