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Structures in the Universe, Venice March 28, 2006 David Schade Canadian Astronomy Data Centre Herzberg Institute of Astrophysics National Research Council.

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Presentation on theme: "Structures in the Universe, Venice March 28, 2006 David Schade Canadian Astronomy Data Centre Herzberg Institute of Astrophysics National Research Council."— Presentation transcript:

1 Structures in the Universe, Venice March 28, 2006 David Schade Canadian Astronomy Data Centre Herzberg Institute of Astrophysics National Research Council Canada Collaborators: –Anudeep Kanwar (poster at this meeting) –Amelie Saintonge –Luc Simard –Stephen Gwyn –Felipe Barrientos –Howard Yee –Erica Ellingson –Ray Carlberg CFHT Legacy Survey: Evolution of disk galaxies 0< z < 1

2 Structures in the Universe, Venice March 28, 2006 First detection of evolution of properties of disk galaxies: 1995, 1996 It is curious that the past decade of work has left us without a clear consensus Surface brightness evolution of disks on 0< z < 1? Schade et al. (1996): B ~1.6 mag relative to Freeman value (small disks HST & CFHT) Lilly et al. (1999): B ~ mag large disks HST Simard et al. (1998): B ~0 HST Roche et al. (1998): B ~ mag HST Bouwens & Silk (2002) B ~1.5 mag Ravindranath et al 2004: B < 0.4 M V < HST, Sersic n < 2 Barden et al. (2005): v ~ 1.0 mag HST & GEMS & Sersic M V < -20 Kanwar et al. 2006: B = M B < HST Evolution of disk galaxies

3 Structures in the Universe, Venice March 28, 2006 Disks in the Canada-France Redshift Survey Redshift > 0.5 Redshift < 0.5 Schade et al. 1995,1996

4 Structures in the Universe, Venice March 28, 2006 Disks in the Canada-France Redshift Survey Redshift > 0.5 Mean surface brightness 1.6 mag brighter than Freeman value Redshift < 0.5 Schade et al. 1996

5 Structures in the Universe, Venice March 28, 2006 The size-function of disks Luminous disks: (MB < -20) At z > 0.5 there is a large excess of small (h~2-3 kpc) disks compared to low redshift Disks in the Canada-France Redshift Survey

6 Structures in the Universe, Venice March 28, 2006 The size-function of disks Luminous disks: (MB < -20) If you reach 1.5 magnitudes fainter into the disk popuation at z < 0.5 then you find the appropriate volume density of small disks That is: Luminosity evolution (of ~1.5 magnitudes) reconciles the low and high-redshift disk populations Disks in the Canada-France Redshift Survey

7 Structures in the Universe, Venice March 28, 2006 First detection of evolution of properties of disk galaxies: 1995, 1996 It is curious that the past decade of work has left us without a clear consensus Surface brightness evolution of disks on 0< z < 1? Schade et al. (1996): B ~1.6 mag relative to Freeman value (small disks HST & CFHT) Lilly et al. (1999): B ~ mag large disks HST Simard et al. (1998): B ~0 HST Roche et al. (1998): B ~ mag HST Bouwens & Silk (2002) B ~1.5 mag Ravindranath et al 2004: B < 0.4 M V < HST, Sersic n < 2 Barden et al. (2005): v ~ 1.0 mag HST & GEMS & Sersic M V < -20 Kanwar et al. 2006: B = M B < HST Evolution of disk galaxies

8 Structures in the Universe, Venice March 28, 2006 Saintonge, Schade, Yee, Ellingson, Carlberg 2005 Disk detection and measurement completeness corrections Add simulated galaxies to real frames Recover using sExtractor Measure using fitting routine Clusters: HST Imaging of 4 clusters

9 Structures in the Universe, Venice March 28, 2006 Saintonge, Schade, Yee, etc Issues: Completeness Field galaxy contamination Mass normalization Clusters:Clusters: In these clusters there is an excess of small high-surface brightness disks at high redshift that persists after completeness and field contamination corrections are applied

10 Structures in the Universe, Venice March 28, 2006 Saintonge, Schade, Yee, etc Issues: Completeness Field galaxy contamination Mass normalization Clusters:Clusters: In these clusters there is an excess of small high-surface brightness disks at high redshift that persists after completeness and field contamination corrections are applied

