UT20080113: New HARP arc data - sequences of H10-centred FIVEPOINTs - were obtained at CO:3-2 (345GHz) on CRL618 and irc+10216, with the K-mirror parameters all set to zero:

1. EL=28 : with 31 > Elevation > 25 (CRL 618)
2. EL=80 : with 78 < Elevation < 83

The results of the centroid fitting are as follows:

   #      AZ       EL     X(daz) Y(del)  IMG_ROT=2K 
  50   301.4741  25.0316  -4.42   1.31   -104.85
  51   301.6038  24.1639  -4.47  -0.04    -65.78
  45   300.9886  29.5142  -3.57  -0.38    -60.37
  49   301.3763  25.7903  -4.00  -0.59    -54.10
  48   301.2889  26.5470  -1.24  -1.61     -3.39
  43   300.8780  31.1879   0.77  -0.15     31.28
  44   300.9338  30.3817  -0.00  -0.42     30.48
  47   301.2073  27.3093   0.52   0.65     47.30
  46   301.1280  28.0813   1.19   2.18     98.07

  61   235.4296  78.7309  -2.65  -0.18   -104.09
  60   232.1333  79.4982  -0.75  -1.08    -53.30
  55   198.1578  83.0284   1.05  -0.17     -6.92
  53   182.1966  83.3654  -0.32  -0.12     -6.66
  52   173.3118  83.3294   3.18   0.68     -6.62
  59   228.5131  80.2052   1.57  -0.37     -2.70
  57   216.1307  81.8614   2.26   1.77     48.95
  54   190.4486  83.2576   1.05   2.27     83.20
  56   209.8922  82.3959   0.73   3.81     99.43

The data are shown below, with the red circles being the best fits based on the 6-coefficient solution from these (18) data alone. These are the second arc data since the mirror adjustment of 20070920, after those on 20071005.

The raw data have rms errors in (daz,del) of (1.8",1.7") and (2.8",1.1") respectively, while the fitted data have rms's of (1.0",0.5") and (0.6",0.4"). The fit is the parameter set (x0, y0, x1, y1, x2, y2) = (-1.1, 1.4, -3.9, -2.5, -2.5, 0.0) - which may be compared, for instance, with ( 1.1, 1.1, 4.4, -0.5, 0.0, 0.0) as determined on 20071005. The solution derived from the combined 20071005 and 20080113 data (all the post-mirror-adjustment data) is (-1.1, 1.2, -4.2, -2.6, -2.7, 0.5), which seems dominated by these most recent data.

As before, however, the (49?) allsky HARP pointing data reported recently are not coherently improved by subtraction of these kmirror corrections.