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Motivation Fit Method Inputs Results Conclusion
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen2 MOTIVATION In the hunt for New Physics (Supersymmetry) the Standard Model (SM) has to be scrutinized in various areas Two very promising areas are CP violation and rare decays, that may reveal first signs of New Physics before the start of LHC BABAR/Belle have measured different CP asymmetries e.g. sin 2 ( K s ) = 0.736±0.049, sin 2 ( K s ) = -0.14±0.33 sin 2 ( ) = -0.58±0.2 with present statistics this is in good agreement with SM prediction that CP violation is due to phase of CKM matrix The phase of the CKM matrix, however, cannot predict the observed baryon-photons ratio: n B /n g 10 -20 n B /n g 10 -11 9 orders of magnitude difference There are new phases predicted in extension of SM For example in MSSM 124 new parameters enter of which 44 are new phases
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen3 The Cabbibo-Kobayashi-Maskawa Matrix A convenient representation of the CKM matrix is the small-angle Wolfenstein approximation to order O( 6 ) The unitarity relation that represents a triangle (called Unitarity Triangle) in the - plane involves all 4 independent CKM parameters, A, , and =sin c =0.22 is best-measured parameter (1.5%), A .8 (~5%) while - are poorly known with and
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen4 MOTIVATION SM tests in the CP sector are conducted by performing maximum likelihood fits of the unitarity triangle CKM tests need to be based on a conservative, robust method with a realistic treatment of uncertainties to reduce the sensitivity to avoid fake conflicts or fluctuations significant conflict Only then we can believe that any observed significant conflict is real indicating the presence of New Physics Present inputs are based on measurements of B semi- leptonic decays, m d, m s, a cp ( K S ) & | K | to extract Though many measurements are rather precise already the precision of the UT is limited by non gaussian errors in theoretical quantities th (b u,cl ), B K, f B B B,
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen5 Global Fit Methods Different approaches exist: The scanning method a frequentist approach first developed for the BABAR physics book (M. Schune, S. Plaszynski), extended by Dubois-Felsmann et al RFIT, a frequentist approach that maps out the theoretical parameter space in a single fit A.Höcker et al, Eur.Phys.J. C21, 225 (2001) The Bayesian approach that adds experimental & theoretical errors in quadrature M. Ciuchini et al, JHEP 0107, 013 (2001) A frequentist approach by Dresden group K. Schubert and R. Nogowski The PDG approach F. Gilman, K. Kleinknecht and D. Renker
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen6 New Physics is expected to affect both B d B d mixing & B s B s mixing introducing new CP-violating phases that differ from SM phase r r This is an extension of the scenario discussed by Y. Nir in the BABAR physics book to B s B s mixing and b sss penguins Y. Okada has discussed similar ideas r r Yossi considered measurements of V ub /V cb, m Bd, a Ks, a , we extend this to m Bs, a Ks (a ’Ks ) in addition to K, (DK) r r In the presence of new physics: i) remain primarily tree level ia) remains at penguin level ii) There would be a new contribution to KK mixing constraint: small (ignore new parameters) iii) Unitarity of the 3 family CKM matrix is maintained if there are no new quark generations Model-independent Analysis of UT
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen7 Under these circumstances new physics effects can be described by 4 parameters: r d, d, r s, s Our observables are sensitive to r d, d, r s induced by mixing (no s sensitive observable) In addition, we are sensitive to a new phase s ’= s - d in b sss transitions Thus, New Physics parameters modify the parameterization of following observables Model-independent Analysis of UT
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen8 The Scanning Method The scanning method is an unbiased, conservative approach to extract & New Physics parameters from the observables We have extended the method of the BABAR physics book (M.H. Schune and S. Plaszczynski) to deal with the problem of non-Gassian theoretical uncertainties in a consistent way We factorize quantities affected by non-Gaussian uncertainties ( th ) from the measurements We select specific values for the theoretical parameters & perform a maximum likelihood fit using a frequentist approach
