The last report was on 20081203. This report is an analysis of data from December.

Without any adjustment for nightly collimation differences, they behave as follows:

   Dataset   FE     No.    CA  +- dS      IE  +-  dZ
                             (daz)          (del)
   200812    A     220   -1.06 +-  2.1   -1.23 +- 3.2 

   200812    H      63   +16.3 +-  4.2   +32.5 +- 2.6
 

These are displayed below; RxA on the left and HARP on the right:

As before there are no strong trends in the RxA data, and while there remains a strong trend of dS-vs-Z in the HARP datasets (centre-left frame in right-hand plot), now visible in both dS and dZ. The likely cause of this are terms, as yet unaccounted for, in the K-mirror model.

The combined HARP performance statistics undoubtedly also include contributions due to the absence of a K-mirror model.

Focus

 Month  FE    Axis   N    mean     +-            Notes
 -----  ----  ----  ---  ------- ------  ---------------------------
  Dec   RxA     Z    87   0.18    0.15       1 < Tmean < 11
                X    22   0.07    0.13
                Y    22   0.12    0.02              

  Dec   HARP    Z    22   0.19    0.11       3 < Tmean < 12
                X     7  -0.07    0.09     
                Y     8  -0.04    0.18 

 Dec:  HARP_Z  = (+0.12 +- 0.15)*sin(el) s.d. 0.10
 Dec:  RXA_Z   = (+0.09 +- 0.12)*sin(el) s.d. 0.15

Click below for plots of

• 2008 Dec RxA Tmean-vs-Z
• 2008 Dec HARP Tmean-vs-Z

• The trends mentioned in the previous report are less apparent in this months data.
• It appears the trends seen in HARP may be associated with a RxA trend after all. Hopefully this removes a focal station effect as a possible cause - phew!

Previously a downward trend has been identified during the first half of the night in the Z-vs-UT plot. This remains apparent in the December data.

• 2008 Dec RxA UT-vs-Z
• 2008 Dec HARP UT-vs-Z