Measurements of the CKM Angle α at BaBar
|
|
- Stella Nash
- 6 years ago
- Views:
Transcription
1 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 SLAC-PUB-493 Measurements of the CKM Angle α at BaBar S. Stracka on behalf of the BaBar Collaboration Università degli Studi di Milano and INFN, Sezione di Milano - I-33 Milano, Italy We present improved measurements of the branching fractions and CP-asymmetries in the B π + π, B π π, and B + ρ + ρ decays, which impact the determination of α. We find for B ππ decays, and S ππ + =.68 ±. ±.3 C ππ + =.5 ±.8 ±. Cππ =.43 ±.6 ±.5 B(B π π ) = (.83 ±. ±.3) 6 B(B + ρ + ρ ) = (3.7 ±.4 ±.4) 6 f L (ρ + ρ ) =.95 ±.5 ±.6 α ρρ = ( ) for B ρρ decays. The combined branching fractions of B K (7)π and B K (4)π decays are measured for the first time and allow a novel determination of α in the B a (6) ± π decay channel. We obtain B(B K (7) + π + K (4) + π ) = ( ) 5 B(B + K (7) π + + K (4) π + ) = ( ) 5 α a π = (79 ± 7 ± ). These measurements are performed using the final dataset collected by the BaBar detector at the PEP-II B-factory.. Introduction in B a (6) ± π decays. The primary goal of the experiments based at the B factories is to test the Cabibbo-Kobayashi-Maskawa (CKM) picture of CP violation in the standard model of electroweak interactions []. This can be achieved by measuring the angles and sides of the Unitarity Triangle in a redundant way. An effective value α eff for the CKM phase α arg( V td Vtb /V ud V ub ) can be extracted from the timedependent analysis of B meson decays dominated by tree-level b uūd amplitudes, such as B π + π, B ρ + ρ, B ρ ± π, and B a (6) ± π. The current average values of α, α = (9 ± 7) [] and α = ( ) [3], obtained with different statistical techniques, are based solely on the analysis of B ππ, B ρρ, and B ρπ decays. The measurement of the angle α has witnessed significant progress over the past year. The following sections are organized as follows: a brief introduction on the experimental technique is given in Sec. ; the summer 8 update of the measurement of the time-dependent CP-violating asymmetries in B π + π decays and of the branching fractions (BFs) of B π π decays is reported in Sec. 3; Sec. 4 describes the 9 update of the BF measurement of B + ρ + ρ decays, and its impact on the precision of the determination of α; in Sec. 5, we introduce the first measurement of B K (7)π and B K (4)π decays and a new determination of α. Experimental techniques The interference between the direct tree decay (which carries the weak phase γ) and decay after B B mixing (which carries a weak phase β) results in a time-dependent decay-rate asymmetry that is sensitive to the angle β + γ = π α. At the asymmetric-energy e + e B-factory PEP-II, running at a center of momentum (CM) energy of.58 GeV, a B B pair is coherently produced in the decay of a Υ(4S) resonance. The resulting B B system has a boost βγ.56 with respect to the laboratory frame. By means of this experimental device it is possible to measure the decay vertex displacement z of the two B mesons in the event, and hence their proper-time difference t meas z βγc. One of the B mesons (B rec ) is fully reconstructed according to the final state of interest. In order to study the time-dependence of the decay rates, it is necessary to measure the proper-time difference t between the two B mesons in the event and to identify the flavor of the other B-meson (B tag ). The flavor and the decay vertex position of B tag are therefore identified from its decay products. The decay-rate distribution for B ( B ) decays to Work supported in part by US Department of Energy contract DE-AC-76SF55. SLAC National Accelerator Laboratory, Menlo Park, CA 945
2 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 a CP-eigenstate, such as π + π, is given by: dn d t = e t /τ 4τ { q tag [ C cos( m d t) () ]} S sin( m d t), where τ = (.536±.4)ps [4] is the mean B lifetime, m d = (.5 ±.7)ps is the B B mixing frequency [4], and q tag = + ( ) if the B tag decays as a B ( B ). The parameters S and C describe mixinginduced and direct CP-violation, respectively, and are defined as: S = Imλ + λ, C = λ + λ, with λ = q Ā p A, where q/p is related to the B B mixing, and A (Ā) is the amplitude of the decay of a B (B ) to the final state under study. If only the tree amplitude contributes to the decay, S = sin(α) and C =. However, b uūd transitions receive sizeable contributions from penguin (loop) amplitudes, which carry different strong and weak phases. This contribution can result in non-zero direct CP-violation C and modifies S into S = sin(α eff ) C. () The angle α eff coincides with α in the limit of vanishing penguin contributions. In order to constrain α α α eff, techniques based on the SU() isospin symmetry (for decays to a CP-eigenstate, such as B π + π, ρ + ρ ) or the SU(3) approximate flavor symmetry (for decays to a non CP-eigenstate, such as B ρ ± π, a (6) ± π ) have been devised, and are discussed in the remaining of this paper. A neural network based tagging algorithm [5] is used to determine whether the B tag is a B or a B. Events are separated according to the particle content of the B tag final state into events where there are leptons, kaons and pions, for a total of seven mutually exclusive categories. The performance of the tagging algorithm is characterized by the efficiency ǫ tag in the determination of the flavor of B tag and by the mistag probability ω, and depends on the tagging category. The t distribution of Eq. is convolved with a detector resolution function, which differs for signal and background, and is parameterized as a triple Gaussian. Dilution from incorrect assignment of the flavor of B tag is also taken into account: dn d t meas = e t /τ 4τ q tag ( ω) R( t meas t), { q tag ω (3) [ C cos( m d t) ]} S sin( m d t) where ( ω) is the dilution factor, ω is the difference in mistag probabilities ω ω B ω B and R is the resolution function. The parameters of the resolution function are obtained from a fit to a large sample of fully reconstructed B decays, as in [5], and are free to differ between tagging categories. The analyses of the two-body and quasi-two-body decays described in the remaining of this paper rely on a common strategy for the suppression of the continuum e + e q q background (q = u, d, s, c), which represents the most abundant source of background. Two kinematic variables, the energy substituted mass m ES = s/4 p B and the energy difference E = E B s/, where s is the e + e CM energy and the four-momentum (E B, p B ) of the B meson is defined in the CM frame, allow to discriminate correctly reconstructed B candidates (for which the distribution of m ES peaks at the B-meson mass and that of E peaks at zero) and fake candidates resulting from random combination of particles (for which m ES follows a phase-space distribution and E is approximately flat). Topological variables provide further distinction between the jet-like shape of continuum events and the more isotropic B decays, and can be combined into multivariate classifiers, such as neural network and Fisher discriminant, to enhance the discriminating power. The signal and background yields and CP asymmetries are extracted via an extended unbinned maximum-likelihood (ML) fit to the data. 3. Isospin analysis of B ππ decays 3.. B π + π In the ππ system the penguin pollution is greatest. The tree (T) and penguin (P) amplitudes each contribute, with different weak (φ) and strong (δ) phases, with comparable magnitude. Direct CP violation, which is given by A CP = sinφsin δ/( T/P + P/T + cos φ cos δ), can, therefore, be within observational reach. B π + π decays are analyzed with the full BaBar dataset of 467 ± 5 million BB pairs [6]. A simultaneous ML fit to the π + π, π + K, K + π, and K + K final states is performed. K π separation is obtained by particle-identification (PID) observables (the Cherenkov angle Θ C in the DIRC [7] and ionization-energy loss de/dx in the tracking devices [8]). Additional separation between the final states under study is achieved from E: since the B meson is reconstructed from two oppositely charged tracks that are both given the pion mass hypothesis, each charged K in the final state results in a E displacement of about 45 MeV. We extract 394 ± 54 signal events. From the time distribution of B π + π decays a non-zero mixing-induced
