1. Hudson IAP July 4 Galaxy- Galaxy Lensing in CFHTLS Hudson (Waterloo) 2/3 Canadian 2/3 French

2. Hudson IAP July 4 My Last Meeting at IAP…  m/ 0.3) 0.6  8 Pike & Hudson 2005 (Pre-WMAP 3)

3. Hudson IAP July 4 CFHTLS-DEEP photo-redshifts Knowledge of the source redshifts is currently the dominant limiting factor for cosmic shear surveys. Also critical for galaxy-galaxy lensing NB: Not tested with spectroscopy in last bin (24 < i’ < 25).

4. Hudson IAP July 4 Photo-z Accuracy by Magnitude MH’s “in progress” photo-z vs. DEEP2 spectro (z< 1.4) Note that fraction of catastrophic errors doubles each mag

5. Hudson IAP July 4 Photo-z Accuracy by Magnitude works well at bright magnitudes … good for lenses in g-g lensing fraction outside 0.15*(1+z)

6. Hudson IAP July 4 Photo-z Accuracy by Magnitude … not as well at faint magnitudes … S/N or increase in blue gals with featureless spectra fraction outside 0.15*(1+z)

7. Hudson IAP July 4 Photo-z Accuracy by Magnitude … but at least the code’s error estimates are OK. 95% err

8. Hudson IAP July 4 Photo-z for Sources Drop objects with large errors and/or secondary peaks. Probably OK for cosmic shear which is cosmic variance limited. Characterize true z distribution as a function of slices in colour / magnitude space. via photo-z based on deeper IR or Spizter/IRAC …

9. Hudson IAP July 4 G-G lensing with photo-z HDF (Hudson, Gwyn, Dahle, Kaiser 98)

10. Hudson IAP July 4 CFHTLS-WIDE with photo-z Cast of dozens in Canada and France especially Parker (Waterloo -> ESO -> McMaster) Hoekstra (Victoria) van Waerbeke / Heymanns (UBC) Mellier / Fu / Terapix (IAP) Very, very preliminary both shear cats, photometry and photo-z Using only 14 sq deg with u*griz in WIDE Am using photo-z for lenses only No correction for dilution due to physical pairs or intrinsic alignment but at least this is not an “astro-ph” talk …

11. Hudson IAP July 4 CFHTLS-WIDE with photo-z ~200000 lenses 0.2 < z lens < 0.8 ~700000 sources 22.5 < i’ < 24.5

12. Hudson IAP July 4 CFHTLS-WIDE with photo-z Note horizontal axis in physical units 0.2 < z lens < 0.8 S/N of isothermal fit at R<300 kpc ~15 

13. Hudson IAP July 4 CFHTLS-WIDE with photo-z 0.2 < z lens < 0.8 ~10  ~5  ~10  ~7 

14. Hudson IAP July 4 CFHTLS-DEEP with photo-z c/o Laura Parker (also very preliminary!) low ~0.35 high ~0.61

15. Hudson IAP July 4 The Future Short term: end of summer ~25 sq deg WIDE + 4 sq deg DEEP with u*g’r’i’z’ WIDE allows us to parameterize as a function of colour, magnitude DEEP will give baseline for evolution of Tully-Fisher/Faber- Jackson/Mass-to-light Signal/Noise ~ at least x sqrt(2) shown here Refinements of photo-z, analysis (maximum-likelihood) Longer term: ~170 sq deg of survey enables subsamples by morphology, luminosity, stellar mass & redshift Halo masses, shapes as a function of above Large-scale bias as a function of above etc.

17. Hudson IAP July 4 Photo-z accuracy by magnitude Ilbert et al (tuned with VVDS redshifts)