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High angular resolution with near-infrared Adaptive Optics in the era of the Virtual Observatory

Using VObs techniques to search for AO-suitable targets. High angular resolution with near-infrared Adaptive Optics in the era of the Virtual Observatory. seeing limited. HST. M13. Jens Zuther

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High angular resolution with near-infrared Adaptive Optics in the era of the Virtual Observatory

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  1. Using VObs techniques to search for AO-suitable targets High angular resolution withnear-infrared Adaptive Opticsin the era of the Virtual Observatory seeing limited HST M13 Jens Zuther Wolfgang Voges (MPE, MPDL), Gerard Lemson (ARI, MPE), Jaiwon Kim (MPE), and Andreas Eckart (Univ. of Cologne) ALTAIR AO @ Gemini ALTAIR AO @ Gemini 1st AIDA community workshop : Multi-wavelength Astronomy and the Virtual Observatory ESAC, 1-3 Dec. 2008

  2. Overview • Astrophysical motivation & Instrumental solution: Adaptive Optics • Find suitable targets:Virtual Observatory • Summary & Outlook

  3. 1.Astrophysical motivation & Instrumental solution

  4. (Marconi & Hunt 2003) (Tremaine et al. 2002) The hosts of Active Galactic Nuclei (AGN) • Every galaxy harbors a supermassive central black hole • M●/s relation • Coeval growth of massive black holes and galaxy bulges • Starburst/AGN connection • But only 10% of the local galaxies are Seyfert-like Size, luminosity, and structure of the host galaxy can provide valuable information on the origin and fuelling of AGN.  Need high angular resolution in order to reach small linear scales, BUT limitations by atmospheric turbulence.

  5. Solution: Adaptive Optics (AO) (Courtesy Gemini Observatory)

  6. Why conduct AO-assisted near-infrared (NIR) studies? • NIR is less influenced by dust extinction by a factor of about 30, compared to visible wavelengths. • Dominance of the red stellar host against blue AGN. • Adaptive Optics feasible in the NIR, allowing for high angular resolution and separation of nucleus and host; even at higher redshifts. • Several diagnostic lines to probe star formation and nuclear activity are available.

  7. Current results from AO studies: Fuelling • VLT NACO observation of NGC 1097(Almudena Prieto et al. 2005, AJ, 130, 1472) • Gemini NIFS observation of NGC 4051(Riffel et al. 2008, MNRAS, 385, 1129)

  8. SDSS r-band Mrk 609 – SINFONI • H+K, R~1500 • z~0.034 • FWHM~270pc • Broad Paa + [SiVI] • LINER nucleus? IRAS00317 (Zuther+ 2007, A&A, 466, 451) Folie: 8

  9. 2.Find suitable targets

  10. AO conditions • isoplanatic patchq0~l6/5 • nearby star can serve as a pointsource reference(natural guide star) • Here: • target / NGS ang. separation θ ≤ 40´´ • NGS visual brightness V< 14mag

  11. Selecting AGN • Soft X-ray background has been almost completely resolved into discrete sources, dominated by type-1 AGN ( efficient selection criterion;e.g. Brandt & Hasinger 2005). • Furthermore, the impact of the strong AGN (phase) on its host galaxy is still far from being understood satisfactory (cf. Begelman 2004; Wang 2008; Schawinski et al 2006).  crossmatch SDSS and X-ray data sets (like ROSAT or XMM)

  12. The matching problem … guide star AGN … combining catalogs with different resolutions! (i) Pure positional matching (OpenSkyQuery, GAVO matcher, AstroGrid [Topcat, Stilts]). (ii) add further knowledge like spectroscopy, X/radio correlation (SDSS AGN [Anderson et al 2003], CLASS-X [McGlynn et al 2004])

  13. The AO X-ray AGN sample: VObs in a broader sense SDSS RASS FIRST … SDSS CasJobs VOTable AstroGrid UK cone search, SIA, SSA, VOSpace, VOTable, Registry OpenSkyQuery cone search, ADQL, VOTable NED web service, cone search local DB GAVO matcher Topcat IDL + Java + Python + dpuser, spectral anaylsis, image processing DS9 overlays (Zuther et al. in prep.)

