1 / 31

UIUC – HEP: CLEO Task

UIUC – HEP: CLEO Task. m 2 ( p + p 0 ) (GeV 2 ) . m 2 ( p + p - ) (GeV 2 ) . Mats Selen Aug 5, 2004. Involvement in CLEO-c: CLEO Spokesman : Mats (with David Cassel) CLEO Run Manager : Topher Trigger Hardware : Topher, Norm, Paras Physics (of course) : Everyone

warner
Télécharger la présentation

UIUC – HEP: CLEO Task

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UIUC – HEP: CLEO Task m2(p+p0) (GeV2) m2(p+p-) (GeV2) Mats Selen Aug 5, 2004

  2. Involvement in CLEO-c: • CLEO Spokesman : Mats (with David Cassel) • CLEO Run Manager : Topher • Trigger Hardware : Topher, Norm, Paras • Physics (of course) : Everyone • Analyses: • DS (BR, double partial recon) : Jeremy (GG - finished) • D0K-en (Mixing Analysis) : Chris (MS - finishing) • D0KS00 (BR & Dalitz Analysis) : Norm, Bob, Topher, Mats • D0K+K-0 (BR & Dalitz Analysis) : Paras, Bob (MS) • D0+-0 (Dalitz Analysis) : Charles (MS – finished*) • New UIUC Involvement: Jim Wiss & Doris Kim • Expertise in Dalitz analyses and SL decays • Already involved with several analysis • Very interested in D  Ke (more later)

  3. Mixer/Shaper Crates (24) Drift Chamber Crates Gates CLEO Mixer/Shaper Boards ctrl. DR3 - TQT G / CAL TILE (16) AXTR(16) AXX(16) Flow control & Gating DFC DAQ ASUM Analog TIM TIM Barrel CC Axial tracker QVME DM/CTL DM/CTL TILE(8) STTR(12) L1D ASUM Stereo tracker Endcap CC QVME TIM DM/CTL Level 1 decision AXPR TRCR CCGL TRCR CC Digital TPRO(4) TIM SURF SURF TPRO(2) DM/CTL TCTL TIM DM/CTL The CLEO-c Trigger

  4. What it Looks Like(all more or less alike to untrained eye)

  5. DSf (Jeremy Williams, GG) CLEO-II.V • Badly measured at present: World average B(DSf) = (3.6 ± 0.9)% • Calibrates other DS decays: Equivalent of D0K-+for D0decays. Some DS branching fractions Some D0 branching fractions

  6. DS  s D0 (1) DS s (K…) BDS* D* Use to find N(D*S) from DS  sD0 (2) (…)  s D0 Use to find N(D*) from BDS* D* Double Partial Reconstruction Approach: N(DS) Need to evaluate N(DS) Look for B0  DS*+ D*- Using the fact that N(D*S) = N(D*) from B DS* D* to relate (1) and (2) and find B(DS)

  7. SignalBackgroundTotal

  8. Preliminary new CLEO results: B(DSf) = (2.45 ± 0.42 ± 0.19)%

  9. D*+  +D0; D0 K- e+ Right Sign Signal (RS) Wrong Sign Signal (WS) D*+  +D0; D0 D0; D0 K+ e- Some other+;D0 K+ e- Example of Wrong Sign Background D0 Ke (Mixing) Chris Sedlack & MS CLEO-II.V Hard part: Telling WS signal from background Chris’ solution: Neural Net looking at a variety of kinematic vars.

  10. Training & Evaluating the Nets: WS Background WS Signal r r

  11. Fit for mixed & unmixed yields using proper lifetime distribution: Get signal and background shapes from MC. RMIX = 1.1 ± 0.76 % Example fit of partial data sample Studying cuts & systematics beforeopening the box on rest of data

  12. K*(890) + K0(1430) + f0 + NR K*(890) + K0(1430) + f0 + NR + s 0 1 2 0 1 2 m2(p0p0) (GeV2) m2(p0p0) (GeV2) S/(S+B) ~ 70% S ~ 700 D0 Ks00 Dalitz(Norm, BIE & MS) CLEO-II.V+III m2(p0p0) (GeV2) • Complement KSp-p+ analyses • Good place to search for low mass pp • No r00 to get in the way! • Norm re-writing code • Switching to CLEO-c data m2(KSp0)RS (GeV2) Lots more workto do !

  13. a Vtd Vtb* Vud Vub* g b Vcd Vcb* D0K-K+0 Dalitz (Paras Naik, BIE & MS) CLEO-III • New method for measuring CKM phase g by looking at B– → D0 K–, where D0 → K* K. • Phys.Rev. D67 (2003) 071301, Grossman, Ligeti, & Soffer • Needs a measurement of the strong phase difference dD between D0 → K*+ K– and D0 → K*– K+. • D0 → K+K–p0is a great place to measure dD via interference! • Phys.Rev. D68 (2003) 054010, Rosner & Suprun • Dalitz analysis - Resonant substructure • Previous D0 → K+K–p0 branching ratio measurement (CLEO II) can be revisited. B(D0Þ K+K–p0) = (0.14 ± 0.04)% CLEO II result / PDG Value, 151 ± 42 events, 2.7 fb-1 Phys.Rev. D54 (1996) 4211, Asner, et al.

