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Hi all, here are the results from the tests concerning the differences in the D** modeling we talked about this morning. This is done with Concezio's recent VVF tag and the correction factors are picked up from corrratiosigpeakmx_newdatadepl.txt. The D** are moved into the "other" component (-fitdss 1). Please find the plots here: http://costard.lbl.gov/~kerstin/vubunf/testdss_Run12fitresults.eps http://costard.lbl.gov/~kerstin/vubunf/testdss_Run4fitresults.eps By eye, the fits do look different and here are some numbers: **Fit on Run 1+2, SP5: chi2/ndof = 1.64116 (for 7 dof) ratio other/vcb = 0.296045 / 0.287339 = 1.03 +- 0.17 (with errors: Vcb comp = 0.287339 +- 0.0183957 Oth comp = 0.296045 +- 0.0442523) **Fit on Run 4, SP6: chi2/ndof = 1.90748 (for 7 dof) ratio other/vcb = 0.117799 / 0.141224 = 0.83 +- 0.13 (with errors: Vcb comp = 0.141224 +- 0.00785652 Oth comp = 0.117799 +- 0.0174853) where vcb is D and D*, other is D** and the non-sl bkgd. The differences might or might not be from the D** - roughly, in SP6 we would think that the D** should smear down to smaller masses (since some widths are larger and the minimum masses, with which D** can be produced can be lower). We subtract less "other" and still the data spectrum has fewer entries in the bins around 2GeV (and the D** do smear this far down). Here is another observation from these fits: Run 1+2, SP5, numbers of events in the first mX bin: Data 1' bin = 393.016 +- 26.1089 Vub 1' bin = 1809.31 +- 45.3825 Vcb 1' bin = 482.67 +- 22.7482 Oth 1' bin = 73.6857 +- 9.62637 Run 4, SP6, numbers of events in the first mX bin: Data 1' bin = 436.967 +- 27.2767 Vub 1' bin = 1528.4 +- 41.7351 Vcb 1' bin = 1327.69 +- 37.7632 Oth 1' bin = 186.534 +- 14.9827 after the mES fit... compare the number of data events (quite similar) and the number of Vcb events (quite different). As far as I know there is no SP5/SP6 weight on the generic MC. In the case that we think efficiencies might be sensitive to the run period, this looks like a potential problem, doesn't it? And taking Run 3 into account, this looks even worse. I am confused - I thought we were supposed to have SP5 and SP6 roughly in the ratio of Run1-3 to Run4. And if this is true before any cuts and bkgd subtraction, it probably should not be vastly different afterwards. Cheers, Kerstin