Summary of GALWORKS Results for RTBs 971110n & 971205n
-- high source density fields --

Scans taken at relatively low galactic latitudes (thus high source density) are part of the RTB nights of 971110n and 971205n. Scans 008 to 015 on 971110n had source densities that ranged from 3.7 to 4.0 (in the log, with K < 14). For 971205n, scan 062 to 0.69 and 076 to 083 had source densities that ranged from 3.3 to 3.6. The major source of contaminent to the extended source database for these scans are double and triple stars.

Nearly 1000 sources were part of the high source density scan output from GALWORKS. Each source was 'classified' by viewing the J,H and K postage stamp images, as well as the corresponding DSS (optical) stamp images and the '3-color' image generated from the JH&K images (the latter is quite powerful since it helps the user see "color" as well as increase the snr for the low surface brightness "fuzz" around galaxies). Sources were classified into the following catagories:

galaxies
stars (isolated)
double stars
triple stars (or worse)
artifacts (meteor streaks, pieces of bright stars; false background gradients)
unknowns (sources difficult to classify)

GALWORKS is 'tuned' to optimize galaxy completeness at the expense of reliability. The minimum acceptible reliability chosen to optimize completeness is about 50% for high source density fields. That is to say, we tolerate a 50% contamination of false galaxies to our extended source database in order to be >80-90% complete in galaxy detection/extraction. We will apply post-processing methods to weed out the false sources and bring the reliability up to >80%.

Star - Galaxy Discrimination Parameters

Notes:

All "scores" normalized so that the mean scores for galaxies with 12.0 < K < 13.0 (and 13 < J < 14) have a value of unity. This step helps compare different scores (e.g., "sh" and "r23" have very different normalizing factors).

galaxies == filled white circles
stars == small red triangles
doubles == large red triangles
triples == blue crosses
artifacts == red crosses
unknowns == yellow dots

• normalized "mxdn" vs. mag
  
• normalized "sh" vs. mag
  
• normalized "msh" vs. mag
  
• normalized "wsh" vs. mag
  
• normalized "r23" vs. mag
  
• normalized "r1" vs. mag
  
• normalized "vint" vs. mag
  
• normalized "flux ratio" vs. mag
  

• score movie

Extended Source Colors

• J-K color vs. mag
  
• J-K histogram, with 9 < Ks < 12.0
  
• J-K histogram, with 12.0 < Ks < 13.5
  
• J-K histogram, with 13.5 < Ks < 14.0
  

• J-H vs. H-K , with 9.0 < Ks < 12.0
  
• J-H vs. H-K , with 12.0 < Ks < 13.5
  
• J-H vs. H-K , with 13.5 < Ks < 14.0
  

  Notes: colors computed using fixed circular radius=7" apertures; galaxies are denoted by the white filled circles; double stars by the red triangles; mean colors are represented K-corrections for spirals are represented by the magenta line and triangle points -- each point is 0.1 in redshift -- and ellipticals by the grey line and square points; the main sequence (dwarf and giant branches) are shown in green.