The gas and dust contents of the young sources in the CORALZ sample A progress report

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1 The gas and dust contents of the young sources in the CORALZ sample A progress report Karl-Heinz Mack IRA-INAF Bologna Ignas Snellen Sterrewacht Leiden Richard Schilizzi International SKA Project Office, Dwingeloo Nathan de Vries Sterrewacht Leiden Hans-Rainer Klöckner University of Oxford Rene Vermeulen ASTRON, Dwingeloo

2 Sample selection point-like sources in FIRST with S peak > 100 mjy Bias against most compact sources checked with 8.4 GHz (CLASS) 30º < δ < 57.5º, b > 30º Identified with extended sources of R < 16.5 m and B < 19.5 m within 10 (APM) 17 sources, 95% complete at < z < 0.16 (CORALZ core sample): 15 GPS, 2 CSS Additional 7 sources with similar characteristics at z < (extended CORALZ sample): 5 GPS, 2 CSS

3 Spectral Ageing Analysis ν br Fit of synchrotron loss models to radio spectrum Break frequency ν br τ syn B 2 B + B 2 IC (1 + 1 z) ν br strong CSS (Fanti et al. 1995): τ syn = yr Expansion velocity: 0.34c (Murgia et al. 1999) CI: Continuous Injection (Pacholczyk 1970) JP: Pure loss model (Jaffe & Perola 1973) Dynamic ages: c (e.g. Polatidis & Conway 2003)

4 Spectral Ageing Analysis J : CSS: B eq = 140 µg; t rad < y J : GPS: B eq = 2974 µg; t rad < 7415 y

5 Expansion Velocities Ages: yr (3σ upper limits) Expansion velocities < 0.05c Similar to more powerful, but more extended radio galaxies (Scheuer 1995) Smaller than for high-power CSS/GPS Dynamic ages and velocities: N. de Vries talk

6 The structure of young AGN AGN in compact radio sources: higher gas and dust contents radio continuum emission `illuminates the Interstellar Medium Radio morphology dust emission CO emission HI absorption Megamasers Optical spectroscopy

7 Dust in young radio galaxies Frustration scenario: dense ISM absorbs and transforms radio emission to FIR no indication for the frustrated-source model from IRAS, ISO, Spitzer (e.g. Hes et al. 1995, Fanti et al. 2000, Shi et al. 2005) Fanti et al. (2000): 6/17 CSS sources with ISO detection 5/16 comparison sample for 0.2 > z > 0.8 Frustration limit: dust masses > M within 10 kpc radius at T > 30 K and assuming no contribution to a dusty disk/torus

8 Dust emission in CORALZ Pico Veleta MAMBO (250 GHz) in course to disentangle synchrotron and dust contribution: 14/17 observed: 9/17 sources with 250-GHz excess (>3σ) above estimate from synchrotron radiation

9 Dust emission in CORALZ J : GPS J : CSS

10 Additional: 7/17 with CO(1-0) detection (2 also with IRAS detection) >13/17 (>77 %) sources with good probability to host cold K.-H. Mack Riccione, 28 May 2008 Dust emission in CORALZ Pico Veleta MAMBO (250 GHz) in course to disentangle synchrotron and dust contribution: 13/17 observed: 9/13 sources with 250-GHz excess (>3σ) above estimate from synchrotron radiation additional synchrotron component? VLA (43 GHz), SCUBA

11 Dust emission in CORALZ 25 K lower limit for CSS Most CORALZ sources are GPS dust concentrated on smaller volume Higher temperature (e.g. 50 K) Lower masses Not enough for frustration scenario

12 CO emission in young radio galaxies Indicator of molecular gas contents Few systematic studies so far; some sources observed as part of other samples Mirabel et al. (1989): 4C12.50 (z=0.122) Molecular mass: M O Dea et al. (1994, 2005): search in four GPS with 0.06 < z < 0.23 Upper limits [ M, M ] García-Burillo et al. (2007): 4C31.04 (HCO+, CO(2-1)) at z = 0.06 Molecular disk (0.5-5) M

13 Pico Veleta: 115 GHz Ongoing programme 15/17 sources observed 230 GHz Simultaneously done 5(7?)/15 detections, 3 more candidates New observations scheduled CO emission in CORALZ

14 CO emission in CORALZ Dust and CO detections: 4 sources in common Galactic G/D: 100 (Spitzer 1978) IRAS sources G/D: > 500 (Downes et al. 1992) Dust might be warmer 100 K Galactic G/D

15 16/17 observed with WSRT 6/16 detected: ~ 40% Vermeulen et al. (2003): CSS: 35%, GPS: 50% Pihlström (2001): CSS: 33%, GPS: 20% CORALZ column densities: cm cm -2 VLBI mapping of first two sources under analysis. HI absorption

16 Conclusion First statistically complete sample of young sources at z<0.16 Selection only based on compactness and vicinity Number of nearby young sources increased by a factor 3 Follow-up programmes: spectral/dynamic ageing: yr, v exp < 0.05c dust content: detection > 75%; M dust 10 9 M CO(1-0): detection 40%; M mol 10 9 M HI absorption: detection 40% Megamasers: H 2 0, OH Optical spectroscopy: 2D-spectroscopy (IFU)

Proper motion and apparent contraction in the J

Mem. S.A.It. Vol. 82, 51 c SAIt 2011 Memorie della Proper motion and apparent contraction in the CSO J0650+6001 M. Orienti 1,2 and D. Dallacasa 1,2 1 Dipartimento di Astronomia Università di Bologna, Via