SciOp

EUROPEAN SOUTHERN OBSERVATORY

La Silla Observatory

SCIENCE OPERATION DEPARTMENT


SciOp


NTT Technical Report:
Guide Probe Mapping

LSO-TRE-ESO-40200-X/X.0

Prepared O.Hainaut 2003-05-13

Revision History

0.1
2003-05-13 ohainaut

1.- INTRODUCTION

1.1- PURPOSE and SCOPE

This document lists and analizes the results of NTT Guide Probe position measurement. The analysis leads to a conversion from/to RA-Dec to/from XY.

1.2- STYLISTIC CONVENTION

1.3- ACRONYMS AND DEFINITIONS

1.4- DOCUMENTS AND REFERENCES

2.- DATA

The data were acquired by M.Billeres in March 2003. The method consists in pointing an open cluster, then to move the guide probe to several stars in the cluster, always centering the GP on the star (using the "move to ref.spot" button on the correponding GUI) without moving the telescope.

This experiment is reproduced for a rotator offset of 0 and 180deg.

Rotator = 0deg:

   RA           Dec           X     Y

   09 17 07.05 -36 39 10.69 138.2  11.5 
   09 16 59.55 -36 40 15.92 138.0  29.8 
   09 16 52.53 -36 45 37.84  77.6  41.3 
   09 16 41.82 -36 40 30.47 132.6  69.3 
   09 16 40.50 -36 43 49.19  95.5  69.5 
   09 16 32.74 -36 47 43.76  51.2  83.6 
   09 16 14.10 -36 47 02.65  55.9 125.6 
   09 16 13.48 -36 46 15.24  64.6 127.6 
   09 16 02.42 -36 46 10.13  63.7 152.4 
   09 16 00.19 -36 47 42.11  45.8 156.3 
   09 15 47.83 -36 50 08.12  17.5 181.4 
   09 15 42.56 -36 48 06.77  39.4 195.0 
   09 15 45.62 -36 47 41.31  44.4 188.5 
   09 15 34.21 -36 47 05.35  49.2 214.4 
   09 15 11.84 -36 41 07.69 111.7 269.8 
   09 15 02.07 -36 42 22.18 113.2 279.9 
   09 14 56.69 -36 43 33.20  96.4 290.3 
   09 14 57.67 -36 44 44.09  82.1 301.1 
   09 15 10.65 -36 36 35.78 161.8 275.9 

Rotator = 180deg

   09 16 56.78 -36 36 05.98  166.3 293.1
   09 15 47.40 -36 25 27.48   40.8 130.2
   09 16 13.77 -36 26 12.34   45.1 189.9
   09 16 21.00 -36 23 08.48    9.9 203.4
   09 16 29.80 -36 23 03.19    7.5 233.1
   09 15 58.90 -36 24 11.34   24.9 154.9
   09 15 49.76 -36 24 34.85   30.8 134.7
   09 15 39.71 -36 25 53.40   47.0 113.7
   09 15 31.97 -36 24 50.72   36.5  95.1
   09 15 25.51 -36 25 41.05   46.8  81.4
   09 15 30.61 -36 29 20.54   86.6  95.9
   09 15 19.61 -36 29 51.43   94.1  71.9
   09 15 14.52 -36 27 22.97   67.4  58.3
   09 15 11.76 -36 26 40.13   59.9  51.5
   09 15 14.10 -36 25 22.73   45.4  55.0
   09 15 08.25 -36 25 38.24   49.1  42.8
   09 14 55.08 -36 29 38.69   90.8  12.7
   09 14 59.97 -36 34 03.97  144.0  31.6
   09 14 50.44 -36 35 05.60  154.8   2.7
  

3- Analysis and Results

Using the POS1 package [1], the astrometric solution of the data was computed.