  14. Sample properties • Based on SDSS DR6 & RASS • Use Princeton spectroscopic re-reductions (97149 objects classified as AGN) • Find targets with nearby guide stars(7123) • Crossmatch AO-suitable targets with RASS(~6 optical counterparts per X-ray source)

  15. Pragmatics • Interested only in spectroscopic sources  try to validate association. • >90% of the X-ray sources have only 1 spectroscopic counterpart. • Apply the angular separation cut of Parejko et al. (Parejko+ 2008) ~550

  16. Catalogs • visualize relations betweencatalog properties

  17. Morphological classification • Large fraction point-like petrorad_r > 2‘‘ early-type

  18. BUDDA as VObs service: Work in progress (cf Gadotti 2008)

  19. Spectra Ha use Bruzual & Charlot starburst templates extracted via AstroGrid

  20. Baldwin-Phillips-Terlevich diagram composites

  21. 3.Outlook

  22. Current sample • High angular resolution is necessary, but • The sample awaits more in-depth classification(e.g., BUDDA)  focus on sizable subsets (e.g. composites) • Publication of the sample database • Publication of the AO observations  3D standards for integral-field data (EURO-3D; cf. Chilingarian 2008)

  23. Multi-conjugate AO and the Large Binocular Telescope (LBT) (Bertram 2007) VObs task: use multiple guide stars to account for large parts of the atmosphere (image credit: Marc-Andre Besel and Wiphu Rujopakarn)

  24. The end. Thanks!

  25. The need for high angular resolution • The apparent interplay between the AGN and its immediate surroundings call for high angular resolution in order to • to resolve the nuclear gas/stellar dynamics • distinguish between emission from the SMBH and the circum-nuclear environment • BUT: atmospheric turbulence limits the resolving power of large telescopes

  26. Luminosity-dependent evolution • Broad-line AGN dominate the number densities at the higher X-ray luminosities, while non broad line AGN dominate at the lower X-ray luminosities. • The comoving emissivity of AGN occurs at lower and lower redshift for AGN of lower and lower luminosity.  Downsizing (Hasinger et al. 2005, Barger et al. 2005)

  27. Throwing darts • Extensive simulation and SDSS/ROSAT cross-matching of spectroscopically identified sources give source-separation distance at fixed truematching fraction (Parejko et al. 2008)

  28. What is the VObs? • The Virtual Observatory is a framework that allows worldwide transparent access to distributed data. • Allows scientists to discover, access, analyze, and combine data from heterogeneous data collections in a user-friendly and standardized manner

  29. The AO X-ray AGN sample: Using the VObs • Cross-matching is classical VObs use case • collect catalog data (SDSS, ROSAT, FIRST, 2MASS, IRAS, …) • positional matching • collect further information, e.g., via NED

  30. What are composite galaxies? • ROSAT/IRAS match (Moran+ 1996) • Visible-l spectrum dominated by starburst features, while • X-ray spectrum typical of those of Seyfert-1s • no big-blue-bump Interpretation:AGN & star formation of similar strength • reddening towards the nucleus • host outshines AGN (e.g., Moran 2002, ApJ, 579) • cold accretion (e.g., Koratkar & Blaes, 1999, PASP,111) (cf. Moran+ 1996, ApJS, 106, 341; Panessa+ 2005, ApJ, 631, 707)

  31. The more information the better (probabilistic matching) • Pure positional matching:minimization process • OpenSkyQuery • AstroGrid & Topcat & Stilts • Add astronomical knowledge: • source type (spectroscopy) • know correlations, e.g., X-ray/radio • SDSS AGN selection (Anderson et al. 2003) • CLASSX oblique decision trees (McGlynn et al. 2004) (see Budavari & Szalay 2008 for a details)

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