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seconditr

Heep results after iteration 02/22/06 (rev. 02/23/06)

After inserting the offsets from 02/16/05 into replay, the peaks were shifted from zero by up to 7 MeV (link).  This was found to be due to using approximate offsets for dth_ss, dth_hs, dp_ss and dp_hs.

Therefore, the approximate offsets were used for these quantites and dE and dp_ss were optimized again to center the peaks near zero.  Here are the new offsets.
Ebeam(GeV)
 P hms(GeV)
 TH hms(deg)
 P sos(GeV)
 TH sos(deg)
 dE
 dth_ss
 dp_ss
 dth_hs
 dp_hs
 dssxptar
2.038
 -1.692
 25.005
 0.874
 54.90
 0.0
 0.0
 0.42
 0.3
 1.5
 0.00368
5.012
 4.116
 18.70
 -1.7227
 50.00
 0.0+0.8
 0.0
 10.51-0.8
 0.3
 1.5
 0.00753
5.766
 4.867
 16.19
 -1.6868
 51.61
 0.0-0.8
 0.0
 6.92+0.8
 0.3
 1.5
 0.00674
4.021
 3.232
 22.15
 -1.588
 50.00
 0.0+0.5
 0.0
 2.57-0.4
 0.3
 1.5
 0.00533


For reference, here are the results from before the iteration
Ebeam(GeV)
 P hms(GeV)
 TH hms(deg)
 P sos(GeV)
 TH sos(deg)
 dE
 dth_ss
 dp_ss
 dth_hs
 dp_hs
 dssxptar
2.038
 -1.692
 25.005
 0.874
 54.90
 0.0
 0.8
 0.5
 1.0
 1.5
 0.0036
5.012
 4.116
 18.70
 -1.7227
 50.00
 0.0
 -0.3
 10.2
 0.2
 2.4
 0.008
5.766
 4.867
 16.19
 -1.6868
 51.61
 0.0
 0.05
 7.65
 -0.05
 0.8
 0.0062
4.021
 3.232
 22.15
 -1.588
 50.00
 0.0
 0.0
 1.9
 0.3
 2.15
 0.0052

The iteration shows that that fit for dp_ss needs to be closer to the heep determined offsets in the second table (the shift in dp_ss from the iteration is in the direction to correct the fit).

The plots showing the positions of the peaks are here.
They should be compared to the plots here.

The peaks are now centered within about 2.5 MeV of zero, compared to 5 MeV before the iteration.

The new parameterization of dp_ss is shown below

The solid line is the parameterization
-0.4792+0.0000026*exp(x**5)-0.0028897*exp(x**4)
Note that the parameterization should not be used above 1.7227 GeV. 
For P_sos>1.7227 GeV, use Tanja's parameterization (dashed line)
-0.36-0.0632*exp(x**3.004)

Here is the table of differences
P sos(GeV)
 dp_ss (heep)
 dp_ss (fit)
0.874
 0.42
 0.48
-1.7227
 9.71
 9.69
-1.6868
 7.72
 7.74
-1.588
 2.17
 2.09