Rotator = 0.deg

 *- X-Transformation
   No of data =  10   No of variables =  4
     Constant term =  0.21831649E+00
     Variable      Coefficient    Variation of coefficient
     Fct( X    )   0.107430E+00     0.377032E-05   [mDeg/unit]
     Fct( Y    )  -0.152427E+01     0.130356E-05
     Fct( XY   )   0.558777E-01     0.938336E-04
   R square =       0.10000E+01
   R.A. is toward y<0
   Approx. Pos.Angle:  -85.97
   Approx. plate scale:   5487.377 miliarcsec per Pixel or Micron
   
 *- Y-Transformation
   No of data =  10   No of variables =  4
     Constant term =  0.12575173E+00
     Variable      Coefficient    Variation of coefficient
     Fct( X    )  -0.149838E+01     0.138385E-04 [mDeg/unit]
     Fct( Y    )  -0.104144E+00     0.478455E-05
     Fct( XY   )   0.268685E-02     0.344403E-03
   R square =       0.10000E+01
   Dec. is toward x<0
   Approx. Pos.Angle:    3.98
   Approx. plate scale:   5394.184 miliarcsec per Pixel or Micron
   
   
Row    No   Mag        Measured               Catalogue         Deviation
<-> <----> <--> <---RA---> <---Dec--> <---RA---> <---Dec-->  -X-arcsec-Y-
  4      4 12.0  91641.826 -351929.89  91641.821 -351929.54  0.053 -0.357
  5      5 12.0  91640.497 -3516 9.89  91640.499 -351610.81 -0.031  0.914
  6      6 12.0  91632.719 -351216.37  91632.739 -351216.24 -0.254 -0.134
  7      7 12.0  91614.109 -351257.62  91614.099 -351257.35  0.125 -0.273
  8      8 12.0  91613.510 -351345.29  91613.480 -351344.76  0.363 -0.537
  9      9 12.0  916 2.399 -351349.74  916 2.421 -351349.87 -0.267  0.121
 11     11 12.0  91547.859 -35 951.40  91547.831 -35 951.87  0.345  0.474
 13     13 12.0  91545.606 -351219.10  91545.619 -351218.69 -0.159 -0.402
 14     14 12.0  91534.194 -351254.53  91534.211 -351254.65 -0.218  0.113
 19     19 12.0  91510.653 -352324.14  91510.649 -352324.22  0.043  0.078
  RMS in X-direction (arcsec):  0.231
  RMS in Y-direction (arcsec):  0.443

Rotator = 180deg

 *- X-Transformation
   No of data =   9   No of variables =  4
     Constant term = -0.16137123E+00
     Variable      Coefficient    Variation of coefficient
     Fct( X    )  -0.136449E+00     0.308979E-05 [mDeg/unit]
     Fct( Y    )   0.149629E+01     0.606479E-06
     Fct( XY   )   0.209596E+00     0.606834E-04
   R square =       0.10000E+01
   R.A. is toward y>0
   Approx. Pos.Angle:  -84.79
   Approx. plate scale:   5386.636 miliarcsec per Pixel or Micron
   
 *- Y-Transformation
   No of data =   9   No of variables =  4
     Constant term = -0.11302590E+00
     Variable      Coefficient    Variation of coefficient
     Fct( X    )   0.156826E+01     0.230264E-04
     Fct( Y    )   0.152148E+00     0.451973E-05
     Fct( XY   )  -0.102789E+01     0.452237E-03
   R square =       0.10000E+01
   Dec. is toward x>0
   Approx. Pos.Angle:    5.54
   Approx. plate scale:   5645.743 miliarcsec per Pixel or Micron
   
   
Row    No   Mag        Measured               Catalogue         Deviation
<-> <----> <--> <---RA---> <---Dec--> <---RA---> <---Dec-->  -X-arcsec-Y-
  1      1  0.0  91656.780 -352354.01  91656.780 -352354.02  0.005  0.015
  2      2  0.0  91547.396 -353432.61  91547.400 -353432.52 -0.050 -0.090
  3      3  0.0  91613.777 -353347.37  91613.770 -353347.66  0.088  0.287
  9      9  0.0  91531.957 -3535 9.31  91531.970 -3535 9.28 -0.159 -0.027
 10     10  0.0  91525.516 -353419.88  91525.510 -353418.95  0.071 -0.928
 12     12  0.0  91519.617 -3530 8.93  91519.610 -3530 8.57  0.082 -0.358
 13     13  0.0  91514.504 -353236.57  91514.520 -353237.03 -0.197  0.465
 14     14  0.0  91511.748 -353319.47  91511.760 -353319.87 -0.142  0.399
 16     16  0.0  915 8.275 -353421.52  915 8.250 -353421.76  0.311  0.240
  RMS in X-direction (arcsec):  0.159
  RMS in Y-direction (arcsec):  0.435
 

The transformation parameters are listed in 0.001 deg/encoder unit.

 


---

 


--oOo--