11 Structures in the Universe, Venice March 28, 2006 Mass Normalization Cluster size Cluster mass Observational sampling Integrate mass model over the lines of sight Clusters:Clusters: In these clusters there is an excess of small high-surface brightness disks at high redshift that persists after completeness and field contamination corrections are applied

12 Structures in the Universe, Venice March 28, 2006 Saintonge, Schade, Yee, etc Issues: Completeness Field galaxy contamination Mass normalization Clusters:Clusters: In these clusters there is an excess of small high-surface brightness disks at high redshift that persists after completeness and field contamination corrections are applied

13 Structures in the Universe, Venice March 28, 2006 MS1054 at z=0.82 compared to evolved local sample

14 Structures in the Universe, Venice March 28, 2006 Canada-France-Hawaii Telescope Legacy Survey CFHT Megacam 36 CCDs 1 square degree field Deep Fields D1 and D3 (Kanwar et al 2006) Morphology, Photometric redshifts (Gwyn) for ~500,000 galaxies to i ~ 26

15 Structures in the Universe, Venice March 28, 2006 Disk Galaxies > 23,000 galaxies I(AB) < 24.5 B/T < 0.2 MB < Region of high completeness at z=0.9 plotted on all redshift plots Kanwar et al Completeness at z =0.9

16 Structures in the Universe, Venice March 28, 2006 Disk Galaxies 23,000 disk galaxies I(AB) < 24.5 B/T < 0.2 MB < Emerging population of small disk galaxies Galaxies in the Canada-France-Hawaii Telescope Legacy Survey Completeness at z =0.9

17 Structures in the Universe, Venice March 28, 2006 Size Function Disk Galaxies 23,000 disk galaxies I(AB) < 24.5 B/T < 0.2 MB < This rules out the no evolution model at high confidence level Factor 2-4x fewer disks at low redshift to a fixed luminosity limit

18 Structures in the Universe, Venice March 28, 2006 Evolved size function function Evolved Disk Galaxies 23,000 disk galaxies I(AB) < 24.5 B/T < 0.2 MB < Evolution of 1.5 mag in luminosity (surface brightness) from z=0.9 to z=0.3

19 Structures in the Universe, Venice March 28, 2006 Galaxies in the Canada-France-Hawaii Telescope Legacy Survey Disk Galaxies 23,000 disk galaxies I(AB) < 24.5 B/T < 0.2 MB < Luminosity evolution of 1.5 mag is sufficient to bring the size functions into agreement

20 Structures in the Universe, Venice March 28, 2006 Galaxies in the Canada-France-Hawaii Telescope Legacy Survey Disk Galaxies 23,000 galaxies I(AB) < 24.5 B/T < 0.2 MB <-18.75

21 Structures in the Universe, Venice March 28, 2006 Galaxies in the Canada-France-Hawaii Telescope Legacy Survey What is the reason for the lack of consensus? Sersic versus bulge-plus-disk models? Different selections of the population? Different luminosity ranges? Different galaxy size ranges? Are the observations fundamentally in conflict with one another? We are dealing with a censored distribution of surface brightness. Interpretations are different.

22 Structures in the Universe, Venice March 28, 2006 Evolution of disk galaxies Conclusions from CFHT Legacy Survey data: The no-evolution model for the disk size function is rejected A simple model with uniform evolution of surface brightness with redshift is sufficient to represent the observations

23 Structures in the Universe, Venice March 28, 2006 Massive galaxies in the CFHT Legacy Survey Barrientos, Schade, Kanwar: Examine the variance in the properties of the most massive galaxies in order to estimate the variance in their formation histories relative to less massive galaxies

24 Structures in the Universe, Venice March 28, 2006 Most luminous (MB) galaxies Galaxies in the Canada-France-Hawaii Legacy Survey

25 Structures in the Universe, Venice March 28, 2006 Galaxies in the Canada-France-Hawaii Legacy Survey The most luminous galaxies at z=0.9 have a distribution of types where late-type galaxies are over-represented relative to the population at the same volume density at z=0.3. There is evolution that is differential with respect to morphology even in the most luminous (massive?) galaxies.

26 Structures in the Universe, Venice March 28, 2006 David Schade Canadian Astronomy Data Centre Herzberg Institute of Astrophysics National Research Council Canada Collaborators: –Anudeep Kanwar –Amelie Saintonge –Luc Simard –Stephen Gwyn –Felipe Barrientos –Howard Yee –Erica Ellingson –Ray Carlberg CFHT Legacy Survey: Evolution of disk galaxies 0< z < 1


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