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Tests using Monte Carlo
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1. Comparison between updated Monte Carlo and Honguo's original version ( called mcnodbgsrc) with the updated MC still using the old iterative approach to correcting the target quantities for the vertical beam position. A plot of the difference between the initial delta, xptar ( vertical angle), yptar (horizontal angle) and ytar and the reconstructed quantitites for carbon target ( cnohe.tgt) and HMS central momentum setting of 3590 ( rssvlonob.inp) with radiative and multiple scattering turned on. The updated MC ( called old_pol_hms_single in plot) and the original version agree.

2.  Comparison between updated Monte Carlo and Honguo's original version ( called mcnodbgsrc) with the updated MC using the new approach to correcting the target quantities for the vertical beam position . A plot of the difference between the initial delta, xptar ( vertical angle), yptar (horizontal angle) and ytar and the reconstructed quantitites for carbon target ( cnohe.tgt) and HMS central momentum setting of 3590 ( rssvlonob.inp) with no radiative effects and no multiple scattering. The updated MC ( called pol_hms_single in plot) has much better resolution resolution in all target quantities. Plots of difference between initial and reconstructed xptar , delta, yptar and ytar versus the focal plane x,xp,y and yp for the updated Monte Carlo. Plots of difference between initial and reconstructed xptar , delta, yptar and ytar versus the focal plane x,xp,y and yp for the original version.

3.  Comparions between new and original Monte Carlo for carbon with high and low HMS setting and different target field directions. Radiative and multiple scattering were turned on. The plots ( Diff in the table ) of the difference between the initial delta, xptar ( vertical angle), yptar (horizontal angle) and ytar and the reconstructed quantitites are similar for the updated version for both momentum settings for a given target field setting. The updated version is an improvement over the original except for yptar which is similar for both versions. Looking into details of the updated MC, the perp target field has a worse resolution in the xptar difference when compared to the para target field. The differences for the other target settings are similar between the different target field settings. The plots of xptar, yptar, delta and ytar are shown in the link Target in the table. The yptar and delta are similar between the original and updated Monte Carlo. In all types of runs the ytar is improved. The xptar is similar between the original and updated versions for the parallel setting, though it is slightly wider in the updated version. For the perp setting, the xptar is a little different. For the updated version the xptar is slight wider and the distribution of events is different. Both the high and low HMS setting with perp target field are similar. Even with all of this, the plots ( W in the table) of the W distribution are similar between the original and updated version.

4. Comparison between updated MC and data for Run 43204. All plots have cut of abs(delta) .lt. 8 with hsp .gt. 0.and.0.8 .gt. hsshtrk/hsp .lt. 1.4 in addition for data. The y-axis in the plots ( with one noted exception) is the rate scaled to 100nA. Looking at the "Beam" plots one can see that the Monte Carlo needs to be shifted in xbeam ( +x is beam right), ybeam (+y is up), and zbeam (+z is downstream). With these shifts one can see a definite improvement in yptar ( see "Target" plots). The ytar is improved with the shift but the MC is narrower than the data while the xptar,yptar and delta agree nicely. The "W" plot compares the data to the MC with the MC scale by the factor given in the top plot ( same scale factor used in all plots). The bottom plot in the "W" plots is the ratio of data/MC with the MC scaled by the factor. With the shifts in beam and target position the MC better agreement with the data below 1.8 and above 2.1 . The error bars in the ratio are from the MC and data( there are typically about 300K successful events in the MC). ( Updated Feb 29th, 2004) The charge, time, deadtimes etc are listed in run list.

5. Comparison between updated MC and data for Carbon parallel target field. All plots have cut of abs(delta) .lt. 8 with hsp .gt. 0.and.0.8 .gt. hsshtrk/hsp .lt. 1.4 in addition for data. The y-axis in the plots ( with one noted exception) is the rate scaled to 100nA. ( Updated Feb 29th ,2004)

6. Comparison between updated MC and data for Carbon perpendicular target field. All plots have cut of abs(delta) .lt. 8 with hsp .gt. 0.and.0.8 .gt. hsshtrk/hsp .lt. 1.4 in addition for data. The y-axis in the plots ( with one noted exception) is the rate scaled to 100nA. ( Updated August 12th, 2004)

6. Comparison between updated MC and data for Carbon parallel target field for one high momentum setting of HMS at 4948 GeV/c. All plots have cut of abs(delta) .lt. 8 with hsp .gt. 0.and.0.8 .gt. hsshtrk/hsp .lt. 1.4 in addition for data. The y-axis in the plots ( with one noted exception) is the rate scaled to 100nA. ( Updated August 12th, 2004)

7. Look at NH3 perpendiclar runs 43261 and 43383 at HMS central momentum of 4.703 and 4.961 GeV/c. Plots of the peak position of W for runs 43261 and ( Updated Mar 6th, 2004)