Using a sample of 68 million KL -> 3pi0 decays collected in 1996-1999 by the KTeV (E832) experiment at Fermilab, we present a detailed study of the KL -> 3pi0 Dalitz plot density. We report the first observation of interference from KL->pi+pi-pi0 decays in which pi+pi- rescatters to 2pi0 in a final-state interaction. This rescattering effect is described by the Cabibbo-Isidori model, and it depends on the difference in pion scattering lengths between the isospin I=0 and I=2 states, a0-a2. Using the Cabibbo-Isidori model, we present the first measurement of the KL-> 3pi0 quadratic slope parameter that accounts for the rescattering effect.
We report on the Dalitz plot analyses of B^- \to D^+ π^-π^-, B^+ \to π^+ π^- π^+ and D^+_s \to π^+ π^- π^+. The Dalitz plot method and the most recent BABAR results are discussed.
We describe Dalitz plots arising in studies of $D$-meson decays, and what we have learned from them in recent years. After some mention of technique and history, we focus on decay of the $D^\pm$ and $D_s^\pm$ mesons to the $K^-K^+π^\pm$ final state, and on $D_s^\pm$ decay to $π^+π^-π^\pm$. Some mention of other Dalitz plots involving $D$-meson decays is also made.
We present preliminary results on the measurement of the I=1/2 $K π$ $\mathcal{S}$-wave through a model independent partial wave analysis of $η_c$ decays to $K^0_S K^+ π^-$ and $K^+ K^- π^0$ produced in two-photon interactions. We also perform a Dalitz plot analysis of the $J/ψ$ decays to $π^+ π^- π^0$ and $K^+ K^- π^0$ produced by the initial state radiation process.
Dalitz Plot Analysis of D0 Hadronic Decays D0 -> K0K-pi+, D0 -> K0barK+pi- and D0 -> K0barK+K-
本文给出了D 0强子衰变D 0-> K 0 K-pi+，D 0-> K 0 bar K+ pi-和D 0-> K 0 bar K+ K-的Dalitz图分析。该分析基于在SLAC的PEP-II非对称能量B工厂运行的BABAR探测器在Y（4S）共振上或附近收集的22 fb-1的数据样本。这些事件是从使用衰变D*+ -> D 0 π +的连续e+ e-湮灭中选择的。初步测量了上述强子衰变的分支分数。初步估计的分数和相位的共振和非共振贡献的Dalitz图。
本文给出了强子衰变D_0-> K_0 bar K + K_-中重建的约12500个D_0事例的Dalitz图分析。该分析是基于91.5 fb-1的数据样本收集与BaBar探测器在PEP-II非对称能量e + e-存储环在SLAC运行在质心能量和40 MeV以下的Y4S共振。这些事件是从使用衰变D *+--> D0 π +的e + e-> c cbar湮灭中选择的。BR = γ（D_0-> K_0 bar K + K_-）/γ（D_0-> K_0 bar pi + pi_-）=（15.8 +/-0.1（stat.）+/- 0.5（系统）x 10 - 2还提供了对Dalitz图的共振和非共振贡献的分数和相位的估计。a0（980）--> K Kbar投影已在几乎没有背景的情况下被提取。搜索CP的Dalitz图上的不对称性已被执行。
We present a preliminary measurement of CP-violation parameters in the decay B0->K+K-Ks, using approximately 465 million BBbar events collected by the BABAR detector at SLAC. Reconstructing the neutral kaon as Ks->pi+pi- or Ks->pi0pi0, we analyze the Dalitz plot distribution and measure fractions to intermediate states. We extract CP parameters from the asymmetries in amplitudes and phases between B0 and B0bar decays across the Dalitz plot. From a fit to the whole Dalitz plot, we measure beta_eff = 0.44 +/- 0.07 +/- 0.02, A_CP = 0.03 +/- 0.07 +/- 0.02, where the first uncertainties are statist…
Dalitz plot analysis of e+ e- --> pi0 pi0 gamma events at SQRT(s) ~ M(phi) with the KLOE detector
本文研究了用KLOE探测器在SQRT（s）~ M（phi）上采集的e+ e-> pi 0 pi 0 γ事例的Dalitz图。在双介子不变质量（Mpp）低于700 MeV的区域中，所研究的过程由非共振过程e+ e-> omega -> pi 0和omega --> pi 0 γ主导，而对于更高的Mpp值，辐射phi衰变到f0（980）是主导机制。使用不同的理论模型来拟合Dalitz图，同时考虑到sigma（600）的可能贡献。对于每个模型，我们提取f0（980）质量及其与pipi，KKbar和phi的耦合。
We perform a Dalitz plot analysis of about 100,000 Ds+ decays to K+ K- pi+ and measure the complex amplitudes of the intermediate resonances which contribute to this decay mode. We also measure the relative branching fractions of Ds+ --> K+ K+ pi- and Ds+ --> K+ K+ K-. For this analysis we use a 384 fb-1 data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e+e- collider running at center-of-mass energies near 10.58 GeV.
