From Mustafa's Comparison of TPC super-sectors alignments, I used the parameters found here:

Yuri old: http://www.usatlas.bnl.gov/~fisyak/star/Tpc/Alignment/Global/TpcSuperSectorPositionB.20140101.001112.png
Yuri new: http://www.usatlas.bnl.gov/~fisyak/star/Tpc/Alignment/Global/TpcSuperSectorPositionB.20140101.001454.C
Alex: http://www.star.bnl.gov/protected/heavy/mstftsm/tpc/alignment-using-hft/comparison-of-different-alignments/TpcSuperSectorPositionB.20140103.000002.C

...and compared them to each other graphically. Here are the 6 parameters directly compared (Alex's parameters are on the vertical axis and begin with "a", while Yuri's are on the horizontal and begin with "y" and are blue for their old values, and red for their new values), all units [cm] and [rad]:



Alex constrained alpha & beta to be the same as Yuri's old alpha & beta.

Yuri has noted that (as has historically been true using the TPC only), there is no sensitivity in the TPC-based calibration to the difference between y0 and gamma, so the choice has been made here to use y0 solely and set gamma=0.

For Alex, using HFT tracklets, there is sensitivity to both of these, so they have been calibrated separately. It is worth comparing the two methods by estimating the impact of gamma on y0, which I tried to do here (assuming 123 cm projection to the vertex for the angle gamma):

(not sure I did this comparions properly....stricken for now)...
If anything, it appears these are anti-correlated (was the wrong sign chosen by someone?).

Lastly, here are the parameters vs. sector (green is Alex's parameters, blue is Yuri's old, and red is Yuri's new):


-Gene