optical photometry
Download
Skip this Video
Download Presentation
Optical photometry

Loading in 2 Seconds...

play fullscreen
1 / 15

Optical photometry - PowerPoint PPT Presentation


  • 107 Views
  • Uploaded on

Optical photometry. Coverage. CFH12K BVRI (limited area; but all patches have full filter coverage) Less stable calibration, but contiguous area Megacam ugriz (9h lacks u; 21h lacks i) Wide field, stable reduction: chip gaps. 2h coverage. B/u V/g R/r I/i/K/IRAC. 9h coverage. B/u V/g

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Optical photometry' - wes


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
coverage
Coverage
  • CFH12K
    • BVRI (limited area; but all patches have full filter coverage)
    • Less stable calibration, but contiguous area
  • Megacam
    • ugriz (9h lacks u; 21h lacks i)
    • Wide field, stable reduction: chip gaps
2h coverage
2h coverage

B/u

V/g

R/r

I/i/K/IRAC

9h coverage
9h coverage

B/u

V/g

R/r

I/i/K/IRAC

14h coverage
14h coverage

B/u

V/g

R/r

I/i/K/IRAC

21h coverage
21h coverage

B/u

V/g

R/r

I/i/K/IRAC

combining systems
Combining systems
  • R and r: Put both on SDSS system
    • Small additional correction
    • Good to within 0.05 mag
  • I and i
    • Fit small correction as function of (B-V)
    • Good to 0.05 mag
  • K (SOFI), K (INGRID)
    • Little overlap. Only good to ~0.2 mags.
  • Spitzer 3.6 to K
    • Fit [3.6]-k vs z. Then k-correct.
    • Probably good to 0.2 mags
k corrections
K-corrections
  • Blanton v4.1.4. Computed at z=0, 0.3 and 0.4.
  • Extinction correct; add some error (0.02 to 0.05) to mags
  • Checked on SDSS data

Observed (g-r)

Colour-coded according to rest-frame colour

slide11

Groups

Field

red fraction
Red fraction

Groups

Field

  • If either (g-r) or (B-V) are red
old fraction
Old fraction

Groups

Field

Old Fraction

things to do
Things to do
  • Comparison with
    • Poggianti clusters
    • z=0 groups (e.g. Weinmann)
    • Font et al. models
  • Take a closer look at individual groups.
  • Faint blue galaxies: anything unusual??
ad