Babar: risultati e prospettive Concezio Bozzi, INFN Ferrara - 18 Settembre 2006

Physics reach of BaBar Data Just about any physics that is accessible at Charm Physics Tau physics Continuum e + e -  hadrons ISR: e + e -  hadrons from threshold to ~5 GeV CP Studies with B’s & B Physics e+e- Xe+e- X 2*mB2*mB

354/fb Luminosity Our competitors: 550/fb The challenge: new ideas more channels more sophisticated analyses

ICHEP06 Charm(onium) prod and decay 13 papers Charm(onium) prod and decay 13 papers B to charm decays: 12 papers B to charm decays: 12 papers CP Violation,  : 5 papers CP Violation,  : 5 papers Semileptonic B: 10 papers Semileptonic B: 10 papers Charmless Hadronic B: 19 papers Charmless Hadronic B: 19 papers CP Violation  : 8 papers CP Violation  : 8 papers CP Violation,  : 14 papers CP Violation,  : 14 papers Tau and low-energy: 8 papers Tau and low-energy: 8 papers Charm(onium) spectroscopy: 16 papers Charm(onium) spectroscopy: 16 papers Radiative and leptonic B decays: 12 papers

ICHEP contributed papers! –69 in 2005, 72 in 2004 –70 submitted to journals –44 conference papers Two plenary talks 24 parallel talks in 6 different sessions All updates are on 345 fb -1 (315 onpeak) –Up to June 1 st Belle submitted 28 papers only

Paper luminosity Since Sep. 1 st 2005: BaBar: 70 Belle 28

Non B physics (1/3) Charm(onium) prod and decay 13 papers Charm(onium) prod and decay 13 papers B to charm decays: 12 papers B to charm decays: 12 papers CP Violation,  : 5 papers CP Violation,  : 5 papers Semileptonic B: 10 papers Semileptonic B: 10 papers Charmless Hadronic B: 19 papers Charmless Hadronic B: 19 papers CP Violation  : 8 papers CP Violation  : 8 papers CP Violation,  : 14 papers CP Violation,  : 14 papers Tau and low-energy: 8 papers Tau and low-energy: 8 papers Charm(onium) spectroscopy: 16 papers Charm(onium) spectroscopy: 16 papers Reviewed in Radiative and leptonic B decays: 12 papers

Observables: CP even state: width  , mass  m 1 ; CP odd state: width  , mass  m 2 y =    -        x = (m 1 – m 2 ) /  =  m /  highly suppressed in SM - a powerful window for NP searches Belle has another “2  ” effect in D  K   Close to observation? D 0 -D 0 mixing Sub to PRL, hep-ex/

Keep finding New Charm Meson and Baryon states!  c *  c 0  Charm spectroscopy First observation of a new excited charm baryon  c *  c 0  Last missing L=0 single charm baryon New candidate at 2860 MeV in m(DK), 3 modes Resonance at ~2690MeV? Properties of D sJ (2860)? Sub. PRL, hep-ex/ Sub. PRL, hep-ex/

FCNC in D decays Standard Model: BF(D  X u l + l - ) = O(10 -8 ) R-parity violating SUSY : BF(D  X u l + l - ) ≤ O(10 -5 ) BABAR uniquely measures all D->Xll’ modes. Most limits are better than previous results CLEO-c is The competitor hep-ex/

Y(4260) new excitement Search for e+e-  Y(4260)  ISR Y   (2S)   (2S)  J/  The broad Y(4260) does not show up Hints of something close to the “second peak” BABAR PUB/06-038, submitted to PRL

e + e - from threshold to ~5 GeV Determination of R, goes into calculation of muon g-2. e + e   pp,        2   2    K + K -      2K + 2K-, 3   3    2   2        K + K - 2   2   K + K     K + K       f 0  Initial State Radiation New structure m~2.175 GeV,  ~60-80 MeV, J PC =1 -- “Strange” partner of Y(4260) with c- quark replaced by s-quark? ssss-state? Hadrons BABAR PUB/06-056, to be sub. to PRL

Charm(onium) prod and decay 13 papers Charm(onium) prod and decay 13 papers B to charm decays: 12 papers B to charm decays: 12 papers CP Violation,  : 5 papers CP Violation,  : 5 papers Semileptonic B: 10 papers Semileptonic B: 10 papers Charmless Hadronic B: 19 papers Charmless Hadronic B: 19 papers CP Violation  : 8 papers CP Violation  : 8 papers CP Violation,  : 14 papers CP Violation,  : 14 papers Tau and low-energy: 8 papers Tau and low-energy: 8 papers Charm(onium) spectroscopy: 16 papers Charm(onium) spectroscopy: 16 papers Reviewed in 3_10p20_Kowalewski.pdf CKM Physics (1/3) Radiative and leptonic B decays: 12 papers

