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1. The glorious past of Sgr A* betrayed by molecular clouds Fe K emission. Gabriele Ponti Laboratoire AstroParticule et Cosmologie - Universite’ Paris 7 School of Astronomy and Physics - University of Southampton. R. Terrier, A. Goldwurm, A. Decourchelle, G. Belanger , G. Trap et al.
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1 The glorious past of Sgr A* betrayed by molecular clouds Fe K emission Gabriele Ponti Laboratoire AstroParticule et Cosmologie - Universite’ Paris 7 School of Astronomy and Physics - University of Southampton R. Terrier, A. Goldwurm, A. Decourchelle, G. Belanger,G. Trap et al.
Introduction: Sgr A* low luminosity - Some MC are strong neutral Fe K emitters Sgr A* flare ~ 1.51039 erg s-1 ~ 100 yr ago Sgr B2: Koyama et al. (1996); Revnivtsev et al. (2004); Terrier et al. (2009) Other MC? Sgr A variation of the MC continuum but no variation of the line Muno et al. (2007) • Low energy cosmic ray electrons Yusef-Zadeh et al. 2002; Valinia et al. (2000) • ~ 10 years (~1.2 Ms) of XMM-Newton monitoring of the 15’ region around Sgr A* • study the time variability of MC in Sgr A • disentangle the models
Fe K emission in the GC: Fe K emission concentrated in the Galactic Plane Asymmetric - stronger emission toward East Fe K emission associated with Molecular Clouds (CS)
CS emission in the GC to locate MC TMB = 2.85 K km s-1 1.31022 cm-1 TMB = 75 K km s-1 3.41023 cm-1 Where are the MC? Are all MC strong Fe K emitters? Molecular lines as tracers: MC in GC high density Uniform and complete scan of the CMZ CS Tsuobi et al. (1999) Problems: i) projection - depth in line of sight ii) MC velocity field not Newtonian BUT Coherent structures similar velocities MC selection in CS maps with velocities ranges
G0.11-0.11 Model: wabs*edge*(apec+PL+Ga+Ga) 3,8 Fe K+: E=6.408±0.002 keV, =21±7 eV, norm=7.6±0.210-5 ph cm-2 s-1 EW=790 eV; no strong 6.7 keV line nH~7.90.11022 cm-1, PL=0.79±0.05, TAPEC~1 keV, =0.520.07 4,8
Galactic plane from above Sgr A* Sgr B2 Toward the Earth G0.11-0.11 Sgr B2 NH= 81023 cm-2 Dproj= 100 pc but 130 pc in front of Sgr A* (Reid et al. 2009) Radius = 7 pc normFeK= 1.710-4 ph cm-2 s-1 L2-10 keV SgrA* ~ 1.41039 erg s-1(Revnivtsev et al. 2004) t = 100 yr G0.11-0.11 G0.11-0.11 NH=21022 cm-2(Amo-Baladron et al. 2009) Dproj=25 pc Radius=3.7 pc normFeK=0.910-4 ph cm-2 s-1 LSgrA* > 1039 erg s-1 t > 75 years Assuming FlareSgr A* = 1.41039 erg s-1 10 pc behind Sgr A* 100 yr ago
Galactic plane from above Sgr A* Sgr B2 Toward the Earth Other constraints on Sgr A* activity 50 km s-1 NH=2.71023 cm-2 Dproj=6 pc Radius=4.7 pc normFeK<1.110-5 ph cm-2 s-1 LSgrA* < 31035 erg s-1 t < 60-90 years 50 km s-1 G0.11-0.11 Coil et al. (2000)
The Molecular Arm 11,3 9,1 2,6 8,6 13,3 0,8 0,5 4 3 2 1 0,4 5 6 7
Preliminary Super-luminal motion? • Regions causally disconnected!! • No propagation of single event • Many un-correlated variations • L15pc>31037 erg s-1 - Binary in peculiar position close to arm • Flare Sgr A*
Galactic plane from above Sgr A* Sgr B2 Toward the Earth Possible past activity of Sgr A* • Arm • NH=2.71023 cm-2 • Dproj=15 pc • Radius=1.1 pc • normFeK=1.110-5 ph cm-2 s-1 • LSgrA* > 31037 erg s-1 • Assuming L=1.41039 erg s-1 • 100 pc • Sgr A* activity 500 yr Arm 50 km s-1 G0.11-0.11
Galactic plane from above Sgr A* Sgr B2 Toward the Earth Possible past activity of Sgr A* and MC distribution Arm MC1 MC2 50 km s-1 G0.11-0.11
Summary: Within 15’ from Sgr A*: + some MC with strong reflection features (Fe K line - edge - flat continuum) + some MC with no Fe K line G0.11-0.11 has Fe K line intensity, NH and position consistent with being illuminated by the same Sgr A* flare of Sgr B2 - Both light curves are decreasing - Possible end for the flare ~ 100 years ago 50 km s-1 has no Fe K line Sgr A* luminosity < 31035 erg s-1 in the last 60-90 years The arm show an apparent super-luminal motion Internal source excluded the illuminating source has to be far from the arm ( >2-4 times the apparent displacement) Sgr A* activity - best interpretation (but luminosity required is few1039 erg s-1 binary not excluded) Study of the past activity of Sgr A* Requirements: i) Deep and continuous X-ray monitoring of Sgr A and the CMZ ii) Improvements in the MC maps MC mass and position i) History of Sgr A* activity ii) Scan of the CMZ;