NEP Standards

NEP Standard Star Measurements with WPHot

WPHOT - IRAC photometric measurements of NEP standard stars. Three sets are shown: WPRO, WAPP and WAPPco. The "truth" value is derived from coadd measurements (using IRAF's PHOT task) and the standard IRAC aperture (R=12.22 arcseconds) and background annulus (14.4 to 24.4 arcsec).

June 22, 2009

IRAC-1

IRAC-2

IRAC-3

IRAC-4

MIPS24

IRAC-1

|   ra    |    dec  | IRAC-1| magsig| WAPPco| magsig|  diff |  WPRO | magsig|  diff |
 269.49365  66.87476  10.842   0.020  10.832   0.006  -0.010  10.826   0.006  -0.016 
 269.70920  66.82784  10.303   0.015  10.296   0.006  -0.007  10.306   0.006   0.003 
 269.65829  66.78106  11.085   0.022  11.078   0.006  -0.007  11.094   0.006   0.009 
 269.80072  66.69332   8.895   0.008   8.894   0.006  -0.001   8.906   0.006   0.011 
 270.50720  66.62753   8.965   0.008   8.964   0.006  -0.001   8.985   0.005   0.020 
 270.84106  66.56905  10.220   0.015  10.213   0.006  -0.007  10.221   0.006   0.001 
 270.79010  66.46991   7.900   0.005   7.899   0.005  -0.001   7.760   0.004  -0.140 
 269.46597  66.42963   8.268   0.006   8.286   0.006   0.018   8.154   0.004  -0.114 
 269.43304  66.44861   9.846   0.012   9.857   0.006   0.011   9.866   0.006   0.020 
 269.46442  66.51752   9.026   0.009   9.027   0.006   0.001   9.044   0.005   0.018

IRAC-2

|   ra    |    dec  | IRAC-1| magsig| WAPPco| magsig|  diff |  WPRO | magsig|  diff |
 269.49365  66.87476  10.872   0.025  10.868   0.006  -0.004  10.879   0.006   0.007 
 269.70920  66.82784  10.383   0.020  10.378   0.006  -0.005  10.388   0.005   0.005 
 269.65829  66.78106  11.170   0.029  11.164   0.006  -0.006  11.177   0.005   0.007 
 269.80072  66.69332   8.889   0.010   8.882   0.006  -0.007   8.866   0.005  -0.023 
 270.50720  66.62753   8.916   0.010   8.913   0.006  -0.003   8.923   0.005   0.007 
 270.84106  66.56905  10.307   0.019  10.305   0.006  -0.002  10.318   0.005   0.011 
 270.79010  66.46991   7.792   0.006   7.792   0.006   0.000   7.714   0.004  -0.078 
 269.46597  66.42963   8.057   0.007   8.060   0.006   0.003   8.149   0.005   0.092 
 269.43304  66.44861   9.924   0.016   9.946   0.006   0.022   9.955   0.006   0.031 
 269.46442  66.51752   9.006   0.011   9.003   0.006  -0.003   9.006   0.005   0.000 
 269.76648  66.51646  10.123   0.018  10.119   0.006  -0.004  10.131   0.005   0.008 
 270.36035  66.58640   9.272   0.012   9.268   0.006  -0.004   9.179   0.005  -0.093

IRAC-3

|   ra    |    dec  | IRAC-1| magsig| WAPPco| magsig|  diff |  WPRO | magsig|  diff |
 269.49365  66.87476  10.852   0.031  10.854   0.007   0.002  10.851   0.003  -0.001 
 269.70920  66.82784  10.334   0.024  10.339   0.006   0.005  10.341   0.003   0.007 
 269.65829  66.78106  11.133   0.035  11.121   0.007  -0.012  11.127   0.003  -0.006 
 269.80072  66.69332   8.781   0.012   8.782   0.006   0.001   8.793   0.003   0.012 
 270.50720  66.62753   8.862   0.012   8.856   0.006  -0.006   8.858   0.003  -0.004 
 270.84106  66.56905  10.250   0.024  10.246   0.006  -0.004  10.247   0.003  -0.003 
 270.79010  66.46991   7.472   0.007   7.478   0.006   0.006   7.506   0.003   0.034 
 269.46597  66.42963   7.870   0.008   7.872   0.006   0.002   7.904   0.003   0.034 
 269.43304  66.44861   9.866   0.020   9.884   0.006   0.018   9.897   0.003   0.031 
 269.46442  66.51752   8.951   0.013   8.945   0.006  -0.006   8.952   0.003   0.001 
 269.76648  66.51646  10.037   0.021  10.028   0.006  -0.009  10.038   0.003   0.001 
 270.36035  66.58640   9.237   0.015   9.232   0.006  -0.005   9.235   0.003  -0.002