3 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 3 C ππ.5 BABAR Preliminary the B + π + π mode in a model-independent isospin analysis [9]. Under the isospin symmetry, B ππ amplitudes can be decomposed in isospin I = (A ) and I = (A ) amplitudes. By virtue of Bose statistics, I = contributions are forbidden. The following relations hold [9]: - -C.L. = (/ )A + = A A, (4) A = A + A, A + = 3A, (5) S ππ Figure : S ππ + and C ππ + in B π + π : the central values, errors, and confidence-level (CL) contours, calculated from the square root of the change in the value of ln L compared with its value at the minimum [6]. The systematic errors are included. The measured value is 6.7σ from the point of no CP violation (S ππ + = and C ππ + = ). CP violation asymmetry S ππ + =.68 ±. ±.3 is observed with significance 6.3σ [6], as shown in Fig.. A non-zero direct CP violation asymmetry C ππ + =.5 ±.8 ±. is also extracted with significance 3.σ [6]. 3.. B π π The B π π decay is formed from pairs of π γγ candidates, where one of the photons can eventually be reconstructed from two tracks coming from a photon conversion γ e + e inside the electromagnetic calorimeter. The yield and the flavor tag- and time-integrated CP asymmetry A CP = C ππ are obtained from a ML fit to the kinematic variables E and m ES and the output of a neural network NN computed from event-shape variables, as well as the output of the B- flavor tagging algorithm. The background model accounts for correlations between NN and m ES. We observe 47±9 signal events (corresponding to B(B π π ) = (.83 ±. ±.3) 6 ) and extracts Cππ =.43±.6±.5 [6]. Since no reliable vertex information is extracted, Sππ can not be determined Isospin analysis of B ππ decays The rates and CP asymmetries of B π + π and B π π decays are combined with the results for where A ij (A ij ) are the amplitudes of B (B) decays to the π i π j final state. This yields the complex triangle relations: A + = A + A, (6) A + = A A. (7) Tree amplitudes receive contributions from both A and A, while gluonic penguin diagrams are pure I = amplitudes and do not contribute to B + π + π amplitudes. Possible contributions from electroweak penguins (EWP), which do not obey SU() isospin symmetry, are assumed to be negligible and are therefore ignored. Under this assumption, A + = A (a sizeable contribution from EWPs would result in A + A and would be signalled by an evidence of direct CP violation in B + π + π decays). If A + and A are aligned with a suitable choice of phases, the relations (6) and (7) can be represented in the complex plane by two triangles (Fig. ), and the phase difference between A + and A + is α. A + ~ A A + + A, A ~ ~ A Figure : Triangles in the complex plane describing the isospin relations Eq.(6) and Eq.(7). Constraints on the CKM angle α and on the penguin contribution α are obtained from a confidence level (CL) scan over the parameters of interest, α and α. Assuming the isospin-triangle relations (6) and (7) and the expression (), a χ for the five amplitudes (A +, A +, A, A +, A ) is calculated from
4 4 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 Table I Summary of the input to the isospin analysis of the ππ system [6, ]. Mode B( 6 ) C π + π 5.5 ±.4 ±.3.5 ±.8 ±. π + π 5. ±.46 ±.9 (.3 ±.8 ±.) π π.83 ±. ±.3.43 ±.6 ±.5 the measurements summarized in Table I, and minimized with respect to the parameters that don t enter the scan. The CL values are then calculated from the probability of the minimized χ. The results of the isospin analysis are shown in Fig. 3 and Fig. 4. α is extracted with a four-fold ambiguity, which can be graphically represented as a flip of either triangle around A +. An additional two-fold ambiguity arises from the trigonometric relation S ππ + = sin(α eff ) C ππ +. This results in a global eight-fold ambiguity in the range [, 8] on the extraction of α. A value α < 43 at 9% CL is obtained, which dominates the uncertainty on α [6]. Considering only the solution consistent with the results of global CKM fits, α is in the range [7, 9] at the 68% CL [6]. The limiting factor in the extraction of α is the knowledge of A and A, which is severely limited by the available statistics. A significant increase in statistics is therefore required in order to perform a precision measurement of α in this channel. A measurement of Sππ, which would aid resolving some ambiguities on α, can only be addressed with Super B factory luminosities []. 4. Isospin analysis of B ρρ decays With respect to B ππ decays, B ρρ decays have a more favourable penguin to tree amplitude ratio. Moreover, the BF for B ρ + ρ decays is greater than that for B π + π decays by a factor of 5 []. Finally, the B ρ ρ decay can be reconstructed from a final state consisting of all charged tracks, with enough efficiency to allow for a measurement of Sρρ with the present statistics [3]. Despite these many advantages with respect to the isospin analysis of ππ decays, the ρρ system exhibits some potential complications. In B ρ + ρ transitions, a pseudo-scalar particle decays into two vector mesons. Three helicity states (H =, ±), with different CP transformation properties, can therefore contribute to the decay [4]. The H = state corresponds to longitudinal polarization and is CP-even, while the transverse polarization states H = + and H = (which are superpositions of S-, P-, and D-wave amplitudes) have not a definite CP-eigenvalue. Isospin relations similar to Eq. (6) and (7) hold separately for each polarization state. The analysis of the angular distribution of B ρ + ρ decays allows to determine the longitudinal polarization fraction f L : d Γ 4f L cos θ cos θ Γ d cosθ d cosθ +( f L )sin θ sin θ, (8) where θ (θ ) is the angle between the daughter π and the direction opposite to the B direction in the ρ + (ρ ) rest frame, as shown in Fig. 5. Since experimental measurements have shown the decay to be dominated by the longitudinal, CP-even polarization, it is not necessary to separate the definite-cp contributions of the transverse polarization by means of a full angular analysis. A second complication arises because the ρ mesons have finite width, thus allowing for the two ρ mesons - C.L BABAR Preliminary α - α eff (degrees) - C.L α (degrees) Figure 3: Projection of the CL scan on α for the ππ system [6]. Figure 4: Projection of the CL scan on α for the ππ system [6].
