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CLEO-c D + s         e   e  

Prof. Sheldon Stone, Dr. Liming Zhang Speaker : Chun-Min (Mindy) Jen Syracuse University on behalf of CLEO collaboration. CLEO-c D + s         e   e  . Basic Technique for D + s         e   e   (review). Fully reconstruct D - S single-tags.

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CLEO-c D + s         e   e  

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  1. Prof. Sheldon Stone, Dr. Liming Zhang Speaker : Chun-Min (Mindy) Jen Syracuse University on behalf of CLEO collaboration CLEO-cD+s ee Group Meeting Chun-Min Jen

  2. Group Meeting Chun-Min Jen Basic Technique for D+s ee (review) • Fully reconstruct D-S single-tags. • Search for events with one additional signal identified as an e+ in addition to the D-s single-tags. • The extra energy (Eextra) in the events is the energy found in the event minus that of the tag plus the e+ . (Eextra includes the g or p0 from Ds* decay.)

  3. Group Meeting Chun-Min Jen Reconstruction of Tag events & Signal-e+ selection criteria (review) g • 9 Single-Tag sides (full reconstruction): • D-s  K+ K- p- • D-s  KS K- • D-s  h p- • D-s  h’ p- • D-s  K+ K- p- p0 • D-s  p+ p- p0 • D-s  K*0 K*- • D-s  h r- • D-s  h’ (r g) p- • EID cut > 0.8 • Electron's momentum > 0.2 GeV • |COS θe| < 0.8 for signal e+ • w/o split-off cut (split-off approved) & |COS θ| < 0.9 for showers p0 g Eextra‏ counting from neutral showers with photon energy > 30 MeV D+S D*±S g D±S D-S e+ e- ne Ec.o.m.= 4170 MeV NDT≡ Ne+ + NST D-/+S D-S e+ t+ D+S K+/p+ from the wrong- side of D-S may fake into e+ nt n

  4. Group Meeting Chun-Min Jen News (after June 26th CLEO-meeting)‏ • Cross-Check: • Comparison of the input generic MC B.R. with what we measured, based on generic MC, for D+s  ee • Issues: • Determination ofsignal e+ efficiency in data and MC, respectively --- Dr. Zhang will work on it! • Measurement for inclusive B (Xe+ne) and relevant studies of backgrounds derived from D+S X e+ne

  5. Group Meeting Chun-Min Jen • A Couple of News : • re-generate 100K signal MC samples w/ new library and new decay tables for Exp.41 and Exp.48, respectively • re-generate generic MC (18.9x data) w/ NEW library • obtain the number of K±/p± fake to e+ in data and generic MC, respectively • compare the input generic MC branching fraction in the decay table with what we measured based on all data-set generic MC samples • Background studies for inclusive Xe+ne (not yet finish)

  6. Group Meeting Chun-Min Jen I : Determine e+ efficiency : Both of NDT and NST are from tag in signal MC……

  7. # of Tags (New Signal MC_100K for Exp.48)‏ NSTsig.MC = 30034±173 ; NDTsig.MC = 19524±140 Real-Red: 1) Double-Gaussian 2) One-sigma Gaussian Dotted-Blue: 1st-order Polynomial Dash-Blue: Ds signal mass Group Meeting Chun-Min Jen

  8. # of Tags (New Signal MC_100K for Exp.41)‏ NSTsig.MC = 29905±184 ; NDTsig.MC = 19355±139 Real-Red: 1) Double-Gaussian 2) One-sigma Gaussian Dotted-Blue: 1st-order Polynomial Dash-Blue: Ds signal mass Group Meeting Chun-Min Jen

  9. Tag Modes Invariant Mass Signal Invariant Mass Signal – eid-cut; Pe+>0.2 GeV ; abs (cosΘe) < 0.8; Eextra<0.4 GeV # of Single-Tag # of Double-Tag  10711±104 6779±82 S 2531±50 1745±42  1511±39 1061±33 ’ 950±31 668±26  4162±65 2349±49  3005±55 2105±46  1811±43 1099±33  3436±59 2400±49 ’ 1917±44 1318±36 SUM 30034±173 19524±140 Table I. # of Tags (New Signal MC_100K for Exp.48)‏