UT Roadmap          |V ud V ub | * |V cd V cb | * |V td V tb | * |V cd V cb | * Interference between mixing and decay BB mixing,b→d  /b→s  Time-dependent measurements Time-independent measurements Loops (might be) involved New physics Tree level processes SM only Interference between b→u and b→c Charm(less) Semileptonic decays

Belle has only updated J/  K 0 without publication yet Repeated standard set of measurements Bread and butter… 2.5  direct CPV in CP=-1 modes hep-ex/

sin2  eff -sin2  How well do we know  S f within the SM?  S f = sin2  eff -sin2  S f ~ -  cp sin2  SM: Measure  S f =-  cp S f – sin2  search for deviation from zero Hunt for new physics sin2  with penguin-dominated modes NP: S f ~ -  cp sin2 

sin2  in B   ’K: 4.9  from 0 hep-ex/

D-K+,DS-K+D-K+,DS-K+  c0 K 0 K0K0 f 0 (980)K 0 X 0 (1550)K 0 Non- reson ant toy Dalitz plot BK+K-K0BK+K-K0 75% of B  KKK 0 is not B   K s –Important to understand the underlying background and its interference Full time-dependent Dalitz analysis performed –Knowledge of strong phase and interference between CP-even and CP-odd components allows to extract weak phases without ambiguities Assuming SM (i.e. same weak phase for all final states) –  =0.38±0.08 rad [SM=0.35]  very good agreement with SM –ambiguity on  resolved at the 4  level (SM favored) First ambiguity free measurement of  in b  s penguins Twice more sensitive than Belle in B  Dh 0 hep-ex/

BKSKSBKSKS Old Result: First TD analysis in b  d penguins No report from Belle

b  s summary Naïve average of all b  s modes sin2  eff = 0.52 ±  deviation between penguin and tree (b  s) (b  c) Naïve average of all b  s modes sin2  eff = 0.52 ±  deviation between penguin and tree (b  s) (b  c) Belle : 535M BB BaBar: 347M BB BaBar still exploits its luminosity significantly better than Belle Larger BaBar errors because of full Dalitz 4.9  from 0 New result not yet in averages (more work needed)

Standard penguin (bird), or something else (rabbit may be) ? More statistics crucial for mode-by-mode studies Hazumi, ICHEP06

The (long) way to  M. Gronau, D. London, Phys. Rev. Lett. 65, 3381 (1990) Penguin Tree B->          sets the scale of the  correction Grossmann-Quinn

 update 0000 N  0  0 = 140 ± 25 C  0  0 = −0.33 ± 0.36 ± 0.08 Br  0  0 = (1.48 ± 0.26 ± 0.12)  10 −6 B 0 tags _ asymmetry S  = −0.53 ± 0.14 ± 0.02 C  = −0.16 ± 0.11 ±  evidence of CPV hep-ex/

2.3  diff. btw. Belle and BaBar ( C =  A ) Comparison with Belle’s 

ΔΕΔΕ m ES 0f00f0 0000 It was unbelievably good… Error on  from B→  dominated by B→     limit:  (  from 11 o to 18 o First evidence of B→     N  0  0 = ± 22 −31 Br  0  0 = ( ± 0.27)  10 −6 −0.36 hep-ex/ Belle: no news, never presented a result 3.0  significance

Religious wars… Direct measurements Indirect meas.

B -  (D  f)K- f=common to D0 & anti D0 f=D CP (Gronau-London-Wyler)(GLW method) (small asymmetry) f=DCSD (Atwood-Duniets-Soni)(ADS Method) (additional problem of  D ) f= Dalitz analysis of D0-> K s      (GGSZ) (combines features of GLW & ADS depending on the location in Dalitz plot)- the dominant method [Giri, Grossman, Soffer, & Zupan, PRD 68, (2003), Bondar (Belle), PRD 70, (2004 )] Solve for  & ,      – r B =(|A 1 |/ |A 2 |)  no golden channel +