  14. Both D0’s and D0’s plotted “K+” is really K- for a D0,etc… Data and Dalitz Plot CLEO III ¡(4S) Region: 8.965/fb Dominant resonances: K*± (892 MeV/c2) f(1019 MeV/c2) D*+ → p+ D0 → K+ K–p0 → gg DATA 726 points DATA K±Kmp0 signal region (after selection criteria) mK+p02 (GeV/c2)2 Signal Fraction » 77.4% Signal Events »565 (in the signal region) f K*+ K*- mK-p02 (GeV/c2)2 mK+K-p0 (GeV/c2)

  15. mK+K-2 (GeV/c2)2 f K*+ Dalitz Fit Projections mK+p02 (GeV/c2)2 DATA K*- mK-p02 (GeV/c2)2

  16. CLEO III Dalitz Plot Fit Preliminary!!! Errors only from fit statistics Just when things were humming along… - disk crash- still recovering, taking opportunity to rewrite much of analysis code (i.e. make it better etc).

  17. 0 1 2 3 m2(p+p0) (GeV2) D0-+0(Charles Plager) S/(S+B) ~ 80% S ~ 1100 ** PRD in the works ** CLEO-II.V m2(p+p0) (GeV2) No contribution from s(500) at ~1% level m2(p+p-) (GeV2) 0 1 2 3 0 1 2 3 m2(p+p-) (GeV2) m2(p-p0) (GeV2)

  18. The Future of Charm Physics: CLEO-c CLEO-c y(3770) – 3 fb-1 30 million DD events, 6 million tagged D decays (310 times MARK III) Underway ! MeV – 3 fb-1 1.5 million DsDs events, 0.3 million tagged Ds decays (480 times MARK III, 130 times BES) y(3100), 1 fb-1 & y(3686) ~1 Billion J/y decays (170 times MARK III, 20 times BES II)

  19. What’s new ? CLEO-c

  20. The Future of Charm Physics: CLEO-c Heavy Flavor Physics: “overcome QCD roadblock” • CLEO-c: precision charm absolute Br measurements Leptonic decays  decay constants Semileptonic decays Vcd, Vcs, V_CKM unitarity check, form factors Absolute D Br’s normalize B physics Test QCD techniques in c sector, apply to b sector  improved Vub, Vcb, Vtd, Vts Physics beyond SM will have nonperturbative sectors • CLEO-c: precise measurements of quarkonia spectroscopy & • decay provide essential data to calibrate theory. Physics beyond SM: where is it? • CLEO-c: D-mixing, charm CPV, charm/tau rare decays.

  21. CLEO-c will soon have 50x more data than this!

  22. K+ K- e- e+ p- p+ Single & Double Tagging:

  23. Absolute D branching ratios (S & D tagging)

  24. Absolute D branching ratios (S & D tagging)

  25. Tagging cleans things SL decays up a lot: De

  26. SL branching fractions with CLEO-c now (57.2 pb-1)

  27. A first analysis for Doris & Jim Studying hadronic physics in charm semileptonic decay • 0.The lack of final state interactions makes semileptonic decay a particularly clean environment for studying hadronic physics. An example is the complicated physics of broad s-wave resonances. • 1. FOCUS was able to observe s-wave interference with the dominant K*(896) channel in D+Kpmn and determine the phase shift near the K* pole but FOCUS did not attempt to measure the variation of s-wave phase with Kp mass because of backgrounds. • How well can Cleo-c follow the s-wave phase and amplitude variation given a yield comparable to FOCUS but with greatly reduced backgrounds? • What can we learn about interference in other 4 body semileptonic decay?

  28. Interference in D+ K* mn F-B asymmetry -15% F-B asymmetry! matches model Focus “K*” signal DataMC K* mn interferes with S- wave Kp and creates a forward-backward asymmetry in the K* decay angle with a mass variationdue to the varying BW phase The S-wave amplitude is about 7% of the (H0) K* BW with a 45o relative phase The same relative phase as LASS

  29. Learning more about the s-wave amplitudes 25 MeV bins const ampLASS amp const ampLASS amp eventsCosV G G Kpi mass M(Kp) Focus was limited to the K* peak region because serious non-charm backgrounds dominate out of this region. There is almost no discrimination between a constant and the expected s-wave amplitude from scattering experiments in the narrow region probed by Focus. The higher Kp mass is where the amplitude variation is most interesting. As the s-wave phase shift passes 900 , the cosV asymmetry should reverse. We need the background free environment of CLEO-c to see this

  30. Related SL physics DataMC From 60 pb-1 CLEO-c • Does s-wave interference occur in decays such as Dren?The FOCUS environment has far too much background to see this • What is the q2 dependence of form factors that describe the coupling to the s-wave piece? This might provide additional LQCD tests.The FOCUS q2 resolution is too poor to resolve this • For that matter-- what is the q2 dependence of the K* helicity amplitudesAll experimentalists have been assuming the spectroscopic pole forms But we know the spectroscopic poles are wrong for DKen A journey of 1000 miles begins with a single step…. Doris and Jim are starting to learn the ropes of doing a CLEO-c analysisDoris is spending about half of her time at Cornell Even a totallyun-cut sample has a beautiful K* signal that is well simulated

  31. Summary • Involvement in CLEO-c: • CLEO Spokesman : Mats (with David Cassel) • CLEO Run Manager : Topher • Trigger Hardware : Topher, Norm, Paras • Physics : Everyone • Analyses: • DS (BR, double partial recon) : Jeremy (GG - finished) • D0K-en (Mixing Analysis) : Chris (MS - finishing) • D0KS00 (BR & Dalitz Analysis) : Norm, Bob, Topher, Mats • D0K+K-0 (BR & Dalitz Analysis) : Paras, Bob (MS) • D0+-0 (Dalitz Analysis) : Charles (MS – finished*) • New UIUC Involvement: Jim Wiss & Doris Kim Future looks great!

More Related