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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)1 B → K S 0 0 B → K S K S B → K S 0 B → D *+ D *- B → a 1 , a 1 K, b 1 , b 1 K... (4S) → B CP B CP Measurements of φ 1 and φ 2 Tagir Aushev For the Belle Collaboration (EPFL, Lausanne ITEP, Moscow)
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)2 relative magnitudes CKM matrix & unitary triangle
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)3 CP Violation in the Standard Model Triangle is well measured φ 1 ( ) mainly from B 0 → J/Ψ K S “golden mode” Smaller and smaller room for the vertex position, but it is still in New decay modes are examining to find a New Physics
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)4 TCPV measurement on B-factory B’s are produced in a boosted frame t is measured from vertex positions B’s are entangled flavor of B 1 at time t 2 is determined by B 2 decay
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)5 8GeV (e - ) 3.5GeV (e+) Silicon Vertex Tracker 5-layer, double-sided strips Drift Chamber 40-layer, small cell DIRC (PID) quartz Cherenkov detector EM Calorimeter CsI crystals Flux Return RPC and LST instrumented iron 1.5 T Solenoid Belle & BaBar B-factories
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)6 BaBar collected 510 fb -1 Current luminosities
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)7 B D (0,+) D 0 After evidence for DCPV in B D - D + recently shown by Belle all B DD decays has a special interest B.R. and charge asym for B D + D 0 were updated by Belle: B.R. = (3.85 ± 0.31 ± 0.38)·10 -4 BaBar’06: (3.8 ± 0.6 ± 0.5)·10 -4 A = 0.00 ± 0.08 ± 0.02 BaBar’06: -0.13 ± 0.14 ± 0.02 Also an upper limit for B D 0 D 0 : B.R.<0.43·10 -4 @90%C.L. hep-ex/0802.2988
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)8 TCPV in B 0 D* + D* – B 0 D* + D* – is b ccd transition and so sensitive to sin2 just like the “Golden” B 0 cc K 0 making it an important check Series of papers were published by Belle and BaBar Recently the results are updated with latest statistics Belle result is the first time presented Belle Preliminary N=545 +- 29 Phys.Rev.D76:111102,2007
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)9 BaBar: R = 0.143 0.034 0.008 Belle: R = 0.116 0.042 0.004 Since it is a decay of S VV CP- eigenstate depends on angular momentum of the VV system: Separating the CP-odd fraction, R , is done via a 1D angular analysis Helicity of B 0 D *+ D *– Belle Preliminary
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)10 TCPV in B 0 D *+ D *– S=-sin2 1 A=-C BaBar-0.66 ± 0.19 ± 0.04+0.02 ± 0.11 ± 0.02 Belle-0.93 ± 0.24 ± 0.15+0.16 ± 0.13 ± 0.02 Belle Preliminary
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)11 Penguin dominated B decays are sensitive to NP + New Physics may introduces extra CP phase in the decay Deviation of Time-dependent CP violation parameters from the SM expectation Hint of New Physics Searches for a New Physics SM s,d q NP s,d q
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)12 TCPV in B 0 → K S 0 0 : b s qq N sig = 307±32 Belle +0.43+/-0.49+/-0.09 BaBar +0.72+/-0.71+/-0.08 Average+0.52+/-0.41 Belle -0.17+/-0.24+/-0.06 BaBar -0.23+/-0.52+/-0.13 Average -0.18+/-0.22 LR>0.9, good tag X SM expectation >2 from the SM Phys.Rev.D76:071101,2007 Belle Preliminary S=-sin2 1 A=-C
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)13 TCPV in B 0 → K S π 0 N sig = 459 ± 29 B.R.= (10.3±0.7±0.6)·10 -6 Belle +0.33+/-0.35+/-0.08 BaBar +0.40+/-0.23+/-0.03 Belle -0.05+/-0.14+/-0.05 BaBar -0.24+/-0.15+/-0.03 S=sin2 1 A=-C Phys.Rev.D77:012003,2008 Phys.Rev.D76:091103,2007
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)14 ~90 o ±10 o Measurements of φ 2 was measured in and systems The same matrix elements are also involved to the B decays to axial vectors a 1, b 1 … Some of them can be used only with much larger statistics
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)15 Measurement B a 1 First time-dep CP asymmetry in B → a 1 + PRL 98, 181803 (2007) BaBar 608 ± 53 B 0 →a 1 (461 ± 53 flav.-tagged) Belle Preliminary
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)16 B→00B→00 Latest result from Belle:
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)17 B decays to light mesons B→b 1 0 π + : (6.7±1.7±1.0)·10 -6 B→a 1 0 π + : (20.4±4.7±3.4)·10 -6 B→b 1 0 K + : (9.1±1.7±1.0)·10 -6 B→a 1 + K 0 : (34.9±5.0±4.4)·10 -6 B→b 1 - π + : (10.9±1.2±0.9)·10 -6 B→a 1 - π 0 : (13.2±2.7±2.1)·10 -6 B→b 1 - K + : (7.4±1.0±1.0)·10 -6 B→a 1 - K + : (16.3±2.9±2.3)·10 -6 No charge asym’s found PRL 99:261801, 2007 PRL 100:051803, 2008 PRL 99:241803, 2007
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)18 CP Violating Decays of the (4S) CP violation !! J/ K S 1 1 J/ K S 2 1 CP 1 CP 1 J/ K L 1 1 J/ K L 2 1 CP 1 Y(4S) CP 1 J/ K S 1 1 C K S C1 K S (2S)K S 2 1 CP 1 B0B0 B0B0 _
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)19 Partial reconstruction Full reconstruction ++ -- KSKS J/ ++ -- ++ -- J/ c KSKS Signal MC J/ (l l )K S J/ (any)K S Y (4S) _ B0B0 B0B0 About 40 times higher eff. than full reconstruction method 1.1(0.6) inclusive-J/ ( c ) events in 535 million Y(4S) decays
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)20 N sig =-1.5 -2.8 events +3.6 Br( Y(4S) B 0 B 0 J/ K S +J/ ( c )K S ) 4x10 7 (90%C.L.) SM prediction : 1.4x10 -7 Results with 535M Y (4S) decays Control sample B D (*)- and D *- B 0 c K S and J/ K S Nsig=35 ±16 events B 0 J/ K S B 0 J/ ( c ) K S With 30 billion Y(4S) (30ab -1 ), such decays will be observed with 5 significance
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Moriond EW, 3 Mar 2008Tagir Aushev (EPFL, ITEP)21 Summary CP violations was measured in various B decays –Both mixing-induced & direct CPV observed Excellent agreement with Standard Model –Small room for New Physics remains in flavour sector Next order of the statistics is needed to give an answer for the New Physics existence
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