The central 80x200 pc of M83:how many BH and how massive are they? Dottori, H. (1) Diaz, R. (2) Rodrigues, I. (1) Aguero, M. P. (3, thesis) Mast, D. (3, thesis) Mediavilla, E. (4) (1) IF- UFRGS, Brazil, (2) GEMINI-S, Chile, (3) OA-UNC, Argentina, (4) IAC, Spain
Important results to this talk (from 100s more!) Sersic & Pastoriza 1965, Nucleus with Hot Spots. Jensen et al 1981, Bulge well fitted with d’V profiles r>300pc. Telesco 1988, Central giant cloud detected at 10 microns tidal signature. Gallais 1991, J,H,K photometry and astrometry of nucleus. Meloy-Elmegreen et al 1996, mass of 27 SFR, ILR resonance?. Thatte et al 2000, Bulge fit 300pc<r<700pc hidden nucleus at center. Harris et al 2000, Age and mass for ~ 40 C-N HII regions on arc. Sakamoto et al 2004, CO Vr maps of kpc along bar with 3’’ resolution. Mast et al 2006, Confirm Thatte, propose a 2 nd hidden nucleus. Maddox et al 2006, CRS on nuclear structures ( optical nucleus too). Diaz et al 2006, 3 rd object cannibalized dwarf ? Merge in <50 Myr.
credit Credit: 2-mass site Centaurus-Hydra Group (+CentA+NGC5253+…) => strong activiy of *s formation
d’V like bulge Jensen et al 81 Thatte et al 00 HST image Harris et al 00
CIRPASS(Parry et al 2000) 3D spectroscopy in the near IR Gemini Sur 490 spectra 13.0” x 4.7”, 0.36” p/fibre CCD: Hawaii-I HgCdTe (Rockwell) Format: 1024 x 1024, píxel de 18.5 um spectral response: microns; Cutting filter 1.67 um (to avoid termal noise) Dark current: 0.3 e - /s/pix Readout noise: 20 e - rms Gain: 7.5 e - /ADU Saturation: ~80000 e - EQ: 45 % en J, 65% en H For AO: GEMINI-S Perif. Wave Front Sensor is used.
CO map Sakamoto et al 2004 Claims that there are 3E8 M sol around the optical nucleus, inside 40pc.
-Optical nucleus and -kinematical center relative position from slit spectroscopy. (Thatte et al 2000) -hidden nucleus (Mast 2006)
CIRPASS detector with respect to main features in M83 central region HST image Original: Harris et al 2001 Free version: Diaz et al 2006 Meloy Elmegreen et al. 1996
Central Body, Hidden Nucleus and putative BH masses [pc] [Km/s] [pc] [Km/s] 2 10^5 Msun 1x10^6 Msun 2x10^6 Msun BH Mass
M BH [MsxE6] M ph [M s xE6] M k [M s xE6] V [km/s] r [pc] M ph * Elmegreen et al 96 ON KC HN
Discussion: Optical nucleus+Kinematical Center Optical Nucleus “…The dynamical mass of this component ( optical nucleus ) is 3E8 M sol within 40 pc …” (Sakamoto et al. 2004). Not quite: The mass distribution is more similar to that description: Optical Nucleus+ Kinematical Center “…The two nuclei would each contain an enclosed mass of 13.2E6 Msol within 5pc. That could either be a massive star cluster or a Super Massive Dark Object…” (Thatte et al 2000). Nevertheless our observations indicate that: KC and ON might have M BH not larger than 1E6 Msol and that M83 80x200 pc central are even more complex in structures. Question: What would we see if KC were observed with the VLT?
The Hidden Nucleus Is the HN of extragalactic or galactic origin? We argue (Diaz et al 2006), that it is of extragalactic origin but…, the referee does not agrees! Nevertheless, he accepted our arguments. Let, then, be open minded and accept his arguments too. If the HN is a GMC, then it might host only intermediate (Makishima style) or low mass BH. (How many, no idea)? If it is extragalactic, then it may host a BH of the mass derived previously.
Curious fact! ON+KC+HD+30 or more HII regions will merge in Myrs!. Comment: Are we so lucky people of witnessing in our backyard such a phenomenon! To be at the right time in the right place? Is M83 in the process of transformation from SABc SABb? Does the bulge accretion occurs in quasi steady state, showing always a well behaved, d’ V like profile? Does the BH increases in jumps? …. There would be recoils of the merged BHs (Madau & Rees in this meeting). Might such a phenomenon have been occurred yet?
Let me finish here to give place to your questions.
Miscellaneous
Maddox et al 2006 AJ, # Kowan 94, Stockdale 01, Soria &Wo 02 03, Maddox 03 Yet more curious!
Radio map 6cm, Telesco 88 FIR 10mu, Telesco 88