Interference gets smaller! Dalitz analysis update Errors shrink (in particular systematics), but r B is smaller  error on  increases … (was 70±31 ± ± ) No update from Belle hep-ex/

u V ub |V ub | measurements TaggedUntagged Inclusive Exclusive mXmX m 2 m ES ElEl

b  ul exclusive: probing theory New “loose cuts method” 4 more results on V ub and 2 on V cb Old technique, 80 fb-1

Inclusive channels ~7% measurement now Exclusive channels Aiming for 5% accuracy Must resolve exclusive & inclusive discrepancy Measurements B-Factories

“There is a tension…”

Prospects in the “1/ab” phase (~ +1/ab from Ble) Aiming for: Also counting on improved systematics in most areas & help from the theory side Now ~7% ~30 ° ~18 ° ~0.04 r B =0.1

Other B decays (1/3) Radiative and leptonic B decays: 12 papers Charm(onium) prod and decay 13 papers Charm(onium) prod and decay 13 papers B to charm decays: 12 papers B to charm decays: 12 papers CP Violation,  : 5 papers CP Violation,  : 5 papers Semileptonic B: 10 papers Semileptonic B: 10 papers Charmless Hadronic B: 19 papers Charmless Hadronic B: 19 papers CP Violation  : 8 papers CP Violation  : 8 papers CP Violation,  : 14 papers CP Violation,  : 14 papers Tau and low-energy: 8 papers Tau and low-energy: 8 papers Charm(onium) spectroscopy: 16 papers Charm(onium) spectroscopy: 16 papers Reviewed in

B→  : easy to interpret New physics: Replace W + by H + E Extra Signal MC hep-ex/ Sensitivity nearly at SM expectation Additional hadronic B decay tagged sample New BABAR result: 320M BB events, Tagged with B  DXl decays E Extra Data + 1.3σ

B   : a year of emotions April: Belle announces at FPCP a >4  evidence for B   May-July: BaBar struggles to reproduce the accuracy of Belle (in an area where we were traditionally more advanced) August: –BaBar presents only one of the two independent analyses while still investigating –Belle presents an errata of the efficiencies by a factor 2!!!! Significance down to 3.5 , BF a factor 2 larger BaBar and Belle have similar accuracies Soon: BaBar is ready to publish both analyses  expect an error which is 40% smaller than Belle’s

Impact on new physics Limits on e.g. 2 Higgs doublet model SM prediction enhanced/reduced by factor r H Or: Within the SM, use the value of BF(B +  +  ) to give a measurement of f B W.S.Hou, PRD 48, 2342 (1993)

Radiative B decays FCNC process suppressed in SM: sensitive to new particles in loops b  s  : Inclusive and many exclusive measurements b  sl + l - : More information from kinematics b  d  : strongly suppressed but open to different physics b  d l + l - : on the way

Observation of b  d  decays: B   First observation of B   +  Good agreement with predictions based on Standard Model amplitudes B +  +  B 0  0  No update from Belle hep-ex/

B →  ICHEP’06 : |V td /V ts |  m s and B  (  )  : same kind of CKM constraint from independent processes! Form factor ratio 1/  = 1.17±0.09 Annihilation amplitude corrections  R = 0.1±0.1

FCNC: B  K(*)ll Rarest B decays yet observed New analysis adds measurements of decay kinematics B  Kll (46 events) B  K*ll (57 events) PRD 73, (2006)

Forward-backward asymmetry Theoretical uncertainty on kinematics generally smaller than on branching fraction Beyond SM particles in loops may have dramatic effect on short distance physics – flip sign of A FB ? Theoretical curves Experimental results PRD 73, (2006)

BaBar is entering in its “1/ab” phase. Expected major outcomes are:  Precision knowledge of the flavor sector of the SM  Measurements of CP violation and decay properties in penguin-dominated decay modes  Measurements of rare decays in charm and tau physics  Advances in hadronic physics With the possiblity to reveal deviations from the SM [If we continue to see no deviation at these precisions, the results will serve as major constraints on the flavor structure of New Physics to be seen at LHC.] Summary

“See your tax dollars at work!” At ICHEP’06 BaBar has achieved record productivity, overwhelming the direct competitor In the topics where the luminosity matters the refined statistical analysis technique makes BaBar competitive even with 35% less luminosity (345 M BB/547 M BB) Showed dominance in several areas such as: –CPV in b  s penguins New modes –Measurements related to  First observation of B      –Dalitz Time Dependent analyses First full analysis of B  KKK 0 (including  K 0 ) –D-mixing in multibody D decays Innovative technique to exploit also these decay modes –Leptonic B Decays After Belle corrected a mistake in their efficiencies, we have a measurement of BF(B   ) with same accuracy as them and potentially 40% better by fall –Semileptonic B decays, –Charm and Charmonium spectroscopy