5 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 5 φ ρ π θ -CL π θ + ρ π +.5 π Figure 5: Definition of the θ and θ angles in B ρρ decays []. in the decay to have different masses. Since the Bose- Einstein symmetry does not hold, the wave function of the ρρ system can be anti-symmetric, and isospin I = amplitudes are allowed, breaking the isospin relations Eq.(6) and (7) [5]. The stability of the fitted CP-violation parameters against the restriction of the ππ invariant mass window used to select the ρ candidates shows however that possible isospin violation effects are below the current sensitivity. - =α-α (deg) α eff Figure 6: Projection of the CL scan on α for the ρρ system [6]. -CL 4.. B + ρ + ρ The B + ρ + ρ decay analysis has been updated using the final BaBar dataset of 44 fb [6], superseding the previous analysis based on fb [7]. An analysis of the angular distributions of B + ρ + ρ decays is performed. The signal yield and longitudinal polarization fraction is extracted via a ML fit to the kinematic quantities m ES, E, the output of a neural network N N based on event-shape variables, the mass of the ρ + and ρ candidates, and the cosines of the helicity angles θ ρ + and θ ρ, where θ ρ + (θ ρ ) is the angle between the daughter π (π ) and the direction opposite to the B direction in the ρ + (ρ ) rest frame. Improvements have been introduced on the charged particle reconstruction and on the background model, which takes into account correlations between N N, the cosine of the helicity angle, and the ππ invariant mass for each ρ meson in the final state. The measured BF increases from (8. ± 3.) 6 [7] up to (3.7 ±.4 ±.4) 6 [6]. The longitudinal polarization fraction is f L =.95 ±.5 ±.6 [6]. The measured direct CP-violation asymmetry A CP Γ(B ρ ρ ) Γ(B + ρ + ρ ) Γ(B ρ ρ )+Γ(B + ρ + ρ ) is A CP =.54 ±.55 ±., which is consistent with. This result indicates that the contribution from EWPs is negligible, and the isospin analysis holds within an uncertainty of [8]..5 CL=68% CL=9% 5 5 α (deg) Figure 7: Projection of the CL scan on α for the ρρ system [6]. The BFs, longitudinal polarization fractions, direct and mixing-induced CP violation asymmetries for B ρρ decays are used as input to the isospin analysis, and are summarized in Table II. The BF s of B + ρ + ρ and B ρ + ρ are now very similar and much higher than that for the B ρ ρ penguin transition. As a consequence, the isospin triangles do not close, i.e. A + / + A < A +. This results in a degeneracy of the eight-fold ambiguity on α into a four-fold ambiguity, corresponding to peaks in the vicinity of, 9 (two degenerate peaks), 8, as shown in Fig. 6 and Fig. 7. A value
6 6 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 Table II Summary of the input to the isospin analysis of the ρρ system [, 3, 6]. Mode B( 6 ) f L C S ρ + ρ 5.5 ± ± ±.5 ±.6.7 ± ρ + ρ 3.7 ±.4 ±.4.95 ±.4 ±.6 (.54 ±.55 ±.) - ρ ρ.9 ±.3 ± ±.4. ±.8 ±.3.3 ±.7 ±..8 < α < 6.7 at 68% CL is obtained. Considering only the solution consistent with the results of global CKM fits, α = The precision on α is now at the level of 5%. 5. B a (6) ± π It is possible to extract α from B decays to final states that are not CP-eigenstates [9], such as B a (6) ± π decays. The relevant amplitudes are: A + A(B a + π ), A + A( B a π+ ), (9) A A(B a π+ ), A A( B a + π ).() The time distribution for this decay mode is given by: dn a± π d t meas = ( ± A CP ) e t /τ 4τ q tag ( ω) R( t meas t), { q tag ω + [ (S ± S)sin( m d t) ]} (C ± C)cos( m d t) where A CP is the time- and flavor-integrated charge asymmetry, and S ± S Im ( ) e iβ A A ±, () A ± + A C ± C A ± A A ± + A. () The measured CP-violation parameters for B a (6) ± π decays are summarized in Table III []. Table III Values of the CP-violation parameters used as input to the calculation of the bounds on α []. A CP.7 ±.7 ±. S.37 ±. ±.7 S.4 ±. ±.6 C. ±.5 ±.9 C.6 ±.5 ±.7 In analogy to the π + π case, where α eff = arg [ e iβ A( B π + π )A (B π + π ) ], it is possible to define two quantities α + eff and α eff : α ± eff arg [ e iβ A ± A ±], (3) which are related by the phase ˆδ arg[a + A ] to the measurable quantities: α ± eff ± ˆδ = arg [ e iβ A ± A ] (4) S S = arcsin. (5) (C C) In the limit of zero penguin amplitudes, ˆδ coincides with the strong phase difference between the tree amplitudes contributing to B a (6) + π and B a (6) π + decays. An effective value α eff for the weak( phase α is then obtained as the average α eff = α + eff + eff) α with an eight-fold ambiguity []. It is possible to apply arguments based on the approximate SU(3) flavor symmetry to set bounds on α. The following ratios of CP-averaged rates of S = and S = transitions are calculated, that involve the same SU(3) flavor multiplet as a (6) [], such as B a (6) K +, B K + A π, B + a (6) + K, and B + KA π+ : R + λ f a B(B K + A π ) f K A B(B a + π ), (6) R + + λ f a B(B + K A π+ ) f K A B(B a + π ), (7) R λ f π B(B a K+ ) f K B(B a π+ ), (8) R + λ f π B(B+ a + K ) f K B(B a π+ ). (9) The bounds are effective because the penguin contribution is CKM enhanced by /λ = V cs / V cd in S = decays with respect to S = modes. The following inequalities involving (α ± eff α) hold: cos(α ± eff α) R ± A ± CP () cos(α ± eff α) R+ ±, () A ± CP
7 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 7 where A ± CP are the direct CP asymmetries A ± CP A ± A ± A ± + A ±. () The above relations set a constraint on (α ± eff α). Bounds on α are then derived from α ( α + eff α + α eff α )/. The BFs of B a (6)π and B a (6)K decays have been measured in the last few years []. The measurement of the missing piece of input, the BFs of B K (7)π and B K (4)π decays, is described in the following section. 5.. B K (7)π, B K (4)π The K A meson (the SU(3) partner of the a (6) meson) is a nearly equal superposition of the physical states K (7) and K (4). The rates of B K A π decays, which are experimental inputs to the calculation of the bounds on α, must be derived from the measurement of the rates of B K (7)π and B K (4)π decays. The BFs for these processes have recently been measured by BaBar []. The K (7) and K (4) axial vector mesons are broad resonances with nearly equal masses. In the following, we will refer to them collectively as K. The K (7) and K (4) mesons decay to the same final state Kππ, although through different intermediate states. However, since the intermediate decays proceed almost at threshold, the available phase spaces overlap and interference effects can be sizeable. The analysis strategy relies on the reconstructed Kππ invariant mass spectrum in the [.,.8] GeV range to distinguish between K (7) and K (4), including interference effects in the signal model. A two-resonance, six-channel K-matrix model is used to describe the resonant Kππ system for the signal [3]. The production amplitude for channel i = {(K π) S wave, (K π) D wave, ρk, Kπ, f K, ωk} is given by F i = e iδi ( ikρ) ij P j, (3) j where δ i are offset phases with respect to the (K π) S channel, K ij = f aif aj M a M + f bif bj M b M, (4) and P is the production vector P i = f paf ai M a M + f pbf bi M b M. (5) The labels a and b refer to K (4) and K (7), respectively, and the indexes i and j refer to the final states of K decays. The decay constants f ai, f bi, and the K-matrix poles M a and M b are real. The elements of the diagonal phase space matrix ρ(m) for the process K 3 + 4, have been approximated with the form ρ = δ ij m m 4 M m (M m + m m 4 + i ), (6) 4 where M is the mass of K, m 4 is the mass of 4, m is the mean mass of 3 and is the half width of 3. The parameters of K and the offset phases δ i are extracted from a fit to the data collected by the WA3 experiment [3] for the intensity of the Kππ channels and the relative phases. For the fit to WA3 data a background term is included in the production vector. The decay constants for the ωk channel are fixed according to the quark model [3]. The production constants f pa and f pb are expressed in terms of the production parameters ζ = (ϑ, φ): f pa cosϑ, f pb sinϑe iφ, where ϑ [, π/], φ [, π]. Signal Monte Carlo (MC) samples are generated by weighting the (Kππ)π population according to the amplitude i ωk Kππ i F i, where the term Kππ i consists of a factor describing the angular distribution of the Kππ system resulting from K decay, an amplitude for the resonant ππ and Kπ systems, and isospin factors. The BF of K ωk is accounted for as a correction to the total selection efficiency. The BF and the production parameters ϑ, φ for neutral and charged B meson decays to K (7)π + K (4)π are extracted via a ML fit to the kinematic observables