Pointing with RxA in spectral line mode recorded 38 data, which are shown below on the basis of yesterday's pointing model:

RMs residuals in (dS,dZ) or (daz,del) are (8.8",4.4") ! Optimizing all 7 parameters of the TPOINT model led to this distribution:

with performance on the sky of (dS,dZ) = (daz,del) of (7.8", 3.1"). 11 logged data were probably preliminary results, followed by repeated measures, so these were eliminated and the data re-reduced:

Performance on the sky is now (dS,dZ) = (5.3", 3.2"); which is rather poor, but with no obvious systematic trends unaccounted for. In mitigation: the conditions were rather poor (some thick-ish cirrus around, and tau~0.18) and the chop frequency of 1.4836795 Hz is rather slow for continuum work and perhaps, we may find, for spectral line pointing also.

The residuals are shown in the table below:

          *HA           *Dec      *Az   *ZD     dX     dD     dS     dZ     dR

   1  +00 48 12.53  -14 38 43.9  199.9  36.5
   2  +00 52 31.29  -14 38 44.3  201.5  36.8
   3  +01 10 29.93  -14 38 45.9  208.0  38.6   -5.0   -2.3    5.5   -0.2    5.5
   4  +04 33 01.25  +04 37 26.2  266.9  68.0
   5  +04 36 40.90  +04 37 25.1  267.3  68.9    0.1   -5.3    5.0    1.9    5.3
   6  +03 38 42.52  +02 01 22.6  258.7  56.3    4.4    6.8   -7.9    1.4    8.1
   7  -04 14 03.95  +36 43 16.5   58.4  57.4
   8  -04 07 26.24  +36 43 15.5   58.4  56.1   -1.1    1.1    1.1    1.1    1.5
   9  +00 08 13.18  -42 51 49.4  181.7  62.7   -8.3    4.3    8.2   -4.6    9.4
  10  +00 39 54.62  -24 29 00.3  192.8  45.4
  11  +00 46 23.18  -24 29 00.2  194.8  45.7    1.7   -3.0   -0.8    3.4    3.4
  12  -01 29 49.03  +01 15 40.5  127.5  28.8   -5.1   -0.4    3.0    4.1    5.1
  13  +02 50 34.34  -14 38 51.1  233.8  54.3    3.8    0.3   -2.6    2.8    3.8
  14  +03 25 07.44  +25 40 37.0  287.1  47.4    1.4    0.5   -0.6    1.3    1.4
  15  -02 40 08.40  +36 43 07.9   55.5  38.7   -2.5    7.1    6.2    4.2    7.5
  16  -02 49 49.17  -15 36 36.1  127.2  54.7
  17  -02 41 25.87  -15 36 37.1  128.8  53.2    2.2    1.8   -0.0   -2.9    2.9
  18  +00 01 14.55  +01 15 39.5  181.0  18.6
  19  +00 05 39.68  +01 15 39.5  184.4  18.6    5.4    3.0   -5.6   -2.6    6.2
  20  +01 52 39.66  -35 46 41.2  205.8  61.7    9.7    6.6  -11.7   -0.8   11.7
  21  +00 07 23.11  +10 51 41.7  191.5   9.1
  22  +00 11 23.52  +10 51 41.7  197.4   9.4    3.9   -1.8   -3.2    2.8    4.3
  23  -03 18 37.64  -07 20 03.5  114.1  55.9
  24  -03 10 22.71  -07 20 04.8  115.3  54.1    0.7  -11.1   -9.9    5.1   11.1
  25  -02 55 25.02  +16 11 11.5   87.6  41.8
  26  -02 40 46.72  +16 11 10.6   88.8  38.3   -7.8   -4.7   -3.1    8.6    9.1
  27  -00 41 59.96  +36 43 04.6   26.3  19.2    3.3    5.4    5.7    2.9    6.4
  28  -02 22 33.15  -07 20 10.3  124.3  44.4    4.7   -3.0   -5.2   -1.8    5.5
  29  -00 41 07.38  -15 36 44.9  163.3  36.9   -4.0    0.4    3.9    0.7    4.0
  30  +01 32 42.03  +10 51 42.7  251.6  24.0   -3.2   -4.2    5.2   -1.1    5.3
  31  -00 07 34.52  +36 43 04.4    5.2  17.0    3.8    1.2    3.9    0.8    4.0
  32  +00 59 18.57  +33 33 46.1  319.2  19.0   -7.1    2.8   -6.8   -3.4    7.6
  33  +03 21 39.52  +58 12 53.1  329.4  52.8
  34  +03 51 32.72  +58 12 56.7  327.7  56.5   -4.8   -6.4    4.7   -6.5    8.0
  35  -02 28 17.01  +69 40 21.2   14.9  54.6    2.7    1.4    2.9   -0.9    3.1
  36  -04 22 25.20  +61 53 49.1   29.3  61.2    0.8    5.4    5.5    0.3    5.5
  37  -00 59 28.33  +61 28 56.2   10.4  42.9   -1.6   -3.6   -2.7   -2.8    3.9
  38  -01 13 32.81  +43 34 59.3   28.8  28.3    0.0    0.4    0.2    0.3    0.4
                                                dX     dD     dS     dZ     dR
                                        RMS     4.41   4.37   5.30   3.23   6.21

There is no obvious thermal effect - i.e. no trend of elevation residuals, dZ, with time or sequence-number. (A way to display this is currently not available). The model generated is

JCMT Pointing Test - 2006/08/23
T   27   6.2102   38.999  -0.0412
  IA       -117.4368    21.19496
  IE        -17.1666     3.74933
  NPAE     +155.5644    25.78972
  CA       -324.1160    31.75562
  AN         +5.6741     1.37616
  AW        -16.4823     1.36845
  TF         -8.6924     5.51516

CCW Inclinometry followed:

    Datasets  El Dirn     HST     mean leg temperatures   Humidity
                          start     start   middle   end       %
  ( 20060821  89  cw      00:29      8.0      7.4    7.0      -- 
    20060822  89  cw      18:00       -        -      -       -- )
    20060824  89 ccw      04:00      8.1      7.5    7.1      --

The datafile was given a UT-related name. Data is recorded from the 3 active inclinometers only: there is no strain gauge data, for instance.

The raw data from channels 2,5,8 (Y-axes) are shown below:

The TY data are of the 'low-amplitude' variety seen in the CW run of 20060820 rather than the normal variety seen in the CW run yesterday and previously - i.e. in and before January 2006. This feels both spurious and worrisome. Yesterday's run was preceded by the resetting of the 'Filter' switch in the cabin, so it's possible that this switch has been mis-set again. Otherwise, if the physical state of the inclinometer has remained unchanged in the last 36 hours then a CW & CCW pair may be needed to reveal what determines the TY amplitude.