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The H ICAT Optical Catalogue H OPCAT

The H ICAT Optical Catalogue H OPCAT. Marianne T. Doyle Ph.D. Project. Content. Supervisor : Michael J. Drinkwater – UQ Assoc. Supervisors : Elaine Sadler – Uni Sydney John Ross - UQ Collaborators David J. Rohde - UQ Mike Read – WFAU Edinburgh Baerbel Koribalski – ATNF, Epping

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The H ICAT Optical Catalogue H OPCAT

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  1. The HICAT Optical CatalogueHOPCAT Marianne T. Doyle Ph.D. Project

  2. Content Supervisor: Michael J. Drinkwater – UQ Assoc. Supervisors: Elaine Sadler – Uni Sydney John Ross - UQ Collaborators David J. Rohde - UQ Mike Read – WFAU Edinburgh Baerbel Koribalski – ATNF, Epping HIPASS Team – ATNF Parkes & Epping, Universities of : Melbourne, Cardiff, Western Sydney Macarthur, Wales, Swinburne, Technology Sydney, New Mexico, Manchester, Colorado, Sydney, Leicester ASTRON The Netherlands, AAO Sydney, WIYN Tucson etc…....... • Input Data • Matching Process • Magnitude Calibration • Results • Candidate Dark Galaxies?

  3. Radio-Optical Position Uncertainty Input Data • RADIO DATA • HIPASS Catalogue - HICAT - 4315 radio HI detected sources • Meyer et. Al 2004 (Paper I ) & Zwaan et. Al 2004 (Paper II ) • OPTICAL IMAGES • SuperCOSMOS 15’ x 15’ Images • 7’ radius Radio-Optical position uncertainty • IMAGE ANALYSIS • SExtractor Image Analysis • SuperCOSMOS data catalogue? • Ellipse segmentation problem for extended objects • SExtractor Segmentation problems? • Used 2 sets of ellipse analysis parameters

  4. Input Data • Velocities to Confirm Optical Matches • NED (NASA/IPAC Extragalactic Database) • Only optical and high resolution radio measured velocities used • 6dFGS • Non-public data as at 4th September, 2003 • Hicat sources were included in survey

  5. Matching Process • ADRIC Interactive Program written by David Rohde • Find optical counterpart by choosing galaxy ellipse by: • Confirming HICAT velocities with published velocities • Without velocity confirmation • Only galaxy in image • Proximity to HICAT position • Velocity width …. • Visually matched by 3 people • Marianne Doyle • Michael Drinkwater • David Rohde

  6. Selectionparameters Original HICAT parameters 15 x 15 arcmin images to allow for the 7 arcmin position uncertainty Centred on HICAT positions Superimposed ellipses Yellow for correct match Superimposed and listed Published velocities

  7. Magnitude Calibration • SuperCOSMOS data catalogue - Calibrated • SExtractor magnitudes - Uncalibrated • Use the relationship between the SuperCOSMOS & SExtractor magnitudes for calibration • SuperCOSMOS Plate to Plate differences/Zero-point calibration • Analysed every object of 4315 blue images • Matched Galaxies To calculate magnitude calibrationvalues

  8. ResultsAnalysis of 4315 Radio Sources - 84% identified Velocity Match44%1882 • With published velocity • Good Guesses20% 851 • But no published velocity • Velocity Multi Match 14% 634 • Compact group of galaxies with published velocity • Good Guess Multi Match 6%256 • Compact group of galaxies no velocity • No Guess 11% 476 • Several galaxies no velocities • Blank Field 5%216 • No visible galaxy

  9. Integrated Radio flux and Apparent Blue Magnitudes • Totally independent variables • Correlation shown • Higher the blue magnitude - Higher Radio Flux Log HIPASS Peak Flux Vs Optical Apparent Magnitude Objects matched by published velocities, educated guesses without velocity and velocity matches where multiple galaxies match.

  10. Position difference between the synthetic point sources & the fitted position after parameterization Difference between Radio and Optical Positions Velocity Matched (Zwaan et.al 2004) HICAT Vs HOPCAT Position Uncertainties

  11. Extinction Cut at 0.6 Candidate Dark Galaxies? • 65 Possible but 58 in crowded fields • 7 possible candidates for dark galaxies? • 1 possibly HVC with ATCA Observation by Rachel Webster • HIPASSJ1351-46Vel=528 km s-1 (C638) • 2 previously observed at ATCA by Bärbel Koribalski • HIPASSJ0940-42Vel = 2268 km s-1 (C942) • HIPASSJ0902-40 Vel = 1636 km s-1 (C781) • 4 remaining HICAT Name Velocity (km s-1) Extinction (Schlegel) HIPASSJ1946-48 7730 0.0402 HIPASSJ1317-73 5666 0.286 HIPASSJ0643-16 2797 0.5503 HIPASSJ1638-15 7457 0.5096

  12. HIPASSJ1946-48 B=349.7205˚ L=-28.8053˚ Vel=7730 km s-1 Ext= 0.0402 MHI=1.3x1010Msolar

  13. Calculate SFE & relate to galaxy morphology Use Infrared & Radio Continuum to measure SFR Determine which theory contributes toward the Morphology-density relation Determine local galaxy density What’s Next • ATCA 21cm high resolution observation • Feb 24-27 & March 3-9 2005 • 178.5 hours • All helpers with observing welcome!!!! Optical matching process Completed HOPCAT

  14. Thank you for your attention Lagoon Nebula 100LY across Contains many young stars & hot gas

  15. Difference between Radio and Optical Positions for Velocity Matches Difference between Radio and Optical Positions for Good Guesses Radio-Optical Separations 50

  16. Difference between Radio and Optical Positions for Multiple Velocity & Good Guesses Matches Difference between Radio and Optical Positions for Velocity Matches Radio-Optical Separations 50

  17. HI Peaks Optical Peak Position Radio-Optical Position Difference

  18. Candidate Dark Galaxies?

  19. HIPASSJ1317-73 b = 304.8596˚ l = -10.3882˚ Vel=5666 km s-1 Ext= 0.286 MHI=5.7x109Msolar

  20. HIPASSJ0643-16 b = 226.5693˚ l = -8.8849 ˚ Vel =2797 km s-1 Ext = 0.5503 MHI=3.1x109Msolar

  21. HIPASSJ1638-15 b = 2.047˚ l = 20.3829˚ Vel=7457 km s-1 Ext= 0.5096 MHI2.2x1010Msolar

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