  10. Tag Modes Invariant Mass Signal Invariant Mass Signal – eid-cut; Pe+>0.2 GeV ; abs (cosΘe) < 0.8; Eextra<0.4 GeV # of Single-Tag # of Double-Tag  10660±101 6727±82 S 2632±50 1799±42  1452±48 1025±32 ’ 969±31 638±25  4210±79 2408±49  2966±55 2031±45  1758±42 1073±33  3346±68 2355±49 ’ 1913±45 1299±36 SUM 29905±184 19355±139 Table II. # of Tags (New Signal MC_100K for Exp.41)‏

  11. Group Meeting Chun-Min Jen Signal MC PDFsNew Signal MC_200K for Exp.41 + Exp.48

  12. Group Meeting Chun-Min Jen II : Eextra from Semi-leptonic decays • Since we use Eextra to discriminate between Be+ and B (D+s X e+), we need to know the distribution from the semi- leptonic decays. • What do we know about semi-leptonic decays? B(D+St+; t+ e+nent)‏ B ( D+Se+ e )‏ D+S’e+ e D+S K*0 e+e D+S e+e D+S f0 e+e B( D+SL e+e )‏ g not detected Cabibbo-Suppressed inclusive D+S X e+e # of events / Bin/ 100 MeV S  non-peaking background  Peaking background Eextra (GeV)‏ 0.9 – 1.0 0.4

  13. # of Tags (New Generic MC_18.9x data)‏ NSTgen.MC=1256946±2762 Real-Red: 1) Double-Gaussian 2) One-sigma Gaussian Dotted-Blue: 1st-order Polynomial Dash-Blue: Ds signal mass Dash-Green: Ds sideband Group Meeting Chun-Min Jen

  14. Tag Modes Invariant Mass Signal # of Single-Tag  459378±305 S 109167±149  59216±110 ’ 40180±90  172426±186  134232±164  76772±125  130093±162 ’ 75482±124 SUM 1256946±2762 Table III. # of Tags (New Generic MC_18.9x data)‏

  15. Group Meeting Chun-Min Jen Generic MC studies (New 18.9x data)Generator_Level Background Sources

  16. Group Meeting Chun-Min Jen Methodology of constraints on pure BG shapes in One-Dim. Fit for Eextra distribution • P1 = D+s ee (signal yields =NDTData)‏ • P2 = D+s  KLe( peaking background ; fixed)‏ • P3 = D+s e ( the dominant source of the pure, i.e. non-peaking, background )‏ • P4 = D+s ’enon-peaking background )‏ • P5 = D+s e…… • P6 = D+s e…… • P7 = D+s  f e…… • Constraint on BG shapes ( one float variable + weight=SC_rel.i ): • Norm (Pi) = Br.i * SCi ( ≡ NSTData / NSTsig.MC) = P3 (Br.(e+* SCi) * SCrel.i • SCrel.i ≡ Br.Xe+e ( NSTData / NSTsig.MC )Xe+e / Br.e+e( NSTData / NSTsig.MC )e+e float constraint by P3 float variable

  17. Group Meeting Chun-Min Jen Generic MC (New 18.9x data)–B.R.measurement • Єsig.MC (New) = 0.648±0.006 (100K for Exp.48) ; Єsig.MC (New) = 0.645±0.006 (100K for Exp.41) • NSTgen.MC=1256946±2762 ; NDTgen.MC= 29857±177 ; NDTgen.MC (inside Eextra < 0.4 GeV) =10760±104 • Tag-Bias = 1.022±0.003 ; B (D+SK0S e+ne) = 0.343 ± 0.084 ± 0.02 \% • Expected non-DSXe+: 20 events inside Eextra < 0.4 GeV forgeneric MC ; 1~2 events inside Eextra < 0.4 GeV for data • the branching fraction equal to (1.028±0.05)% • /nfs/cleo3/Offline/rel/20080404_MCGEN_1/data/DECAY.DEC • Decay tau- 0.1778 e- anti-nu_e nu_tau PHOTOS TAULNUNU; • Decay D_s- 0.0599 tau- anti-nu_tau SLN; • total branching fraction = 0.0599 * 0.1778 (sub-decay branching fraction) = 1.065% Difference = 0.74σ (3.5 %)

  18. Group Meeting Chun-Min Jen Generic MC (New 18.9x data)–B.R.measurement NDTgen.MC = 8399.8±101.8 New Signal MC_Exp48+Exp41

