1. 2005/9/28 X-ray Universe 2005 1 The electron and magnetic field energies in the east lobe of the radio galaxy Fornax A, measured with XMM-Newton. Naoki Isobe, Kazuo Makishima (RIKEN) Makoto Tashiro, Koichi Ito (Saitama-U), Naoko Iyomoto (GSFC), Hidehiro Kaneda (JAXA)

2. 2005/9/28X-ray Universe 20052 IC X-ray emission from lobes of radio galaxies 3C 452 (Isobe et al. 2001) Color : Chandra (0.3-7 keV) Contour : VLA radio image Energy densities in radio lobes The IC X-rays is discovered from Fornax A with ASCA (Kaneda et al. 1995) and ROSAT (Fiegelson et al. 1995) Croston et al. 2005 Isobe et al. 2005 Brunetti et al., Comastri et al., Grandi et al. u e > u m CMB-boosted Magnetic energy density u m [erg cm -3 ] Electron energy density u e [erg cm -3 ]

3. 2005/9/28X-ray Universe 20053 The radio galaxy Fornax A Distance : 18.6 Mpc Distance : 18.6 Mpc (Madore et al. 1999) (Madore et al. 1999) The 4 th brightest radio source in the southern hemisphere. The 4 th brightest radio source in the southern hemisphere. S 2.7 GHz = 98 ± 1.5Jy S 2.7 GHz = 98 ± 1.5Jy (Ekers 1969) (Ekers 1969) Double-lobe morphology, without any bright hot spots and jets. Double-lobe morphology, without any bright hot spots and jets. The dormant nucleus The dormant nucleus (Iyomoto et al. 1998. Kim & Fabianno 1999, Tashiro et al. in this session) (Iyomoto et al. 1998. Kim & Fabianno 1999, Tashiro et al. in this session) u e = u m ? u e = u m ? (Kaneda et al. 1995, Tashiro et al. 2001) (Kaneda et al. 1995, Tashiro et al. 2001) 20 arcmin 108 kpc 1.5 GHz VLA image (Fomalont et al. 1989) ASCA image

4. 2005/9/28X-ray Universe 20054 XMM-Newton image of Fornax A (1) A 60 ksec XMM-Newton observation of the east lobe. A 60 ksec XMM-Newton observation of the east lobe. ⇒ GTI : 30 ksec for MOS. ⇒ GTI : 30 ksec for MOS. 0 ksec for PN 0 ksec for PN (due to BGD contamination) (due to BGD contamination) All the east lobe is within the FoV. All the east lobe is within the FoV. NGC 1316 locates at the FoV edge. NGC 1316 locates at the FoV edge. 59 sources are detected. 59 sources are detected. Integrated flux of detected sources is smaller than the ASCA flux. Integrated flux of detected sources is smaller than the ASCA flux. MOS image in 0.3 – 10 keV 10 arcmin 54.1 kpc ⇒ diffuse emission NGC 1316

5. 2005/9/28X-ray Universe 20055 XMM-Newton image of Fornax A (2) The diffuse X-ray emission from the east lobe is confirmed. The diffuse X-ray emission from the east lobe is confirmed. Diffuse X-ray emission is also detected, between the lobe and host galaxy. Diffuse X-ray emission is also detected, between the lobe and host galaxy. MOS image in 0.3 – 10 keV  BGD-subtracted (Read & Ponman 2003)  Source-removed,  Exposure corrected  1 arcmin smoothing

6. 2005/9/28X-ray Universe 20056 X-ray Spectrum outside of the lobe Thermal emission Thermal emission kT = 0.77 +0.07 -0.12 keV kT = 0.77 +0.07 -0.12 keV (A = 0.3 A solar fix) (A = 0.3 A solar fix) Consistent with the ASCA result Consistent with the ASCA result kT = 0.77 +0.03 -0.04 keV kT = 0.77 +0.03 -0.04 keV A = 0.11 +0.06 -0.04 A = 0.11 +0.06 -0.04 (Iyomoto el al. 1998). (Iyomoto el al. 1998). r = 2.5 arcmin (13.5 kpc)