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen9 The Scanning Method A particular set of theoretical parameters we call a “model” M & we perform a 2 minimization to determine Here denotes an observable & Y accounts for statistical and systematic error added in quadrature, while F(x) represents the theoretical parameters affected by non-Gaussian errors For Gaussian error part of the theoretical parameters, we also include specific terms in the 2 We fit many individual models scanning over the allowed theoretical parameter space for each of these parameters We consider a model consistent with data, if P( 2 M ) min >5% For these we determine and plot contours The contours of various models are overlayed We can also study correlations among theoretical parameters extending their range far beyond that specified by theorists
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen10 The 2 Function in Model-independent Analysis
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen11 Semileptonic Observables Presently, consider 11 different observables V cb affected by non-Gaussian non-Gaussianuncertainties V ub phase space corrected rate in B D * l extrapolated for w 1 excl: incl: excl: incl: branching fraction at (4S) & Z 0 branching fraction at (4S) branching fraction at (4S) & Z 0
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen12 K 0 K 0 CP-violating & B 0 B 0 -mixing Observables theoretical parameters with large non-Gaussian errors account for correlation of m c in 1 & S 0 (x c ) New Physics scale parameters r d and r s in BB mixing m Bs m Bd KKKK QCD parameters that have small non Gaussian errors (except 1 )
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen13 CP-violating Observables in BB System New Physics phases in BB mixing New phase component in b sss sin 2( + d ) from K S sin 2( + s ) from K S sin 2( - d ) from from D (*) K Note, that presently no extra strong phases in a are included In future will include this adding C in the global fits
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen14 Observables For other masses and lifetimes use PDG 2003 values ObservablePresent Data Set2011 Data Set Y(4S) B(b ul ) [10 -3 ]1.95±0.19 exp ±0.31 th 1.85±0.06 exp LEP B(b ul ) [10 -3 ]1.71±0.48 exp ±0.21 th 1.71±0.48 exp Y(4S) B(b cl )0.1090±0.00230.1050±0.0005 LEP B(b cl )0.1042±0.0026 Y(4S) B(B l ) [10 -3 ]2.68±0.43 exp ±0.5 th 3.29±0.14 |V cb |F(1)0.0367±0.0080.0378±0.00038 m Bd [ps -1 ]0.502±0.0070.502±0.00104 m Bs [ps -1 ] (20±5) 14.4 @90% CL (20±5)25±1 | K | [10 -3 ]2.282±0.017 0.2235±0.0033 sin 2 from K s 0.736±0.0490.736±0.01 sin 2 from K s ( ’K s )-0.14±0.33 (0.27±0.22)0.6±0.15 sin 2 -0.4±0.2-0.4±0.05 sin 0.7±0.50.7±0.15
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen15 Theoretical Parameters ParameterPresent ValueExpected Value in 2011 F D* (1)0.87 0.950.90 0.92 (cl ) [ps -1 ]34.1 41.235.7 39.2 ( l ) [ps -1 ]12.0 22.211.0 13.4 (ul ) [ps -1 ]54.6 80.260.6 76.9 BKBK 0.74 1.0 Bk = 0.060.805 0.935 Bk = 0.03 f Bd B Bd [MeV]218 238 fB BB = 30223 233 fB BB = 10 1.16 1.26 = 0.05 11 1.0 1.64 22 0.564 0.584 33 0.43 0.51 BB 0.54 0.56
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen16 Error Projections for CP Asymmetries 10 -2 10 -1 11010 2 10 -2 10 -1 1.0 2009 Integrated Luminosity [ab -1 ] Error on A CP 2006 PEP-II, KEKB Super B-Factory >2010 sin(2 ) K0SK0SK0SK0S D*D*D*D*D*D*D*D* ’K 0 S, J/ K 0 S now
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen17 Present Status of the Unitarity Triangle in SM Fit central values from individual fits to models Range of - values resulting from fits to different models Contour of individual fit Overlay of 95% CL contours, each represents a “model” SM fit to A, , using present data set
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen18 Present Results ParameterScan Method 0.116-0.335, =± 0.027 0.272-0.411, =± 0.036 A0.80-0.89, =± 0.028 mcmc 1.06-1.29, =± 0.18 (20.7-27.0) 0, =± 7.1 (84.6-117.2) 0, =± 5.4 (40.3-72.5) 0, =± 8.3 0.11 0.020 0.024 0.18 2.6 15.8 3.3
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen19 Present Status of the - Plane Global fits to present extended data set including a Ks, a & (DK) The introduction of new parameters r d, d, r s, & s weakens the sin 2 constraint sin 2 constraint Weakening of m Bd, m Bs & sin 2 bounds is not visible due to large errors & impact of V ub /V cb, K, sin constraints large errors & impact of V ub /V cb, K, sin constraints Negative region is rejected by sin constraint
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen20 Present Status of r d - d Plane & r s /r d - s Plane rdrdrdrd dddd ssss r s /r d Global fits to present extended data set including a Ks, a & (DK) 0.5 0. -0.5 0 1 2.5 1.5 -1.5 0. 0 1 2.5 r d - d plane is consistent with SM SM Second region (r d <1, d <0) is rejected by sin constraint is rejected by sin constraint r s - s plane is consistent with SM for some models SM for some models Second region inconsistent with SM is visible with SM is visible
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen21 Present Status of the - Plane Old global fits to present data set excluding a Ks, a & (DK) fitting only to r d, d fitting only to r d, d The introduction of new parameters r d, d weakens the sin 2 constraint m Bd & m Bs biunds sin 2 constraint m Bd & m Bs biunds Fits extend into negative region
