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“Black hole spin and radioloudness in a ΛCDM universe” Claudia Lagos (PUC, Chile) Nelson Padilla (PUC, Chile) Sofía Cora (UNLP, Argentina) SOCHIAS 2008.

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Presentation on theme: "“Black hole spin and radioloudness in a ΛCDM universe” Claudia Lagos (PUC, Chile) Nelson Padilla (PUC, Chile) Sofía Cora (UNLP, Argentina) SOCHIAS 2008."— Presentation transcript:

1 “Black hole spin and radioloudness in a ΛCDM universe” Claudia Lagos (PUC, Chile) Nelson Padilla (PUC, Chile) Sofía Cora (UNLP, Argentina) SOCHIAS 2008

2 Motivation: there is no convergence to explain radio-loudness! Merloni, Heinz & Di Matteo (2003) Jet production depends only on the state of the accretion disc Dichotomy Sikora et al. (2007) L R /L opt (i) Accretion rate is not enough (ii) RL prefers ellipticals The BH spin Ellipticals

3 THE METHOD Cosmology scenario: LCDM N-body numerical simulation Determine the formation and merger trees of DM halos + Semi-analytic model of galaxy formation Treatment of the physical processes that affect the baryonic component:  Gas cooling  Star Formation  Feedback processes Lagos, Cora & Padilla (2008, MNRAS, 388,587)‏

4 Computing the BH spin Shakura & Sunyaev (1973): The α-model Papaloizou & Pringle (1983) H / R ~ 1 Dubus et al. (2001) High accretion rates L BH > L edd (Volonteri et al. 2004) Blandford (1990) Lagos, Padilla & Cora (2009a) MNRAS accepted astro-ph: 0901.0547 King et al. (2005)

5 Open questions in the model Isolated processes: (i) gas cooling (ii) disc instabilities Merger of galaxies Coherent with larger scales (model A) or random (model B)? Formation of SMBHs? Shapiro (2005)Begelman et al. (2006) We will test both possibilities

6 BHs hosted by elliptical v/s spiral galaxies Lagos, Padilla & Cora (2009a) Initial value for the BH spin Ellipticals host BHs with higher spins The warped would be observable in the random case The BH spin is ~ entirely determined by the growth history

7 Acquiring the angular momentum Lagos, Padilla & Cora (2009a) same mechanisms that produce the main BH growth  One of the main advantages in use a SAM is to follow the baryon physics and to distinguish between different phenomena in the galaxy SFH self-interacting processes

8 What about radio galaxies? accretion rate Best et al. (2007) normalized spin ~ flat relation Increase fraction with masses Increase relation Increasing relation with stellar/BH mass

9 Conclusions  The BH spin is entirely determined by the accretion history. Independent on the initial BH spin  The warp treatment do not produce important differences  The main mechanisms to spin-up BHs are self-interacting. A model with random angles chosen produce important differences on this result.  Elliptical galaxies host on average BHs with higher spin values than spiral galaxies  A way to explain the increasing relation between % of radio-loud galaxies and Stellar/BH mass is using the BH spin. Lagos, Padilla & Cora (2009): astro-ph:0901.0547

10 Spin values as a function of BH mass The effect is differenctial with mass BUT! the effect is differential with mass High mass BHs have, on average, higher spin values Lagos, Cora & Padilla (2008)‏

11 Acquiring the angular momentum  One of the main advantages in use a SAM is to follow the baryon physics and to distinguish between different phenomena in the galaxy SFH Main contribution comes from self-interacting processes! WARNING Be caution with Monte-Carlo simulations!!! Ciotti & Ostriker (2007)‏

12 The Dark Matter Simulation  In concordance with the LCDM cosmology 10 Mpc/h 4 Mpc/h Springel et al. (2005)‏  Run by Roberto González (PUC)‏  Box size 60 Mpc/h and 256 3 particles  Resolution 1 x 10 9 M o /h and M max 6 X 10 14 M o  Postprocessing code by V. Springel (MPA)‏

13 Accretion rate during gas cooling Gravitational atraction The gas reservoir environment L R /L opt Radio-loud systems  Low accretion rates Ho (2002)‏ Donahue et al. (2005)‏ Higher t cool EDDINGTON LIMIT

14 The SAG model: Starburst Processes Enough massive disk  Disk component may become unstable  Mo, Mao & White (1998)‏ Disk: Stars + Cold Gas BULGE New stars BH Galaxy fusion  ≥ 0.3 < 0.3 Major Merger: both galaxies  Minor Merger: Disk: Stars + Cold Gas CENTRAL BULGE New stars / BH Satellite Stars CENTRAL BULGE Both galaxies: Cold Gas CENTRAL BULGE New stars / BH

15 The SAG model: gas cooling processes AGN is introduced in the semi-analitic model SAG1 (Sofía Cora 2006), using prescriptions of recent works (Croton et al. 2006, Bower et al. 2006, Malbon et al. 2007)‏ Hot Gas Cold Gas AGN feedback Stars FEEDBACK SNs CC SNs IaLow- mass (Portinari et al. 1998)‏ (Marigo et al. 2001)‏(Iwamoto et al. 1999)‏ Spectro-photometric evolution  Z, IMF (Bruzual & Charlot 1993)‏

16 Going to the phenomenon... BH mass BH Spin Accretion disc Magnetic field ? L BH L Disc M BH dM dt Galaxy SFH Hopkins et al. (2006)‏ Boyle et al. (1998)‏

17 Visualiting the effect of the warp disc The effect is differenctial with mass

18 Motivation: there is no convergence to explain radio-loudness! Xu et al. (1999)‏ most of the RL are Ell or S0 Gallo, Fender & Pooley(2003)‏ Radio luminosity well correlated with X-ray flux and system activity Is possible to apply this correlation to an isolated system? e.g. central SMBH

19 The SAG model in galaxy formation/evolution Lagos, Cora & Padilla 2008 (MNRAS, 388, 587)‏ Hot Gas Cold Gas AGN feedback Stars SNs CC SNs Ia Low- mass (Portinari et al. 1998)‏ (Marigo et al. 2001)‏(Iwamoto et al. 1999)‏ Disc instabilitiesGalaxy mergers BH new stars +


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