m ES, E, a Fisher discriminant based on event-shape quantities, the Kππ invariant mass m Kππ and an angular variable. Background from B decays to K (4)π and non-resonant B decays to K ππ and ρkπ are taken into account as separate components in the fit. The dependence of the signal probability distribution in m Kππ and selection efficiencies on the production parameters ζ is described by means of non-parametric templates P(m Kππ ϑ, φ). Each event is classified according to the invariant masses of the π + π and K + π (K S π+ ) systems in the K + (K ) decay for B (B + ) candidates: events which satisfy the requirement.846 < m Kπ <.946 GeV belong to class ( K band ); events not included in class for which.5 < m ππ <.8 GeV belong to class ( ρ band ); all other events are rejected. For the B modes a likelihood scan is performed with respect to ϑ and φ. At each point, a simultaneous fit to the event classes r =, is performed. Although for events in the ρ band the signal to background ratio is worse than that for events in the K band, MC studies have shown that including those events in the fit helps in resolving the ambiguities in the determination of the parameter φ. For the B + modes, simulations show that, due to a less favourable signal to background ratio and increased background from
8 8 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 B decays, the analysis is not sensitive to φ. A value φ = π is therefore assumed and the scan is performed only with respect to ϑ. At each point of the scan, a fit to K band events only is performed. Figure 8 shows the distribution of E, m ES and m Kππ for the signal events obtained by the background-subtraction technique splot [4]. The experimental two-dimensional likelihood L for ϑ and φ is convolved with a two-dimensional Gaussian that accounts for the systematic uncertainties. The resulting distributions in ϑ and φ are shown in Fig. 9 (the 68% and 9% probability regions are shown in dark and light shading respectively, and are defined as the regions which satisfy L(r) > L min and L(r)>L min L(ϑ, φ)dϑdφ = 68% (9%)). A combined signal for B decays to K (7) + π and K (4) + π is observed with a significance of 7.5σ, while there s evidence for B + decays to K (7) π + and K (4) π + at 3.σ. The measured BFs are B(B K + π + K + π ) = and B(B + Kπ + + K π + ) = (< 8 6 at 9% probability), including systematic uncertainties []. The probability distributions for the B K (7)π, B K (4)π, and B K A π BFs are derived by setting the production parameters (f pa, f pb ) equal to (, e iφ sinϑ), (cosϑ, ), and ( f pa cosθ, f pa sin θ), respectively, where f pa = cosϑcosθ e iφ sin ϑ sinθ and θ is the K mixing angle. A value θ = 7 is used []. Including systematic uncertainties the following values are obtained (in units of 6 ): B(B K (7) + π ) = 7 +8, B(B K (4) + π ) = , B(B K + A π ) = 4 +9, B(B+ K (7) π + ) < 4, B(B + K (4) π + ) < 39, B(B + K A π+ ) < 36, where the upper limits are evaluated at 9% probability []. 5.. Extraction of α A MC technique is used to estimate a probability region for the bound on α. The CP-averaged rates and CP-violation parameters participating in the estimation of the bounds are generated according to the experimental distributions; a summary of the experimental values used as input to this calculation is provided in Table IV. For each set of generated values, the bound on α is evaluated. The limits on α are obtained by counting the fraction of bounds within a given value and the results are α <. (3. ) at 68% (9%) probability []. The angle α is extracted with an eight-fold ambiguity in the range [, 8]. The eight solutions are α = (±7±), α = (4±7±), α = (49±7±), α = (79 ± 7 ± ), α = ( ± 7 ± ), α = (3±7±), α = (39±7±), α = (69±7±). Table IV Summary of the B a (6)π and B a (6)K branching fractions (in units of 6 ) and of the form factors (in MeV) used in the calculation of α. B(a ± π ) [] B(a K + ) [] B(a + K ) [] 33. ± 3.8 ± ±.9 ± ± 5. ± 4.4 f π [4] f K [4] f a [5] f KA [6] 3.4 ± ±.9 3 ± 8 7 ± Assuming that the strong phase ˆδ is negligible [], only two solutions are still allowed. Considering only the solution consistent with the results of global CKM fits, α = (79 ± 7 ± ). 6. Conclusion Recent updates of measurements related to the determination of α have been presented. The first measurement of the branching fraction of B K π decays, combined with the input from the analysis of the time-dependent CP-violation asymmetries in B a (6) π ± decays and of the branching fractions of B a (6)K decays, allows to measure α in the a (6)π system. This novel determination of α is independent from, and consistent with, the current averages, which are based on the analysis of the ππ, ρπ, and ρρ systems only. With the new update of the B + ρ ρ + branching fraction and longitudinal polarization fraction measurements, the determination of α in the ρρ system has reached the unprecedented precision of 7%, comparable with the 5.3% precision achieved in sin β measurements. In the ππ system, the updated measurement of CPviolating asymmetries in B π + π decays provides a 6.7σ evidence of CP violation. B π π decays branching fraction and direct CP asymmetry are input to the isospin analysis of B ππ decays that is used to constrain the effect of penguin pollution on the extraction of α. All the measurements described in this work have been performed on the final BaBar sample. Most of them are still limited by statistics, and improvement may come from next generation, very high luminosity facilities. Acknowledgments I would like to thank the organizers of DPF 9 for an interesting conference and my BaBar and PEP-II collaborators for their contributions. I m grateful to Vincenzo Lombardo and Fernando Palombo for their support and for reviewing the manuscript.
9 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, (a) 5 (b) 6 4 (c) 5 5 Events 5 4 (d) (g) m ES (GeV) (e) -.. (h) -.. E (GeV) 3 (f) (i) m Kππ (GeV) Figure 8: splot projections of signal onto m ES (left), E (center), and m Kππ (right) for B class (top), B class (middle), and B + class (bottom) events: the points show the sums of the signal weights obtained from on-resonance data. For m ES and E the solid line is the signal fit function. For m Kππ the solid line is the sum of the fit functions of the decay modes K (7)π + K (4)π (dashed), K (4)π (dash-dotted), and K (89)ππ (dotted), and the points are obtained without using information about resonances in the fit, i.e., we use only the m ES, E, and F variables. φ (rad) 6 φ (rad) (a) (b).5 ϑ (rad).5.5 ϑ (rad).5 Figure 9: 68% (dark shaded zone) and 9% (light shaded zone) probability regions for ϑ and φ for the (a) B and (b) B + modes. References [] N. Cabibbo, Phys. Rev. Lett., 53 (963); M. Kobayashi and T. Maskawa, Prog. Theor. Phys. 49, 65 (973). [] M. Bona et al. (UTfit Collaboration), JHEP 63, 8 (6). [3] J. Charles et al. (CKMFitter Group), Eur. Phys. Jour. C 4, (5). [4] C. Amsler et al. (Particle Data Group), Phys. Lett. B 667, (8). [5] B. Aubert et al. (BABAR Collaboration), Phys. Rev. D 66, 33 (). [6] B. Aubert et al. (BABAR Collaboration), arxiv:87.46 [hep-ex] (8). [7] I. Adam et al. (BABAR-DIRC Collaboration), Nucl. Instr. Meth. A 538, 8 (5). [8] B. Aubert et al. (BABAR Collaboration),
10 Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 Nucl. Instr. Meth. A 479, (). [9] M. Gronau and D. London, Phys. Rev. Lett. 65, 338 (99). [] B. Aubert et al. (BABAR Collaboration), Phys. Rev. D 76, 9R (7). [] M. Bona et al., arxiv:79.45 [hep-ex] (7); S. Hashimoto et al., KEK-REPORT-4-4 (4). [] B. Aubert et al. (BABAR Collaboration), Phys. Rev. D 76, 57 (7). [3] B. Aubert et al. (BABAR Collaboration), Phys. Rev. D 78, 74R (8). [4] A. L. Kagan, Phys. Lett. B 6, 5 (4). [5] A. F. Falk, Z. Ligeti, Y. Nir, and H. Quinn, Phys. Rev. D 69, 5 (4). [6] B. Aubert et al. (BABAR Collaboration), Phys. Rev. Lett., 48 (9). [7] B. Aubert et al. (BABAR Collaboration), Phys. Rev. Lett. 97, 68 (6). [8] M. Gronau and J. Zupan, Phys. Rev. D 7, 747 (5). [9] R. Aleksan et al., Phys. Lett. B 356, 95 (995). [] B. Aubert et al. (BABAR Collaboration), Phys. Rev. Lett. 97, 58 (6); Phys. Rev. Lett. 98, 883 (7); Phys. Rev. Lett., 583 (8). [] M. Gronau and J. Zupan, Phys. Rev. D 73, 575 (6); Phys. Rev. D 7, 743 (4). [] B. Aubert et al. (BABAR Collaboration), arxiv:99.7 [hep-ex] (9). [3] C. Daum et al. (ACCMOR Collaboration), Nucl. Phys. B87, (98). [4] M. Pivk and F. R. Le Diberder, Nucl. Instr. Meth. A 555, 356 (5). [5] H.-Y. Cheng and K.-C. Yang, Phys. Rev. D 76, 4 (7). [6] J. C. R. Bloch, Yu. L. Kalinovsky, C. D. Roberts, and S. M. Schmidt, Phys. Rev. D 6, 5(R) (999).
