B^- to D⁰ (K pi) K*^-

Current status

ntuple

ntuple is stored at /opt/ppd/lhcb/tbird/ntuples/B2DKstar/data/B2DKstar_str09.root

cuts

Using Almost exactly same cuts as B2Dpi, except cuts applied to daughters of the D were also applied to the daughters of the K* and a mess cut was applied to the K* too, with a window of 150 MeV.

The names were defined for the B2Dpi decay so are not as useful as they are for that decay

#define Name_Of_Cuts  "thomas mod - low mv and dipchi2"

#define Negative_D_Daughter_PT_Cut               300
#define Positive_D_Daughter_PT_Cut               300
#define Negative_D_Daughter_MINIPCHI2_Cut        9
#define Positive_D_Daughter_MINIPCHI2_Cut        9
#define Negative_D_Daughter_P_Cut                2000
#define Positive_D_Daughter_P_Cut                2000
#define Negative_D_Daughter_TRACK_CHI2NDOF_Cut   8
#define Positive_D_Daughter_TRACK_CHI2NDOF_Cut   8

#define Bachelor_PT_Cut                          300
#define Bachelor_MINIPCHI2_Cut                   9
#define Bachelor_P_Cut                           2000
#define Bachelor_TRACK_CHI2NDOF_Cut              8
#define Bachelor_PIDK_Cut                        100000

#define D_FDCHI2_OWNPV_Cut                       100
#define Z_Dist_Cut                               -1
#define D_ENDVERTEX_CHI2_D_ENDVERTEX_NDOF_Cut    15
#define D_IPCHI2_OWNPV_Cut                       9
#define D_PT_Cut                                 2000

#define B_FDCHI2_OWNPV_Cut                       64
#define B_ENDVERTEX_CHI2_B_ENDVERTEX_NDOF_Cut    10
#define B_IPCHI2_OWNPV_Cut                       16
#define B_DIRA_OWNPV_Cut                         0.9999

#define Negative_D_Daughter_PIDK_211_Cut         10
#define Positive_D_Daughter_PIDK_211_Cut         10
#define Positive_D_Daughter_PIDK_321_Cut         10
#define Negative_D_Daughter_PIDK_321_Cut         10

#define D_M_Window_Cut                           21

#define B_M_Window_Cut                           50

these are saved in /home/hep/uoh35620/stuff/analyse-n-tuple/cuts/thomas.low.dip.cuts.h

this is a version of /home/hep/uoh35620/stuff/analyse-n-tuple/cuts/thomas.low.mv.cuts.h where the D IP Chi^2 has been loosened, when it was a bit tighter the monte carlo efficiency was as follows

Cut info:
0    tot lumi   : -5.00e+12 nb-1 +/- 5.00e+12 nb-1
0    tot cands  :   153263
1    evt bfr cut:    16662
2    D daughter :    13075  78.47% +/-   0.32%
3    bachelor   :     9759  74.64% +/-   0.38%
4    after D cut:     6700  68.65% +/-   0.47%
5    after B cut:     6134  91.55% +/-   0.34%
6    after PID  :     4300  70.10% +/-   0.58%
7    nPV        :     4300 100.00% +/-   0.00%
8    event num  :     4300 100.00% +/-   0.00%
9    D mass     :     4024  93.58% +/-   0.37%
9    B mass     :     3868  96.12% +/-   0.30%
     Overall Eff:           23.21% +/-   0.33%

analysis script

• KstarAnalysis.C: The Kstar analysis script

Run it with the g++root command defined HowToCompileRootMacros it took ~15 hours to run with 577/nb of data, so run it on heplnx112 not 108 as 108 is slow.

plots

raw plots can be found in /opt/ppd/lhcb/tbird/analysis/b2dkstar/* for mc and data. the name of the cuts used is specified in the KstarAnalysis file and the output file, both near the top.

• B2DKstar D mass plot with 577/nb:
  

• B2DKstar B mass plot with 577/nb:
  

-- ThomasBird - 2010-09-07