From roc@ipac.caltech.edu Thu Sep 12 11:24:39 2002
Date: Wed, 11 Sep 2002 17:50:46 -0700 (PDT)
From: Roc Cutri <roc@ipac.caltech.edu>
To: Tom Jarrett <jarrett@ipac.caltech.edu>
Cc: Nian-Ming Chiu <nmc@ipac.caltech.edu>, Roc Cutri <roc@ipac.caltech.edu>
Subject: Re: provisional XSC

I did a quick query on the XSC (fp_xsc) and found 25 large galaxy
entries that have prox values <10.  this means that some number of
the things that were supposed to have been cleaned out were not.

We need to figure out what happened here.

Here is a table showing the prox values, the cntr of the "companions"
(pxcntr) within 10", the cntr of the large galaxies,

Roc


|prox|   pxcntr|     cntr|
|doub|      int|      int|
|arcs|         |         |
|null|     null|     null|
6.500   2113207   5000022
4.700   1556238   5000068
1.100   2597355   5000097
0.600   1389589   5000130
1.100    427608   5000154
0.900   1217362   5000208
0.700    433569   5000253
1.400   2476860   5000262
3.800   1559034   5000293
0.200   1753655   5000299
6.100   1024635   5000302
4.900   1211459   5000303
1.600   1148482   5000324
1.200    364639   5000325
8.200   1764061   5000361
9.400    289054   5000373
5.300   2144128   5000379
1.500    681660   5000383
0.200    724313   5000445
0.100   2275639   5000464
6.300   1584307   5000485
0.700    617601   5000504
0.900   1784478   5000505
0.800    617600   5000511
0.300    298920   5000515

From jarrett@ipac.caltech.edu Thu Sep 12 11:25:06 2002
Date: Wed, 11 Sep 2002 19:39:53 -0700
From: Tom Jarrett <jarrett@ipac.caltech.edu>
To: Roc Cutri <roc@ipac.caltech.edu>
Subject: Re: provisional XSC

Roc Cutri wrote:
> 
> I did a quick query on the XSC (fp_xsc) and found 25 large galaxy
> entries that have prox values <10.  this means that some number of
> the things that were supposed to have been cleaned out were not.
> 
> We need to figure out what happened here.
> 
> Here is a table showing the prox values, the cntr of the "companions"
> (pxcntr) within 10", the cntr of the large galaxies,
> 
> Roc

Ok, looking at the code, it is a little more complicated.
First, I do an elliptical search around the parent galaxy.
Your prox parameter is probably a circle, right?
Second, I do a 6" minimum threshold (semi-major axis), as so:

rparent = riso (the isophotal radius)
R' = 0.05 * rparent (5% of isophotal radius)
Rmin = max (R', 6")
kill R < Rmin 
(where R is the semi-major axis)

So with this algor, about half (12 or so) problem sources will
go away.  Still, the other dozen are getting through (based on
the circular proximity indicator). I don't know how this
happened.  I guess the good news is that these guys are "z" sources
so they are benign (from a photometry point of view).
-tj

From jarrett@ipac.caltech.edu Thu Sep 12 11:25:21 2002
Date: Thu, 12 Sep 2002 08:38:14 -0700 (PDT)
From: Tom Jarrett <jarrett@ipac.caltech.edu>
To: roc@sagan.ipac.caltech.edu
Subject: problem sources

looks like the large galaxy dupes are the following:
|  cntr|         ra|       dec|cc_flg|
 1389589   71.427223 -59.247250 0      
 427608   54.114891 -34.975994 0     
 433569   53.755501 -24.933279 0      
 1148482   65.861160  75.295525 0      
 364639   55.547756 -29.893326 0      
 2275639   27.628557   6.145182 0      
 298920   69.092911 -10.376227 0      
 1784478  158.132736  54.401070 0      


The other dupes are "z" sources, so they are benign.
So the above "0" represent pipeline dupes of large "Z"
galaxies.  We either delete from catalog, null photometry,
or leave them in and note their presence in the catalog.
Any option is fine with me.
-tj