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Further adjustments to zero-points of SMU tables & Telescope pointing
Most recent changes to SMU parameters X_ZERO Y_ZERO were made on 20071214. Last night (UT20071220) was the first time since then that RxA data had been acquired. Logged data were as follows:
HST AZ EL X Y Z T_legs (degC)
18:25 303 48 -0.12 -0.36 0.09 4.2
21:10 412 59 -0.01 3.6
23:25 350 73 -0.17 0.04 0.21 2.6
01:25 306 56 -0.28 0.02 -0.13 1.8
04:40 220 81 -0.03 0.03 0.18 0.9
Means -0.15 -0.07 0.07
s.d. 0.10 0.20 0.14
There is justification, perhaps, in adjusting X_ZERO by a further -0.15mm.
This would precipitate a change to the elevation pointing of
of -0.15 * -30.25 = +4.5", requiring a compensatory adjustment to IE of
+4.5" (see the sign convention).
X_ZERO was adjusted from -25.10mm to -25.25mm, and IE from -48.79 to -44.29 at 12:40 HST 20 Dec 2007. HARP focus data from 15-19 Dec are shown below:
UT date HST AZ EL X Y Z T_legs (degC)
15 19:20 301 41 -0.27 0.11 0.40 1.4
15 22:48 99 47 - - 0.30 0.3
15 01:10 262 53 -0.39 -0.05 - -0.8
16 18:40 303 48 -0.28 -0.42 0.46 0.2
17 19:20 302 40 -0.38 -0.09 0.55 0.4
17 21:55 405 65 - - 0.39 -1.0
17 23:05 370 73 -0.24 0.01 - -1.3
18 18:35 208 60 -0.26 0.01 0.47 2.5
18 23:00 370 73 -0.10 0.07 0.34 -0.7
18 04:25 265 34 - - 0.25 -0.9
19 18:25 206 61 -0.27 0.04 0.37 4.4
19 21:50 404 65 - - 0.31 3.1
19 03:28 301 33 - - 0.18 1.9
19 04:00 288 45 -0.32 0.20 0.16 1.4
Mean -0.28 -0.01 0.35
s.d. 0.09 0.17 0.12
Mean HARP - RxA -0.13 0.06 0.28
These latter (difference) values should find their home in
/jac_sw/itsroot/src/harpb/XML/instrument_harpb.ent
and are put there at 12:10 HST on 21 Dec 2007.
They will introduce (see sign conventions)
telescope offsets of -0.13 * -30.25 = +3.9" in elevation
and +0.06 * -28 = -1.7" in azimuth, requiring corrective collimations
for HARP (w.r.t. the RxA pointing model) of (-1.7",-3.9") in (CA,IE).
These are currently set at (+18.0",+28.0") although
recent data
are best fit by (+14.4",+34.7").
Together these suggest that new values of (CA,IE) in the above .ent
file should be (+12.7",+30.8"). Rounded values of (+13,+31) were installed
at 13:15 on 21 Dec 2007.
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