° o ° ° ° ° ° ° ° ° ° ° D 0 -D 0 mixing, Exclusive V ub TD analyses and BF of charmless decays (  K S,  K/ ,  ’K S,  ’ ,  ’ ,  ' K L, a 1  ), B → K η ( ' ) γ charmonium (convener, B  cc  hadrons, B  cc[h C  ]K), t  m K S bottomonium, t  mg Rad. Pen. convener,  (DK GLW&Dalitz), inclusive b → s , B → D* ,  lifetime,  →  K s,  → K s  0 Physics Analysis Coordinator, sin2  in cc, sin(2  +  ) D , 3-body D Dalitz, D 0 -D 0 mixing,  (DK ADS & Dalitz), sin2  (  ),  K, KK, sin2  (TD and BF of  K, , KKK), exclusive V ub, B → ll sin2  (B → D 0(*) h 0 ), V cb (B → D * l ), B   SL convener V cb (B → D * l ), B lifetime & mixing, CPV in mixing, t  mg, D 0 →K   weak annihilation inclusive V ub, V cb (B → D * l ), charmonium, bottomomium,   DK ADS),  charmless 3-body (K ) sin2  in cc, CPV in mixing sin2  &B reco conveners, sin2  ( B  D*D*), ISR,  (DK GLW & Dalitz) B →  with hadronic tags 3-body D Dalitz, light meson spectroscopy, D sJ *, exotics,D (s) (*) D (s) (*) Babar Italia postcards

backup

  in  and 3  modes Limit 1.6 x10 90% CL (BaBar) 0.65 x10 90% from Belle MSSM prediction BSM VI Hayasaka Tan  M A (GeV/c 2 )

Several ways to measure sin2  Increasing tree diagram amplitude Increasing sensitivity to new physics in CP measurements

Evolution of sin2  measurements Present CKM fit Present WA BaBar 2006: 0.715±0.034

Combination with Belle Measurements are consistent [2.1  in the case of C CP ] and the averages consistent with the SM. Still to work to make the samples uniform (J/  K 0 vs all modes)

Update of      –S=-0.19±0.21 –C=-0.07±0.15   eff =(96+7-6) o [was ] –f L =0.977±0.024  A= / / S=0.01+/-0.12+/-0.03 C=0.154+/ / nowwas A= / / S=-0.10+/-0.14+/-0.04 C=0.34+/-0.11+/-0.05 Direct CPV now at 3 sigma

BABAR + Belle constraints on  from direct measurements Error on  depends crucially on value of r B Combined direct constraint:  = (78 +/- 30) o From the Dalitz Analysis alone:  =(92+/- 41  11 +/- 12 ) o (BaBar) φ3=53°  3°  9°) Belle The method highly sensitive to r B : fits favor r B ~ 0.1 (BaBar) ; r B >0.2 (Belle). Main cause of the difference in errors Error due to uncertainties in treatment of the D  K s  -Dalitz plot (amplitudes and phases) -CLEO-c data can help. Projected error 3-5 deg

Recent results on:     e    L&FV)    h highly suppressed in SM C.L BaBar: Br(    x10 -7 Br(   e  x10 -7 Belle: Br(    x10 -7 Br(   e  x10 -7 Lepton Flavor Violation in  decays Example of how it impacts

Measurement of  Update of B  D0K [Dalitz] B+B+ B-B- B+B+ B-B- B  DK BD*KBD*K DK(old)DK(new)D*K(old)D*K(new) x-0.08±0.07± ±0.059± ±0.09± ±0.091±0.020 y-0.06±0.09± ±0.071± ±0.11± ±0.096±0.022 X+-0.13±0.09± ±0.056± ±0.09± ±0.088±0.015 Y+0.02±0.08± ±0.066± ±0.12± ±0.111±0.032 Errors shrink (in particular systematics), but rB is smaller (x,y closer to 0)  error on  increases …  = 92 +/- 41 +/-10 +/- 16 (was 70+/ )

Updated B   +   results B 0 tags _ asymmetry f L (B 0 →  +  − ) = ± −0.013 S long = −0.19 ± −0.07 Br  +  − = (23.5 ± 2.2 ± 4.1)  10 −6 C long = −0.07 ± 0.15 ± 0.06 hep-ex/