Hiroyuki Sagawa KEK OHO 1-1, Tsukuba, Ibaraki, Japan
Hiroyuki Sagawa KEK OHO 1-1, Tsukuba, Ibaraki, Japan In the neutral B meson system, it is possible to measure the CKM angle α using the decay mode b uud in the presence of penguin pollution. Here the recent
More informationAdrian Bevan Department of Physics Liverpool University Liverpool, United Kingdom (from the BABAR Collaboration.)
BABAR-PROC-04/138 SLAC-PUB-10874 Measurements of sin 2α/φ 2 from B ππ, ρπ and ρρ modes. Adrian Bevan Department of Physics Liverpool University Liverpool, United Kingdom (from the BABAR Collaboration.)
More informationB Factories. Alan Watson University of Birmingham, UK
Towards (φ ) and γ (φ ) at the 2 3 B Factories Alan Watson University of Birmingham, UK The Unitarity Triangle Source of CP in the Standard Model 1 λ 2 /2 λ Aλ 3 (ρ iη) V CKM λ 1 λ 2 /2 Aλ 2 Αλ 3 (1 ρ
More informationCP violation in B 0 π + π decays in the BABAR experiment. Muriel Pivk, CERN. 22 March 2004, Lausanne
CP violation in B π + π decays in the BABAR experiment, 22 March 24, The BABAR experiment at SLAC 2 Phenomenology 3 The h + h analysis 4 A new tool: s Plots 5 Results 6 Interpretation of the results 7
More informationDecadimenti senza charm e misure di α alle B-Factory
Decadimenti senza charm e misure di α alle B-Factory Marcella Bona INFN e Università di Torino Incontri sulla Fisica delle Alte Energie Quark pesanti Lecce, 24 Aprile 2003 IFAE Lecce, Quark Pesanti, 24
More informationRecent BaBar results on CP Violation in B decays
Journal of Physics: Conference Series OPEN ACCESS Recent BaBar results on CP Violation in B decays To cite this article: Arantza Oyanguren 2013 J. Phys.: Conf. Ser. 447 012029 View the article online for
More informationarxiv: v3 [hep-ex] 11 Feb 2013
q/p Measurement from B 0 D lν Partial Reconstruction arxiv:1301.0417v3 [hep-ex] 11 Feb 2013 Martino Margoni on behalf of the BaBar Collaboration Università di Padova and INFN sezione di Padova Padova,
More informationDalitz Plot Analyses of B D + π π, B + π + π π + and D + s π+ π π + at BABAR
Proceedings of the DPF-9 Conference, Detroit, MI, July 7-3, 9 SLAC-PUB-98 Dalitz Plot Analyses of B D + π π, B + π + π π + and D + s π+ π π + at BABAR Liaoyuan Dong (On behalf of the BABAR Collaboration
More informationCP Violation in B Decays at Belle
Journal of Physics: Conference Series CP Violation in B Decays at Belle To cite this article: Masaya Iwabuchi J. Phys.: Conf. Ser. 335 37 View the article online for updates and enhancements. Related content
More informationnew measurements of sin(2) & cos(2) at BaBar
new measurements of sin(2) & cos(2) at BaBar, UC Irvine For the BaBar collaboration ICHEP24 August 16th, Beijing bruinsma@slac.stanford.edu Decay rates of B mesons 2 Time-dependent rates for B (f + ) or
More informationLatest time-dependent CP-violation results from BaBar
Latest time-dependent CP-violation results from BaBar Owen Long, UC Santa Barbara TM All results are preliminary XXXVIIth Rencontres de Moriond QCD and Hadronic Interactions March 17, 2002 The CKM matrix
More informationDepartment of Physics and Astronomy, University of California, Riverside, CA, USA
Recent results on charmless B meson decays from Babar Department of Physics and Astronomy, University of California, Riverside, CA, 92521 USA E-mail: bill.gary@ucr.edu Recent results from the Babar experiment
More informationMeasuring the Unitarity Triangle Angle α with BaBar. Adrian Bevan KEK, 15 th September 2006
(C) Peter Ginter (2002). Measuring the Unitarity Triangle Angle α with BaBar Adrian Bevan KEK, 15 th September 2006 (α, β, γ) (φ 1, φ 2, φ 3 ) 15 th September 2006 Adrian Bevan 1 Overview Motivation PEP-II
More informationA.Mordá. INFN - Padova. 7 th July on behalf of the Belle2 Collaboration. CP Violation sensitivity at the Belle II Experiment
A. Mordá CP Violation sensitivity at the Belle II Experiment 7 th July 7 / CP Violation sensitivity at the Belle II Experiment A.Mordá on behalf of the Belle Collaboration INFN - Padova 7 th July 7 Introduction
More informationLecture III. Measurement of sin 2 in B K 0 S. Measurement of sin 2 in B + -, B + - Measurement of in B DK. Direct CP Violation
Lecture III Measurement of sin 2 in BK S Measurement of sin 2 in BK S Measurement of sin 2 in B + -, B + - Measurement of in BDK Direct CP Violation Model-independent Test for New Physics Prospects Strategy
More informationPoS(Kruger 2010)048. B X s/d γ and B X s/d l + l. Martino Margoni SLAC-PUB Universita di Padova and INFN
SLAC-PUB-15491 B X s/d γ and B X s/d l + l Universita di Padova and INFN E-mail: martino.margoni@pd.infn.it Flavour Changing Neutral Current transitions B X s/d γ and B X s/d l + l provide an excellent
More informationMeasurement of ϕ 2 /α using
Measurement of ϕ 2 /α using Decays at elle and aar lexander Somov CKM 6, Nagoya 26 Introduction (CP violation in decays Measurements in φ 2 constraint from an Isospin analysis CP Violation in decays Tree
More informationCP Violation in B Decays and the CKM Matrix. Emmanuel Olaiya Rutherford Appleton Laboratory Chilton,Didcot,Oxon,OX11 0QX,UK
XXIV Physics in Collision - Boston, June 27-29, 24 CP Violation in B Decays and the CKM Matrix Emmanuel Olaiya Rutherford Appleton Laboratory Chilton,Didcot,Oxon,OX11 QX,UK ABSTRACT Results by the BaBar
More informationCracking the Unitarity Triangle
Cracking the Unitarity Triangle Latest Results from BABAR Masahiro Morii Harvard University NEPPSR 2004, Craigville, MA Unitarity Triangle Already seen it a few times this week VV + VV + VV = 0 ud ub cd
More informationMeasuring α with the B-factories. Adrian Bevan SCIPP 17 th Feb 04
Measuring α with the B-factories Adrian Bevan SCIPP 17 th Feb 4 Outline CP Violation in Meson Decay & measuring α Experiments and Techniques measurements in the B meson system: B ππ from Belle and BaBar
More informationRecent Results on Rare B Decays from BaBar and Belle
SLACPUB-97 April 3 1 Recent Results on Rare B Decays from BaBar and Belle B. Brau a, a Laboratory for Nuclear Science, Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge, MA, 2139
More informationMeasurement of time dependent CP violation in B φks. Mahalaxmi Krishnamurthy University of Tennessee. BaBar Collaboration Beauty 2003
Measurement of time dependent CP violation in B φks Mahalaxmi Krishnamurthy University of Tennessee BaBar Collaboration Beauty 2003 CMU, Pittsburgh 1 b-> sss Decays CP violation from interference of decay
More informationCharmless hadronic B decays at BABAR
BABAR-CONF-01/71 SLAC-PUB-9045 hep-ex/011017 October, 2001 Charmless hadronic B decays at BABAR Marcella Bona INFN and University of Torino Via Pietro Giuria 1, Torino E-mail: bona@to.infn.it (on behalf
More informationHow well do we know the Unitarity Triangle? An experimental review
SLAC-PUB-1281 hep-ex/78.3238 September 27 How well do we know the Unitarity Triangle? An experimental review Massachusetts Institute of Technology, Department of Physics, Room 26-443, 77 Massachusetts
More informationMeasuring α with B ρρ and ρπ
Measuring with B ρρ and ρπ Andrei Gritsan LBNL May 14, 2005 U. of WA, Seattle Workshop on Flavor Physics and QCD Outline Minimal introduction = arg[v td Vtb/V ud Vub] with b u and mixing penguin pollution
More informationMeasurement of CP Violation in B s J/ΨΦ Decay at CDF
Measurement of CP Violation in B s J/ΨΦ Decay at CDF Gavril Giurgiu Johns Hopkins University University of Virginia Seminar April 4, 2012 Introduction - CP violation means that the laws of nature are not
More informationRare Hadronic B decays at BaBar
Rare Hadronic B decays at BaBar Mirna van Hoek University of Colorado On behalf of the BaBar Collaboration 18 th International Workshop on Weak Interactions and Neutrinos January 21-26, 2002 Christchurch,
More informationLepton Universality Test in Υ(1S) decays at BABAR
Proceedings of the DPF-2009 Conference, Detroit, MI, July 27-31, 2009 SLAC-PUB-14946 Lepton Universality Test in Υ(1S) decays at BABAR Elisa GUIDO (on behalf of the BABAR Collaboration) Università degli
More informationD0 and D+ Hadronic Decays at CLEO
and + Hadronic ecays at CLEO K π π + + + Cornell University K π π + CLEO collaboration and branching fractions oubly Cabibbo suppressed branching fractions: K and K S vs. K L alitz analyses: K K and +
More informationPoS(CKM2016)087. Measurements of m d,s and Γ d at LHCb. Stefania Vecchi INFN, Sezione di Ferrara, Ferrara, Italy
INFN, Sezione di Ferrara, Ferrara, Italy E-mail: vecchi@fe.infn.it In this proceedings the latest measurements of the mixing properties of the neutral B mesons performed by the collaboration are presented.
