Observations of HIPASS radio galaxies with 6dF

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Observations of HIPASS radio galaxies with 6dF

• Michael Drinkwater, Melbourne
• (for the multibeam working group)
• 1 The HI Parkes All-Sky Survey
• HI Mass Function vs. optical morphological type
• Star formation efficiency vs. environment
• Optical counterparts for 6dF
• 2 Gravitational Lenses in the 6dF GS

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Catalogue Properties

• HIPASS
• 21cm line neutral hydrogen
• d
• -1200 12,700 kms-1
• 13 mJy RMS
• Expect 5200 detections, cf
• ZOA 1000, BGals 1000, SC 500
• Rosenburg Schneider (2000) 265
• Spitzak Schneider (1998) 75
• Henning (1995) 37

(Kilborn 2001)
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Catalogue details

• Two algorithms to detect candidates
• Artificial sources added to measure completeness
• MultiFind (Kilborn) 4? peak flux detection
• detection in 2 adjacent velocity planes
• Hanning smooth, repeat ? 2
• TopHat (Howlett)
• cross correlate spectra with top hat filter
• repeat filter sizes 1-40 velocity channels
• Candidate lists merged
• Automatic cleaning
• reject -300
• reject lines at known interference freqs
• Interactive checking parameter fitting
• accurate velocity, widths, fluxes

HIPASSJ0607-61
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Example Detections
HIPASS J0246-30
HIPASS J1035-24
Flux Density (Jy)
Flux Density (Jy)
Velocity (km s-1)
Velocity (km s-1)
HIPASS J2232-46
HIPASS J2202-20
Flux Density (Jy)
Flux Density (Jy)
Velocity (km s-1)
Velocity (km s-1)
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Parameter Distributions
velocity (km s-1)
width (km s-1)
peak flux (Jy)
number of detections per cube
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Galaxy Distribution
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Catalogue Applications

• HI Mass Function
• (Zwaan)

• HI Column Density
• (Ryan-Weber)

• Local Groups
• (Stevens)

HIP 1723-80
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Catalogue Applications

• Tully-Fisher (Meyer)

• Correlation Function
• (Tantisrisuk)

• Inclination 500
• Sb-Sc SBb-SBc

?(r/r0)-? r0 3.55 ? 1.7
1 ?(s)
Magnitude ki20e - 5log(v/100) -25
S (h Mpc)
Rotational Velocity log(v50max)
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Catalogue Applications

• Unusual objects, eg no optical counterpart
  (Kilborn, Koribalski)

Declination (J2000)
HIP 976 (IC5332)

• Survey sample selection, eg SINGG (Meurer et. al.)

HIP J1712-64
Right Ascension (J2000)
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Catalogue Status

• Status
• Spectra on line at
• www.atnf.csiro.au/research/multibeam
• draft catalogue completed
• Papers in preparation
• I. Parkes HI Catalogue
• II. Completeness Analysis
• III. Optical properties
• 15 arcmin beam ? 4 arcmin position errors
• ? high resolution ATCA image OR optical redshift

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HI mass distribution

• Low-mass slope of HI mass function (HIMF)
• HI mass function ? optical luminosity function
• most baryonic mass in low surface brightness
  HI-detected galaxies?
• steeper slope than other studies

• HIMF as a function of optical morphology
• neutral gas ? morphology ? environment
• is morphology driven by formation conditions or
  later interactions with environment?

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Star formation efficiency

• NIR optical
• Star formation past and present
• HIPASS (HI)
• remaining fuel ? star formation future
• failed star formation

Optical H? NIR
HI total HI ?V
HI velocity

• SF efficiency as a function of environment
• density-morphology relation (Dressler 1980)
  decrease in of late-type (SF) galaxies in
  regions of high galaxy density
• test models of the density-morphology relation
  using data not biased by current star formation

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HIPASS 6dF Sample

• Aim optical identification of HIPASS
• 4 arcmin position uncertainties
• traditional solution high resolution radio
  imaging
• not realistic for 5000 sources!
• statistical solution measure redshifts for all
  possible matching galaxies then match by velocity
• 6dF not complete but should match majority
• bonus synergy with 6dF and 2MASS science

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HIPASS 6dF Sample

• Optical identification using 6dF redshifts
• optical redshifts of any possible matches
• 6dF already doing galaxies R
• HIPASS b10 deg, Dec
• matched to SuperCOSMOS galaxies N66132
• 15.6WFAU)
• automatic and manual cleaning N2710
• 4? peak flux limit (50 mJy) N1195
• additional target total N717

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• HIPASS matches SuperCOSMOS R-band 1arcmin images

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Summary of outcomes

• 1. Optical IDs (catalogue paper III)
• statistical first pass using position matches to
  SuperCOSMOS sky catalogues
• improve with colour and morphology
• 2. 6dF identifications (in 3-4 years)
• best solution using redshift matches
• detailed analysis of density-morphology relation

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2. Gravitational Lenses in the 6dF GS

• Rosetta Stone of lensing
• QSO2237050
• (Huchra et al 1985)

• lens z0.04 spiral galaxy
• model (C. Trott)
• core of dark matter profile is flat, not cuspy
• any of these in the 6dF GS?

total rotation curve
dark matter
disk
bulge
bar
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Gravitational Lenses in the 6dF GS

• Detection statistics
• galaxies magnified QSOs preferentially selected
  in flux-limited galaxy surveys
• but QSO counts drop rapidly at brighter limits
• 2dF GRS (2.5 105) ? 10 lensed galaxies
• SDSS (106) ? 100 lensed galaxies
• (Mortlock Webster 2000)
• 6dF (105) ? 1 lensed galaxies
• but 10 if QSOs as red as B-K8
• (Mortlock Drinkwater 2001)

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Gravitational Lenses in the 6dF GS

• Search of 2dF GRS
• search underway at Cambridge
• 2 good candidates not confirmed lenses
• D. Mortlock, P. Hewett D. Madgwick
• Search of 6dF GS
• same software will be used
• when 6dF data released!

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