  19. Group Meeting Chun-Min Jen III : Determine K+/p+ fake to e+ rate from wrong-side of D(-)s • Apply the same selection criteria on the determination of K+/p+ fake to e+ rate as we did for D+s ee ; we substitute EID<0.8 for EID>0.8, where EID includes information of L(RICH), L(E/P), and L(dE/dX). • In the signal side for D+s ee rather than the single- tag side, we require every charged track, composed of K± or p±, should pass “GoodTrack”, “KaonOK” and “PionOK”. • Process the whole data sets and the total amount of generic MC samples (~18.9x data) • Count the total number of K+ and p+ and then multiply the fake rate measured by Chul-Su Park. (CBX- May 19th, 2008) I think I did something wrong ……. The outcome doesn’t make sense. Stupid!

  20. Group Meeting Chun-Min Jen Electron Momentum Distribution w/ KID & PID selection criteria neither K nor p Data neither K nor p Generic MC

  21. Table IV.Refer to Chul-Su Park’s CBX Data K± fake to e+ rate from wrong-side of D(-)S

  22. Table V.Refer to Chul-Su Park’s CBXGeneric MC K± fake to e+ rate from wrong-side of D(-)S

  23. Group Meeting Chun-Min Jen IV : Inclusive D+S X e+neOur New Plan g • Apply different selection criteria on the determination of K+/p+ fake to e+ rate from what we did for D+s ee . • we require every charged track, composed of e± or K± or p±, should pass “ GoodTrack”, “KaonOK” and “PionOK”. • we didn’t require the final state be *only* one charged track; instead, we allow more than one charged track appeared as our final states. • Only those signal charged tracks within the signal and sideband regions of single-tags are dumped into n-tuples as raw data. • We didn’t exclude those charged tracks with the same charge-sign as that of the mother of single-tags, DS • Signal single track's momentum > 0.2 GeV • |COS θe| < 0.8 for signal single charged track • We store lots of info. Into our n-tuples. p0 g K±/p± from wrong/right-sign DS may fake into e+ D+S D*±S g D±S D-S e+ e- ne Ec.o.m.= 4170 MeV D-/+S D-S p- K+ e+ t+ p+ D+S e- K- nt n Sometimes, don’t believe your eyes.

  24. Group Meeting Chun-Min Jen Electron Momentum Distribution in Generic MCw/ EID & KID & PID & wrong - /right - sign of Dsselection criteria (positive charged-tracks) p+ -> e+ neither K+ or e+ or p+ wrong-sign DS typo! neither K+ or e+ or p+ p+ -> e+ right-sign DS

  25. Group Meeting Chun-Min Jen Electron Momentum Distribution in Generic MCw/ EID & KID & PID & wrong - /right - sign of Dsselection criteria (negative charged-tracks) p- -> e- neither K+ or e+ or p+ wrong-sign DS neither K+ or e+ or p+ p- -> e- right-sign DS

  26. Group Meeting Chun-Min Jen Electron Momentum Distribution in Dataw/ EID & KID & PID & wrong/right side of Dsselection criteria (positive charged-tracks) p+ -> e+ neither K+ or e+ or p+ wrong-sign DS neither K+ or e+ or p+ p+ -> e+ right-sign DS

  27. Group Meeting Chun-Min Jen Electron Momentum Distribution in Dataw/ EID & KID & PID & wrong/right side of Dsselection criteria (negative charged-tracks) p- -> e- neither K+ or e+ or p+ wrong-sign DS neither K+ or e+ or p+ p- -> e- right-sign DS

  28. Group Meeting Chun-Min Jen Comparison of Electron Momentum Distribution b/w data and generic MC • A couple of things I would like to do right now, as I want to see how the outcomes • look like. I refer to Chul-Su Park’s CBX_0732: • Comparison of signal electron candidates from right-sign and wrong sign in real data (FIG.18) • Comparison ofcharged-tracks’ momentum distributions from signal single e , p, and K in generic MC. (FIG.20) • Comparison of charged-tracks’ momentum distributions from signal single e, p , K in generic MC and real data. (FIG.21, FIG.22, FIG.23)

  29. Group Meeting Chun-Min Jen Future Plan … • start the branching fraction measurement for inclusive D+S X e+ne

  30. Backup Group Meeting Chun-Min Jen

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