More informationSearches for CP violation in decays from BABAR and Belle
D Searches for CP violation in decays from BABAR and Belle Maurizio Martinelli on behalf of the BABAR Collaboration Università degli Studi di Bari and INFN FPCP 1 May 7 1, Torino ITALY CP violation in
More informationPoS(CKM2016)100. Measurement of γ from time-dependent analysis of. Agnieszka Dziurda. CERN
Measurement o γ rom time-dependent analysis o B s D s K ± CERN E-mail: agnieszka.dziurda@cern.ch We report the measurement o the time-dependent CP violating observables in B s D s K ± decays. The study
More informationSTATUS OF CKM ANGLE MEASUREMENTS, A REPORT FROM BABAR AND BELLE
SLAC-R-950 STATUS OF CKM ANGLE MEASUREMENTS, A REPORT FROM BABAR AND BELLE Owen Long Department of Physics and Astronomy, University of California, Riverside CA 92521, USA I will review the latest developments
More informationPoS(CHARM2016)074. Searches for CPV in D + decays at LHCb
Università di Pisa and Sezione INFN di Pisa, Pisa, Italy E-mail: simone.stracka@cern.ch Singly-Cabibbo-suppressed D + decays are a good place to search for CP violation in charm, (s which in the Standard
More informationarxiv: v2 [hep-ex] 8 Aug 2013
-PROC-13-6 May 11, 1 Studies of charmless B decays including CP violation effects arxiv:138.7v [hep-ex] 8 Aug 13 Irina Nasteva 1 Centro Brasileiro de Pesquisas Físicas Rio de Janeiro, Brazil The latest
More informationCP Violation sensitivity at the Belle II Experiment
CP Violation sensitivity at the Belle II Experiment for the Belle II collaboration Max-Planck-Institut für Physik, München 29th Rencontres de Blois May 30th 2017 The Unitarity Triangle All flavor variables
More informationB Mixing and Lifetime Measurements with the BABAR Detector.
SLAC-PUB-8791 BABAR-PROC-1/8 hep-ex/1346 March 27th, 21 B Mixing and Lifetime Measurements with the BABAR Detector. Concezio Bozzi INFN Sezione di Ferrara Via Paradiso 12, I-441 Ferrara, Italy (representing
More informationNew Physics search in penguin B-decays
New Physics search in penguin B-decays Sanjay Swain, SLAC on behalf of BABAR Collaboration 13 th -18 th Dec 2007 Miami 2007 Outline What is New Physics (NP)? b > (d, s) penguin decays Exclusive Semi-inclusive
More informationStudies of CP Violation at BABAR
SLAC-PUB-878 BABAR-PROC-/32 hep-ex/1336 February, 21 Studies of CP Violation at BABAR Anders Ryd 1 California Institute of Technology, 356-48, Pasadena CA 91125 (for the BABAR Collaboration) Abstract BABAR
More informationarxiv: v1 [hep-ex] 14 Sep 2015
WSU HEP XXYY September 5, 5 arxiv:59.3v [hep-ex] Sep 5 Search for CP violation in D K + K, π + π and D π π Tara Nanut Department for Experimental Particle Physics Jozef Stefan Institute, Jamova 39, Ljubljana,
More informationResults on Searches for New Physics at B Factories
SLAC-PUB-14826 Results on Searches for New Physics at B Factories Gerald Eigen, representing the BABAR collaboration University of Bergen - Dept of Physics Allegaten 55, Bergen, Norway We summarize recent
More informationωω: J. Albert Caltech March 24, 2006
ωω: Search for B 0 ωφ and B 0 ωω Are CP and polarization in loops consistent Are CP and polarization in loops consistent with the Standard Model? with the Standard Model? March 24, 2006 J. Albert Caltech
More informationDiscovery searches for light new physics with BaBar
SLAC-PUB-1548 Discovery searches for light new physics with BaBar Neus Lopez-March BABAR Collaboration E-mail: neus.lopezmarch@epfl.ch The BABAR experiment collected large samples of events during the
More informationLHCb Physics and prospects. Stefano Perazzini On behalf of LHCb Collabora4on MENU nd June 2010
LHCb Physics and 2010-11 prospects Stefano Perazzini On behalf of LHCb Collabora4on MENU2010 2 nd June 2010 Physics: OUTLINE Flavor physics and CPV in the quark sector Search for New Physics The LHCb Experiment
More informationBABAR Status & Physics Reach in Coming Years
BABAR Status & Physics Reach in Coming Years Gautier Hamel de Monchenault CEA-Saclay DAPNIA/SPP on behalf of the BABAR Collaboration CERN, 14 February 2006 Status of PEP-2 and BABAR PEP-2 and BABAR at
More informationMeasurements of Leptonic B Decays from BaBar
Measurements of Leptonic B Decays from BaBar Gregory Dubois-Felsmann Caltech for the BaBar collaboration ICHEP 2004 Heavy Quark Mesons and Baryons session Overview Motivations for studying leptonic B decays
More informationIntroduction to Dalitz-plot
Introduction to Dalitz-plot Gagan Mohanty Student Seminar @ TIFR January 7, 01 Few Diversions Hierarchical expansion of CKM (1983) + O( 4) magnitudes d s b phases d s b u c t u c t 3 A triangle at the
More informationarxiv:hep-ph/ v4 18 Nov 1999
February 8, 018 arxiv:hep-ph/990998v4 18 Nov 1999 OITS-678 CLEO measurement of B π + π and determination of weak phase α 1 K. Agashe and N.G. Deshpande 3 Institute of Theoretical Science University of
More informationub + V cd V tb = 0, (1) cb + V td V
REVIEW OF β, α AND γ MEASUREMENTS K. TRABELSI KEK (High Energy Accelerator Research Organization) Institute of Particle and Nuclear Studies 1-1 Oho, Tsukuba-shi, Ibaraki-ken, 35-81, Japan Precision measurements
More informationRencontres de Moriond - EW Interactions and Unified Theories La Thuile, March 14-21, 2015
Rencontres de Moriond - EW Interactions and Unified Theories La Thuile, March 14-21, 2015 Eli Ben-Haïm LPNHE-IN2P3- Université Pierre et Marie Curie (Paris) On behalf of the BELLE and BABAR collaborations
More informationSin2β and Cos2β from b ccd and b cud transitions at BABAR
Sin2β and Cos2β from b ccd and b cud transitions at BABAR Alessandro Gaz University & INFN Padova on behalf of the BABAR Collaboration 4th International Workshop on the CKM Unitarity Triangle December
More informationStephen R. Armstrong CERN EP Division CH-1211 Geneva 23, SWITZERLAND
New Results on B 0 s Mixing from LEP Stephen R. Armstrong CERN EP Division CH-1211 Geneva 23, SWITZERLAND Contribution to Flavour Physics and CP Violation 16-18 May 2002 Philadelphia, Pennsylvania, USA
More informationStudy of e + e annihilation to hadrons at low energies at BABAR
Study of e + e annihilation to hadrons at low energies at BABAR V.Druzhinin Novosibirsk State University, BINP, Novosibirsk on behalf of the BABAR Collaboration International Symposium Advances in Dark
More informationObservation of Large CP Violation in the Neutral B Meson System
Observation of Large CP Violation in the Neutral B Meson System Presentation for PHY7357 final exam Yefan Tao Phys.Rev.Lett.87:091802,2001 Background: In 1973, Kobayashi and Maskawa(KM) proposed quark
More informationE (GeV) E (GeV) E (GeV) Entries/2.5 MeV/c
SLAC-PUB-8731 BABAR-PROC-/4 hep-ex/1237 December, 2 The BABAR Measurement of sin2 and its Future Prospects James Weatherall University of Manchester Department of Physics and Astronomy, University of Manchester,
More informationMEASUREMENT OF BRANCHING FRACTIONS OF B DECAYS TO K 1 (1270)π AND K 1 (1400)π AND DETERMINATION OF THE CKM ANGLE α FROM B 0 a 1 (1260) ± π
SLAC R 957 UNIVERSITÀ DEGLI STUDI DI MILANO SCUOLA DI DOTTORATO FISICA, ASTROFISICA E FISICA APPLICATA DIPARTIMENTO DI FISICA CORSO DI DOTTORATO DI RICERCA IN FISICA, ASTROFISICA E FISICA APPLICATA CICLO
