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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 - PowerPoint PPT Presentation
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The HICAT Optical CatalogueHOPCAT
Marianne T. DoylePh.D. Project
Content
Input Data
Matching Process
Magnitude Calibration
Results
Candidate Dark Galaxies?
Supervisor:Michael J. Drinkwater – UQAssoc. Supervisors:Elaine Sadler – Uni SydneyJohn Ross - UQCollaborators David J. Rohde - UQMike Read – WFAU
EdinburghBaerbel Koribalski – ATNF,
EppingHIPASS Team – ATNF Parkes
& Epping, Universities of : Melbourne, Cardiff, Western Sydney Macarthur, Wales, Swinburne, Technology Sydney, New Mexico, Manchester, Colorado, Sydney, LeicesterASTRON The Netherlands,AAO Sydney,WIYN Tucson etc….......
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
Input Data
Radio-Optical Position Uncertainty
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
Matching Process ADRIC Interactive Program written by David Rohde Find optical counterpart by choosing galaxy ellipse by:
Confirming HICAT velocities with published velocitiesWithout velocity confirmation
Only galaxy in imageProximity to HICAT position Velocity width ….
Visually matched by 3 peopleMarianne DoyleMichael DrinkwaterDavid Rohde
Superimposed ellipses
Yellow for correct match
15 x 15 arcmin images to allow
for the 7 arcmin position uncertaintyCentred on
HICAT positions
Selection parameters
Original
HICAT parameters
Superimposed and listedPublished velocities
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 calibration
values
Velocity Match 44% 1882 With published velocity
Good Guesses 20% 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
ResultsAnalysis of 4315 Radio Sources - 84% identified
Log HIPASS Peak Flux Vs Optical Apparent MagnitudeObjects matched by published velocities, educated guesses without
velocity and velocity matches where multiple galaxies match.
Integrated Radio flux and Apparent Blue Magnitudes Totally
independent variables
Correlation shown
Higher the blue magnitude - Higher Radio Flux
HICAT Vs HOPCAT Position Uncertainties
Difference between Radio and Optical Positions Velocity Matched
Position difference between the synthetic point sources & the fitted position after parameterization
(Zwaan et.al 2004)
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 HIPASSJ1351-46 Vel=528 km s-1 (C638)
2 previously observed at ATCA by Bärbel KoribalskiHIPASSJ0940-42 Vel = 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
HIPASSJ1946-48
B=349.7205˚
L=-28.8053˚
Vel=7730 km s-1
Ext= 0.0402
MHI=1.3x1010Msolar
Optical matching process
CompletedHOPCAT
Use Infrared & Radio
Continuum to measure SFR
Determine local galaxy
density
ATCA 21cm high resolution observation
Feb 24-27 & March 3-9 2005
178.5 hours All helpers with
observing welcome!!!!
What’s Next
Calculate SFE &
relate to galaxy
morphology
Determine which theory contributes toward the
Morphology-density relation
HIMass
SFRSFE
Lagoon Nebula100LY across
Contains many young stars
& hot gas
Thank you for your attention
Difference between Radio and Optical Positions for Velocity Matches
Difference between Radio and Optical Positions for Good Guesses
Radio-Optical Separations
50
Radio-Optical Separations
50Difference between Radio and Optical Positions for Velocity Matches
Difference between Radio and Optical Positions for Multiple Velocity & Good Guesses Matches
HI Peaks
Optical Peak
Position
Radio-Optical Position Difference
Candidate Dark Galaxies?
Hipass NameRa(h:m:s)
Dec(d:m:s)
vel_mom(km s-1)
Sint(Jy kms-1)
l(degree)
b(degree) Extinction
Density to 10th Galaxy(Gal/deg2)
Mass HI(Msolar)
HIPASSJ1317-73 13:17:40.3 -73:09:42 5666.7 3.8 304.8596 -10.3882 0.286 0.0184 5.7E+09
HIPASSJ1946-48 19:46:05.4 -48:54:35 7730.4 4.8 349.7205 -28.8053 0.0402 2.5939 1.3E+10
HIPASSJ1351-46(HVC) 13:51:18.9 -46:58:25 528.8 3.5 313.4294 14.674 0.1436 0.0994 4.6E+07
HIPASSJ0940-42(ATCA) 09:40:16.8 -42:56:56 2268.7 4.8 269.7996 7.2958 0.4938 0.0174 1.2E+09
HIPASSJ0902-40(ATCA) 09:02:02.6 -40:06:40 1636.6 12.2 262.7154 4.2126 0.5586 0.0112 1.5E+09
HIPASSJ0643-16 06:43:59.0 -16:07:33 2797.6 8.5 226.5693 -8.8849 0.5503 0.0242 3.1E+09
HIPASSJ1638-15 16:38:02.9 -15:37:48 7457.2 8.5 2.047 20.3829 0.5096 0.1955 2.2E+10
HIPASSJ1317-73
b = 304.8596˚
l = -10.3882˚
Vel=5666 km s-1
Ext= 0.286
MHI=5.7x109Msolar
HIPASSJ0643-16
b = 226.5693˚
l = -8.8849 ˚
Vel =2797 km s-1
Ext = 0.5503
MHI=3.1x109Msolar
HIPASSJ1638-15
b = 2.047˚
l = 20.3829˚
Vel=7457 km s-1
Ext= 0.5096
MHI2.2x1010Msolar