Changes between Initial Version and Version 1 of PS1_GPC1_Rotator_20080915

Timestamp:

Mar 2, 2009, 9:04:59 AM (17 years ago)

Author:

eugene

Comment:

--

PS1_GPC1_Rotator_20080915

@@ +1 @@
+up to [wiki:PS1_GPC1_Rotator_Measurements]
+
+2008.09.15
+
+i've been trying to understand the effects I am seeing in the rotator
+sequences from 2008.08.27 which I wrote about on friday.
+
+I was not happy with the fits I had to the sequences.  I found a minor
+bug and that improved things a bit, but there were still significant
+residuals.  I decided to plot the residuals.  Attached are pairs of
+plots for each altitude set (30,50,70).  Notice the clear 2*POSANGLE
+term in the residual, which scales with the zenith distance.  I'm not
+fitting for a 2*POSANGLE term, and I'm not sure I see what that
+corresponds to.  any ideas?
+
+fyi, i've also attached the data files with the measured boresite
+offset and the POSANGLE values for each sequences.  Below are my fits:
+
+Xo,Yo : center of the ellipse
+RX, RY : major and minor axes of the ellipse
+P0 : position angle of the ellipse in radians
+T0 : phase lag between POSANGLE and the major axis.
+
+the fitted ellipse has the form:
+
+X = Xo + RX*cos(PA-T0)*cos(P0) + RY*sin(PA-T0)*sin(P0)
+Y = Yo + RY*sin(PA-T0)*cos(P0) - RX*cos(PA-T0)*sin(P0)
+
+==> rotseq.30.pars <==
+# fitted values:
+Xo:  45.276222
+Yo:  -9.302365
+RX:  145.009399
+RY:  67.481323
+P0:  0.646367
+T0:  0.357436
+
+==> rotseq.50.pars <==
+# fitted values:
+Xo:  21.140253
+Yo:  -14.027387
+RX:  108.704620
+RY:  59.530045
+P0:  0.587284
+T0:  0.475980
+
+==> rotseq.70.pars <==
+# fitted values:
+Xo:  10.799451
+Yo:  -14.946221
+RX:  75.923729
+RY:  53.394173
+P0:  1.152103
+T0:  0.182733
+
+aloha
+gene