More informationThis proceeding covers recent measurements of charmless hadronic B decays such as B +
Hanyang University E-mail: ymgoh@hep.hanyang.ac.kr ByungGu Cheon Hanyang University E-mail: bgcheon@hanyang.ac.kr Yuuji Unno Hanyang University E-mail: yunno@post.kek.jp This proceeding covers recent measurements
More informationResults on top physics by CMS
EPJ Web of Conferences 95, 04069 (2015) DOI: 10.1051/ epjconf/ 20159504069 C Owned by the authors, published by EDP Sciences, 2015 Results on top physics by CMS Silvano Tosi 1,2,a, on behalf of the CMS
More informationWeak Decays, CKM, Anders Ryd Cornell University
Weak Decays, CKM, CP Violation Anders Ryd Cornell University Presented at the International Conference on Weak Interactions and Neutrinos Delphi, Greece, June 6-11, 2005 Page: 1 Flavor Physics The study
More informationCKM phase and CP Violation in B Decays
CKM phase and CP Violation in B Decays David Brown Lawrence Berkeley National Lab BaBar Collaboration August 14, 2007 Daegu, Korea Talk Outline Review of CPV in the B system Results on the CKM unitarity
More informationRecent CP violation measurements. Advanced topics in Particle Physics: LHC physics, 2011 Jeroen van Tilburg 1/38
Recent CP violation measurements Advanced topics in Particle Physics: LHC physics, 2011 Jeroen van Tilburg 1/38 Recap of last week What we have learned last week: Indirect searches (CP violation and rare
More informationLa Fisica dei Sapori Pesanti
La Fisica dei Sapori Pesanti Lina Barbaro Galtieri Simposio in onore di Romano Bizzarri Roma, La Sapienza, 10 Febbraio 2004 Lina Galtieri Simposio in onore di Romano Bizzarri, Roma 10 Febbraio 2004 1 Heavy
More informationarxiv:hep-ph/ v1 22 Mar 1999
CLNS 99/605 Bounding the penguin effects in determinations of α from B 0 (t) π + π arxiv:hep-ph/9903447v 22 Mar 999 Dan Pirjol Floyd R. Newman Laboratory of Nuclear Studies, Cornell University, Ithaca,
More informationMeasurement of angle β with time-dependent CP asymmetry in. Emanuele Di Marco Università di Roma La Sapienza and INFN Roma December,
Measurement of angle β with time-dependent CP asymmetry in B 0 K + K - K 0 decays Emanuele Di Marco Università di Roma La Sapienza and INFN Roma December, 14 2006 b d CP violation in B 0 φk 0 and K + K
More informationCP Violation: Recent Results from BABAR
CP Violation: Recent Results from BABAR Gautier Hamel de Monchenault To cite this version: Gautier Hamel de Monchenault. CP Violation: Recent Results from BABAR. LAC-PUB-9816. 8 pages - talk given on behalf
More informationSUSY-related Lepton and Hadron Flavor Results from Belle Yutaro Sato
SUSY-related Lepton and Hadron Flavor Results from Belle Yutaro Sato For the Belle Collaboration (Nagoya Univ., KMI) 27 th Aug. 2015, SUSY2015 @ Lake Tahoe, USA New physics search at Belle 2 New particles
More informationCP Violation in the B(s) meson system at LHCb Julian Wishahi on behalf of the LHCb collaboration
CP Violation in the B(s) meson system at Julian Wishahi on behalf of the collaboration 5th Rencontres de Moriond, Electroweak Session, 2th of March 215 CPV in Interference of Mixing/Decay interference
More informationD 0 -mixing and CP Violation in Charm at Belle
D 0 -mixing and CP Violation in Charm at Belle Marko Starič Belle collaboration Jožef Stefan Institute, Ljubljana Xth Rencontres du Vietnam M. Starič (IJS) D 0 -mixing and CPV in Charm at Belle Quy Nhon,
More informationElectroweak Theory: 5
Electroweak Theory: 5 Introduction QED The Fermi theory The standard model Precision tests CP violation; K and B systems Higgs physics Prospectus STIAS (January, 2011) Paul Langacker (IAS) 162 References
More informationRecent results on CKM/CPV from Belle
Recent results on CKM/CPV from Belle Alexander Leopold for the Belle Collaboration Insitute of High Energy Physics Austrian Academy of Sciences HEPMAD 15, September 21 st 2015 A. Leopold (HEPHY) Belle
More informationSearches for Leptonic Decays of the B-meson at BaBar
Searches for Leptonic Decays of the B-meson at BaBar Stephen Jacob Sekula (MIT) on behalf of the BaBar collaboration Presented at Frontiers in Contemporary Physics III Vanderbilt University May 22-28,
More informationMeasurements of CP violating phases in B decays at LHCb
Measurements of CP violating phases in B decays at Sevda Esen [Heidelberg University] on behalf of the collaboration Les Rencontres de Physique de la Vallée d Aoste, 1-7 March 215 CP Violation in the SM
More informationThe other window on New Physics: CP violation at the B factories
The other window on New Physics: CP violation at the B factories Gabriella Sciolla M.I.T. Outline: The physics of CP violation What is CP and why is it interesting? CPV in the B system CPV in the Standard
More informationPoS(EPS-HEP2017)662. Charm physics prospects at Belle II
Dipartimento di Matematica e Fisica, Università di Roma Tre and INFN Sezione di Roma Tre, Via della vasca navale 84, I-00146 Rome, Italy E-mail: giacomo.depietro@roma3.infn.it Belle II is a major upgrade
More informationMeasurement of t-channel single top quark production in pp collisions
Measurement of t-channel single top quark production in pp collisions (on behalf of the CMS collaboration) INFN-Napoli & Università della Basilicata E-mail: Francesco.Fabozzi@cern.ch Measurements of t-channel
More informationMeasurement of Фs, ΔΓs and Lifetime in Bs J/ψ Φ at ATLAS and CMS
Measurement of Фs, ΔΓs and Lifetime in Bs J/ψ Φ at ATLAS and CMS Claudio Heller Excellence Cluster Universe LMU München For the ATLAS and CMS Collaborations Beauty 2013 14th International Conference on
More informationPoS(FPCP 2010)017. Baryonic B Decays. Jing-Ge Shiu SLAC-PUB National Taiwan University, Taiwan
SLAC-PUB-15541 Baryonic B Decays National Taiwan University, Taiwan E-mail: physjg@hep1.phys.ntu.edu.tw We present a summary of the recent studies on the baryonic B decays performed by the BaBar and Belle
More informationFleischer Mannel analysis for direct CP asymmetry. Abstract
Fleischer Mannel analysis for direct CP asymmetry SLAC-PUB-8814 hep-ph/yymmnnn Heath B. O Connell Stanford Linear Accelerator Center, Stanford University, Stanford CA 94309, USA hoc@slac.stanford.edu (8
More informationCKM Matrix and CP Violation in Standard Model
CKM Matrix and CP Violation in Standard Model CP&Viola,on&in&Standard&Model&& Lecture&15& Shahram&Rahatlou& Fisica&delle&Par,celle&Elementari,&Anno&Accademico&2014815& http://www.roma1.infn.it/people/rahatlou/particelle/
More informationPoS(CKM2016)113. Measurement of γ from B meson decay to D ( ) K ( )
LAL, Université Paris-Sud, CNRS/IN2P3, Orsay, France. E-mail: frederic.machefert@in2p3.fr The LHCb experiment has measured the angle γ of the unitarity triangle using B D ( ) K ( ) decays and with an integrated
More informationarxiv: v2 [hep-ex] 16 Oct 2015
Study of B Kππ Decays arxiv:151.4446v [hep-ex] 16 Oct 15 representing the collaboration Dept. of Physics, University of Bergen, Bergen, Norway E-mail: gerald.eigen@ift.uib.no Using 471 1 6 B B decays recorded
More informationNicolas Berger SLAC, Menlo Park, California, U.S.A.