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen22 Present Status of r d - d Plane & r s /r d - s Plane r d - d plane is consistent with SM SM Second region (r d <1, d <0) is visible is visible rdrdrdrd 0.5 0. -0.5 0 dddd 1 Old global fits to present data set excluding a Ks, a & (DK) fitting only to r d, d fitting only to r d, d
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen23 Possible Status of the - Plane in 2011 Global fits to data set expected in 2011 including a Ks, a & (DK) Reduced errors yield smaller-size contours and a reduced # of accepted models of accepted models The sin 2 constraint remains weak, now see also weakening m Bs bound m Bs bound
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen24 Possible Status of r d - d & r s /r d - s Planes in 2011 rdrdrdrd ssss Global fits to data set expected in 2011 including a Ks, a & (DK) 0.5 0. -0.5 0 2.0 0.5 -0.5 0. 0 r s /r d 1 2.0 1 dddd r d - d plane is still consistent with SM with SM Size of contours are reduced substantially substantially r s - s plane now is inconsistent with SM for some models with SM for some models Second region inconsistent with SM disappears with SM disappears
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen25 Comparison of Results ParameterPresent ResultsPossible results in 2011 0.177-0.372, =± 0.022 0.227-0.313, =± 0.013 0.236-0.473, =± 0.025 0.329-0.351, =± 0.007 A0.80-0.89, =± 0.030 0.81-0.88, =± 0.025 mcmc 1.0-1.41, =± 0.16 1.09-1.29, =± 0.08 (17.9-28.6) 0, =± 3.1 (23.1-26.9) 0, =± 1.1 (96.3-123.6) 0, =± 5.0 (101.4-105.1) 0, =± 1.9 (34.4-61.3) 0, =± 4.4 (48.1-55.5) 0, =± 1.5 0.031 0.017 0.035 0.18 1.8 6.4 2.6 0.11 0.006 0.022 0.09 1.1 2.0 1.3 Fit Results for parameterization with r d, d, r s, & s
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen26 Possible Status of the - Plane in 2011 Global fits to data set expected in 2011 including a Ks, a , (DK) & a ’Ks (DK) & a ’Ks Inclusion of a ’Ks results in reduced countours
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen27 Possible Status of r d - d & r s /r d - s Planes in 2011 2.5 0.5 -0.5 0. 0 0.5 0. -0.5 0 r s /r d 1 2.5 1 Global fits to data set expected in 2011 including a Ks, a , (DK) & a ’Ks & a ’Ks rdrdrdrd dddd ssss r d - d plane is still consistent with SM with SM Inclusion of a ’Ks reduces r d - d contour sizes r d - d contour sizes r s - s plane remains inconsistent with SM inconsistent with SM for some models for some models Inclusion of a ’Ks reduces r s /r d - s contour sizes r s /r d - s contour sizes
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen28 Possible Status of the - Plane after 2011 Global fits to data set expected in 2011 including a Ks, a & (DK) with a Ks =-0.96±0.01 & a =-0.95±0.05 with a Ks =-0.96±0.01 & a =-0.95±0.05 Using Belle central values with small errors changes the picture obtain 2 separated regions in - plane obtain 2 separated regions in - plane Weakening of sin 2 , m Bd, m Bs & sin 2 bounds is apparent now
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen29 Possible Status of r d - d & r s /r d - s Planes after 2011 ssss dddd rdrdrdrd 2.0 1.5 -1.5 0. 0 0.5 0. -0.5 0 r s /r d 1 2.0 1 Global fits to data set expected in 2011 including a Ks, a & (DK) with a Ks =-0.96±0.01 & a =-0.95±0.05 with a Ks =-0.96±0.01 & a =-0.95±0.05 r d - d plane is shifted to r d >0, d >0 values r d >0, d >0 values Size of contours are reduced substantially substantially r d - d plane is now inconsistent with SM with SM 2 s >0 regions are favored r s - s plane now is highly inconsistent with SM inconsistent with SM
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Super B-factory workshop Hawaii, 21-01-04G. Eigen, U Bergen30 Conclusions Model-independent analyses will become important in the future The scanning method provides a conservative, robust procedure with a reasonable treatment of non-gaussian theor. uncertainties This allows to avoid fake conflicts or fluctuations significant This is crucial for believing that any observed significant discrepancy discrepancy is real indicating New Physics Due to the large theoretical uncertainties all measurements are presently consistent with the SM expectation Deviation of a CP ( K S ) from a CP ( K S ) is interesting but not yet significant, similar comment holds for Belle’s S & A results If errors get reduced as prognosed, - plane will be substantially reduced in 2011 The fits indicate that the impact of New Physics may be less visible in - plane but show up in r d - d or r s - s planes In the future we will incorporate other sin 2 measurements and add further parameters for strong phases It is useful to include sin(2 + ) from B D (*) modes
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