7. 2005/9/28X-ray Universe 20057 X-ray spectrum of the east lobe Power-low model. Power-low model. S 1keV = 86 +19 -9 nJy S 1keV = 86 +19 -9 nJy  X = 0.62 +0.24 -0.16  X = 0.62 +0.24 -0.16 Consistent with the ASCA result. Consistent with the ASCA result. S 1keV = 110±50 nJy S 1keV = 110±50 nJy  X = 0.7±0.9  X = 0.7±0.9 (Kaneda et al. 1995) (Kaneda et al. 1995) Slightly harder than the synchrotron radio spectrum. Slightly harder than the synchrotron radio spectrum.  R = 0.9 ± 0.2  R = 0.9 ± 0.2 (Kaneda et al. 1995) (Kaneda et al. 1995) r = 10 arcmin (54.1 kpc)

8. 2005/9/28X-ray Universe 20058 Spectral Energy Distribution 29.9 MHz 100 MHz : Finlay & Jones (1973) 408 MHz : Robertoson (1973) 843 MHz : Jones & McAdam (1992) 1.4 GHz : Ekers et al (1983) 2.7 GHz : Ekers (1969) 5.0 GHz : Kuhr et al. (1981) Total East Lobe West Lobe(ASCA) X-ray : East lobe S 1keV = 86 +19 -9 nJy  X = 0.62 +0.24 -0.16 Radio : total S 1.4GHz = 44 Jy  R = 0.68 ± 0.05  R =  X IC X-rays from synchrotron electrons

9. 2005/9/28X-ray Universe 20059 Energetics in the lobes (1) Radius S 1.4GHz  R  1keV S 1keV 10 arcmin (54.1 kpc) 44 Jy 0.68 ± 0.05 0.62 90 +8 -9 nJy East Lobe (XMM-Newton) West Lobe (ASCA, Tashiro et al. 2001 ) 7.3 arcmin (Integration region) 50 Jy 0.68 ± 0.05 0.74 ± 0.26 100 ±10 nJy B eq B IC u m u e u e /u m 1.55 1.23 +0.08 -0.06 0.60 +0.08 -0.06 3.0 ± 0.3 5.0 +1.1 -1.0  G 10 -13 erg cm -3 1.59 1.22 ± 0.07 0.59 +0.08 -0.06 2.6 +0.3 -0.2 4.4 +1.1 -0.9 Electron spectrum ∝  2  +1 ∝ ue um∝ ue um ∝ u e u CMB (Harris and Grindlay 1979)

10. 2005/9/28X-ray Universe 200510 Energetics in the lobes (2) Fornax A East lobe

11. 2005/9/28X-ray Universe 200511 Summary XMM-Newton confirmation of the IC X-ray emission from the east lobe of Fornax A. XMM-Newton confirmation of the IC X-ray emission from the east lobe of Fornax A. S 1keV = 86 +19 -9 nJy,  X = 0.62 +0.24 -0.16 S 1keV = 86 +19 -9 nJy,  X = 0.62 +0.24 -0.16 Evaluation of electron and magnetic energy density. Evaluation of electron and magnetic energy density. u e = (3.0 ± 0.3) x 10 -13 erg cm -3 u e = (3.0 ± 0.3) x 10 -13 erg cm -3 u m = 0.60 +0.08 -0.06 x 10 -14 erg cm -3 u m = 0.60 +0.08 -0.06 x 10 -14 erg cm -3 Moderate electron dominance, even though the nucleus is dormant. Moderate electron dominance, even though the nucleus is dormant. u e /u m ～ 5 u e /u m ～ 5 The u e will evolve to the equipartition value in ～ Gyr (IC + Synchrotron cooling time scale ～ 2 x 10 8 yr x (    -2. The u e will evolve to the equipartition value in ～ Gyr (IC + Synchrotron cooling time scale ～ 2 x 10 8 yr x (    -2. The IC X-ray and synchrotron radio distribution seems different The IC X-ray and synchrotron radio distribution seems different