SLAC-PUB-11414 August 25 Frascati Physics Series Vol. VVVVVV (xxxx), pp. - DAΦNE 24: Physics at meson factories Frascati, June. 7-11, 24 Selected Contribution in Plenary Session INCLUSIVE HADRONIC RESULTS
More informationLHCb Semileptonic Asymmetry
CERN E-mail: mika.vesterinen@cern.ch A recent measurement of the CP violating flavour specific asymmetry in B s decays, a s sl, is presented. This measurement is based on a data sample corresponding to
More informationarxiv: v1 [hep-ex] 14 Oct 2011
Proceedings of the DPF-211 Conference, Providence, RI, August 8-13, 211 1 Studies of b-hadron decays to charming final states at S. Ricciardi (on behalf of the Collaboration) STFC Rutherford Appleton Laboratory,
More informationPoS(ICHEP2012)238. Search for B 0 s µ + µ and other exclusive B decays with the ATLAS detector. Paolo Iengo
Search for B s µ + µ and other exclusive B decays with the ATLAS detector. On behalf of the ATLAS Collaboration INFN Naples, Italy E-mail: paolo.iengo@cern.ch The ATLAS experiment, collecting data in pp
More informationThe Cabibbo-Kobayashi-Maskawa (CKM) matrix
The Cabibbo-Kobayashi-Maskawa (CKM) matrix Charge-raising current J µ W = ( ν e ν µ ν τ )γ µ (1 γ 5 ) V = A u L Ad L e µ τ + (ū c t)γ µ (1 γ 5 )V Mismatch between weak and quark masses, and between A u,d
More informationStudies of charmonium production in e + e - annihilation and B decays at BaBar
Studies of charmonium production in e + e - annihilation and B decays at BaBar I. Garzia, INFN Sezione di Ferrara On behalf of the BaBar Collaboration XVI International Conference on Hadron Spectroscopy
More informationA. J. Schwartz Physics Department, University of Cincinnati, Cincinnati, Ohio USA
Physics Department, University of Cincinnati, Cincinnati, Ohio 51 USA E-mail: alan.j.schwartz@uc.edu (on behalf of the Belle II Collaboration) The Belle II experiment is under construction at the KEK laboratory
More informationRESULTS FROM B-FACTORIES
XL International Meeting on Fundamental Physics Benasque, May 12 RESULTS FROM B-FACTORIES (IFIC Valencia) τ - τ + τ - τ + B factories KEKB s=10.58 GeV e + e- Υ(4s) Υ(4s) B B z ~ c βγ τ B ~ 200µm BaBar
More informationDetermination of the phase φ s at LHCb
Determination of the phase φ s at LHCb Varvara Batozskaya 1,, on behalf of the LHCb Collaboration 1 National Centre for Nuclear Research (NCBJ), Warsaw, Poland Abstract. The determination of the mixing-induced
More informationA. Oyanguren (IFIC U. Valencia/CSIC)
A. Oyanguren (IFIC U. Valencia/CSIC) Outline Radiative b decays B s φγ B 0 K *0 e + e - [PRL 118(2017)021801] [JHEP04(2015)064] b-baryons: Λ b Λγ, Ξ b Ξ γ, Ω b Ωγ Conclusions A. Oyanguren 2 The LHCb experiment
More informationSearches for New Physics in quarkonium decays at BaBar/Belle
1 Searches for New Physics in quarkonium decays at BaBar/Belle Lucas Winstrom University of California Santa Cruz for the BaBar Collaboration Presented at QWG08 in Nara, Japan December 5, 2008 2 Outline
More informationRelative branching ratio measurements of charmless B ± decays to three hadrons
LHCb-CONF-011-059 November 10, 011 Relative branching ratio measurements of charmless B ± decays to three hadrons The LHCb Collaboration 1 LHCb-CONF-011-059 10/11/011 Abstract With an integrated luminosity
More informationSTUDY OF D AND D PRODUCTION IN B AND C JETS, WITH THE DELPHI DETECTOR C. BOURDARIOS
STUDY OF D AND D PRODUCTION IN B AND C JETS, WITH THE DETECTOR C. BOURDARIOS Université de Paris Sud, Laboratoire de l Accélérateur Linéaire, Bât. 2, B.P. 34, FR-91898 ORSAY CEDEX E-mail: claire.bourdarios@cern.ch
More informationarxiv: v1 [hep-ex] 23 Jul 2013
Semileptonic Mixing Asymmetry Measurements of A d SL and A s SL arxiv:1307.6114v1 [hep-ex] 23 Jul 2013 Martino Margoni 1 Università di Padova and INFN sezione di Padova Padova, ITALY Standard Model predictions
More informationIdentification of the Higgs boson produced in association with top quark pairs in proton-proton
Identification of the Higgs boson produced in association with top quark pairs in proton-proton collision: an analysis of the final state containing three leptons with the ATLAS detector Valentina Vecchio,
More informationOverview of LHCb Experiment
Overview of Physics @ LHCb Experiment Yuanning Gao, Tsinghua University Representing the LHCb Collaboration Detector performance CKM triangles Other topics (selected) Conclusions A very selective review!
More informationMeasurements of the phase φ s at LHCb
Measurements of the phase φ s at LHCb V. Batozskaya 1 on behalf of LHCb collaboration 1 National Centre for Nuclear Research, Warsaw, Poland XXIII Cracow Epiphany Conference 9-12 January 2017 V. Batozskaya
More informationMoriond QCD La Thuile, March 14 21, Flavour physics in the LHC era. An introduction. Clara Matteuzzi. INFN and Universita Milano-Bicocca
Moriond QCD La Thuile, March 14 21, 2009 Flavour physics in the LHC era An introduction Clara Matteuzzi INFN and Universita Milano-Bicocca 1 Contents 1. The flavor structure of the Standard Model 2. Tests
More informationTime-dependent CP violation
Time-dependent CP violation experimental results and prospects Paul Seyfert on behalf of the collaboration INFN Milano Bicocca 13th October 216 Paul Seyfert (INFN MIB) time dependent CPV implications workshop
More information