IRAC-4

|   ra    |    dec  | IRAC-1| magsig| WAPPco| magsig|  diff |  WPRO | magsig|  diff |
 269.49365  66.87476  10.941   0.043  10.914   0.007  -0.027  10.920   0.002  -0.021
 269.70920  66.82784  10.287   0.032  10.311   0.006   0.024  10.336   0.002   0.049 
 269.65829  66.78106  11.035   0.045  11.036   0.007   0.001  11.082   0.002   0.047 
 269.80072  66.69332   8.834   0.016   8.833   0.006  -0.001   8.837   0.002   0.003 
 270.50720  66.62753   8.854   0.017   8.850   0.006  -0.004   8.857   0.002   0.003 
 270.84106  66.56905  10.236   0.031  10.231   0.006  -0.005  10.236   0.002   0.000 
 270.79010  66.46991   7.487   0.009   7.486   0.006  -0.001   7.497   0.002   0.010 
 269.46597  66.42963   7.982   0.011   7.979   0.006  -0.003   7.975   0.002  -0.007 
 269.43304  66.44861   9.857   0.026   9.876   0.006   0.019   9.894   0.002   0.037 
 269.46442  66.51752   8.929   0.017   8.922   0.006  -0.007   8.921   0.002  -0.008 
 269.76648  66.51646  10.033   0.029  10.028   0.006  -0.005  10.058   0.002   0.025 
 270.36035  66.58640   9.260   0.020   9.250   0.006  -0.010   9.250   0.003  -0.010

June 6, 2009

PSF: 1x1, derived from the high-fidelity IRAC-IST PRFs; PSFuncs come from the values derived by KAM using coadds, adapted by Jarrett for frames

IRAC-1

IRAC-2

IRAC-3

IRAC-4

Note: WPRO has been offset to match the aperture photometry:

-0.04, -0.05, -0.05, -0.08, 0.0 mag, respectively

May 3, 2009

Results:

WAPPco is the most accurate measure, agreeing to within 1% of the PHOT standard aperture measures. WAPP is the next with agreement 2 to 3%, and WPRO is worst measure of the bright calibrator stars with 4 to 5% accuracy. The severe undersampling of IRAC-1 and IRAC-2 is adversely affecting the WPRO measurements.

IRAC-1

IRAC-2

IRAC-3

IRAC-4

IRAC-1

|   ra    |    dec  |IRAC-1 |  dmag | WAPPco|  dmag |  diff |  WPRO |  dmag |  diff | 
 269.49356  66.87475  10.842   0.020  10.833   0.007  -0.009  10.864   0.074   0.022  
 269.70914  66.82784  10.303   0.015  10.296   0.006  -0.007  10.333   0.075   0.030 
 269.65823  66.78106  11.085   0.022  11.079   0.006  -0.006  11.100   0.075   0.015 
 269.80069  66.69335   8.895   0.008   8.895   0.006   0.000   8.901   0.078   0.006 
 270.50717  66.62755   8.965   0.008   8.965   0.006   0.000   9.078   0.088   0.113 
 270.84103  66.56905  10.220   0.015  10.214   0.006  -0.006  10.236   0.080   0.016 
 270.79007  66.46992   7.900   0.005   7.900   0.006   0.000   7.620   0.157  -0.280 
 269.46591  66.42966   8.268   0.006   8.286   0.006   0.018   8.281   0.117   0.013 
 269.43301  66.44862   9.846   0.012   9.858   0.006   0.012   9.801   0.060  -0.045 
 269.46432  66.51753   9.026   0.009   9.027   0.006   0.001   9.159   0.082   0.133 
 269.76645  66.51644  10.013   0.013  10.010   0.006  -0.003  10.046   0.057   0.033 
 270.36035  66.58640   9.370   0.010   9.366   0.006  -0.004   9.465   0.059   0.095

IRAC-2

|   ra    |    dec  |IRAC-2 |  dmag | WAPPco|  dmag |  diff |  WPRO |  dmag |  diff | 
 269.49356  66.87475  10.872   0.025  10.870   0.006  -0.002  10.927   0.041   0.055 
 269.70914  66.82784  10.383   0.020  10.380   0.006  -0.003  10.382   0.037  -0.001 
 269.65823  66.78106  11.170   0.029  11.166   0.006  -0.004  11.184   0.039   0.014 
 269.80069  66.69335   8.889   0.010   8.884   0.006  -0.005   8.916   0.043   0.027 
 270.50717  66.62755   8.916   0.010   8.915   0.006  -0.001   8.917   0.043   0.001 
 270.84103  66.56905  10.307   0.019  10.307   0.006   0.000  10.314   0.043   0.007 
 270.79007  66.46992   7.792   0.006   7.795   0.006   0.003   7.763   0.056  -0.029 
 269.46591  66.42966   8.057   0.007   8.062   0.006   0.005   8.197   0.044   0.140 
 269.43301  66.44862   9.924   0.016   9.948   0.006   0.024   9.917   0.033  -0.007 
 269.46432  66.51753   9.006   0.011   9.005   0.006  -0.001   8.995   0.041  -0.011 
 269.76645  66.51644  10.123   0.018  10.121   0.006  -0.002  10.152   0.032   0.029 
 270.36035  66.58640   9.272   0.012   9.270   0.006  -0.002   9.232   0.033  -0.040

IRAC-3

|   ra    |    dec  |IRAC-3 |  dmag | WAPPco|  dmag |  diff |  WPRO |  dmag |  diff | 
 269.49356  66.87475  10.852   0.031  10.854   0.009   0.002  10.862   0.031   0.010 
 269.70914  66.82784  10.334   0.024  10.340   0.007   0.006  10.330   0.029  -0.004 
 269.65823  66.78106  11.133   0.035  11.122   0.009  -0.011  11.099   0.032  -0.034 
 269.80069  66.69335   8.781   0.012   8.782   0.006   0.001   8.799   0.029   0.018 
 270.50717  66.62755   8.862   0.012   8.856   0.006  -0.006   8.843   0.029  -0.019 
 270.84103  66.56905  10.250   0.024  10.246   0.007  -0.004  10.241   0.030  -0.009 
 270.79007  66.46992   7.472   0.007   7.478   0.006   0.006   7.509   0.028   0.037 
 269.46591  66.42966   7.870   0.008   7.873   0.006   0.003   7.899   0.021   0.029 
 269.43301  66.44862   9.866   0.020   9.884   0.007   0.018   9.913   0.028   0.047 
 269.46432  66.51753   8.951   0.013   8.946   0.006  -0.005   8.906   0.028  -0.045 
 269.76645  66.51644  10.037   0.021  10.028   0.007  -0.009  10.124   0.025   0.087 
 270.36035  66.58640   9.237   0.015   9.232   0.006  -0.005   9.223   0.028  -0.014

IRAC-4

|   ra    |    dec  | IRAC-4|  dmag | WAPPco|  dmag |  diff |  WPRO |  dmag |  diff | 
 269.49356  66.87475  10.941   0.043  10.916   0.011  -0.025  10.826   0.040  -0.115 
 269.70914  66.82784  10.287   0.032  10.312   0.007   0.025  10.344   0.032   0.057 
 269.65823  66.78106  11.035   0.045  11.039   0.011   0.004  11.094   0.037   0.059 
 269.80069  66.69335   8.834   0.016   8.834   0.006   0.000   8.812   0.034  -0.022 
 270.50717  66.62755   8.854   0.017   8.852   0.006  -0.002   8.887   0.034   0.033 
 270.84103  66.56905  10.236   0.031  10.233   0.007  -0.003  10.239   0.037   0.003 
 270.79007  66.46992   7.487   0.009   7.488   0.006   0.001   7.516   0.031   0.029 
 269.46591  66.42966   7.982   0.011   7.981   0.006  -0.001   8.058   0.028   0.076 
 269.43301  66.44862   9.857   0.026   9.878   0.007   0.021   9.847   0.031  -0.010 
 269.46432  66.51753   8.929   0.017   8.924   0.006  -0.005   8.945   0.033   0.016 
 269.76645  66.51644  10.033   0.029  10.030   0.007  -0.003  10.114   0.025   0.081 
 270.36035  66.58640   9.260   0.020   9.251   0.006  -0.009   9.211   0.031  -0.049

Table Notes:

ra,dec == J2000 coordinates (degrees)
IRAC-1, IRAC-2, IRAC-3, IRAC-4 == standard aperture mag w/ IRAF-PHOT
WAPPco == WAPPco(add) R=6" aperture measurement (with aperture correction)
WPRO == profile fit measurement

Last update - [3 May 2009]
T.H. Jarrett (IPAC/SSC)