We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi+/- pi-/+. Using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, we measure CP-averaged branching fractions and direct CP asymmetries for intermediate resonant and nonresonant contributions. We find evidence for direct CP violation in the decay B+ -> rho0(770) K+, with a CP violation parameter A_CP = (+44 +/- 10 +/- 4 +5,-13)%.
We report on a search for CP asymmetry in the singly Cabibbo-suppressed decay D+ -> K+ K- pi+ using a data sample of 818 pb-1 accumulated with the CLEO-c detector on the psi(3770) resonance. A Dalitz-plot analysis is used to determine the amplitudes of the intermediate states. We find no evidence for CP violation either in specific two-body amplitudes or integrated over the entire phase space. The CP asymmetry in the latter case is measured to be (-0.03+-0.84+-0.29)%.
We report preliminary results from a study of the decay B0 --> D0bar pi+ pi- using a data sample of 470.9 +/- 2.8 million BBbar events collected with the BaBar detector at the Y(4S) resonance. Using the Dalitz-plot analysis technique, we find contributions from the intermediate resonances D*_2(2460)-, D*_0(2400)-, rho(770)0 and f_2(1270) as well as a pi+ pi- S-wave term, a D0bar pi- nonresonant S-wave term and a virtual D*(2010)- amplitude. We measure the branching fractions of the contributing decays.
We perform an analysis of the $D^+\rightarrow K^0_S π^+ π^0$ Dalitz plot using a data set of 2.92 fb$^{-1}$ of $e^+e^-$ collisions at the $ψ(3770)$ accumulated by the BESIII Experiment, in which 166694 candidate events are selected with a background of 15.1%. The Dalitz plot is found to be well-represented by a combination of six quasi-two-body decay channels ($K^0_Sρ^+$, $K^0_Sρ(1450)^+$, $\overline{K}^{*0}π^+$, $\overline{K}_0(1430)^0π^+$, $\overline{K}(1680)^0π^+$, $\overlineκ^0π^+$) plus a small non-resonant component. We also consider a model-independent approach to confirm an obvious pha…
A Dalitz plot analysis of approximately 13,000 Ds+ decays to pi+pi-pi+ has been performed. The analysis uses a 384 fb-1 data sample recorded by the BaBar detector at the PEP-II asymmetric-energy e+e- storage ring running at center of mass energies near 10.6 GeV. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio of branching fractions is performed: BR(Ds+ -> pi+pi-pi+)/BR(Ds+ -> K+ K- pi+)=0.199 +/- 0.004 +/- 0.009. Using a model-independent partial wave analysis, the amplitude and phase of the S-wav…
We perform a Dalitz plot analysis of the decay Ds to K+K-pi+ with the CLEO-c data set of 586/pb of e+e- collisions accumulated at sqrt(s) = 4.17 GeV. This corresponds to about 0.57 million D_s+D_s(*)- pairs from which we select 14400 candidates with a background of roughly 15%. In contrast to previous measurements we find good agreement with our data only by including an additional f_0(1370)pi+ contribution. We measure the magnitude, phase, and fit fraction of K*(892) K+, phi(1020)pi+, K0*(1430)K+, f_0(980)pi+, f_0(1710)pi+, and f_0(1370)pi+ contributions and limit the possible contributions o…
We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa {\it CP}-violating phase $γ$ through a Dalitz plot analysis of neutral $D$ meson decays to $K_S^0 π^+ π^-$ and $K_S^0 K^+ K^-$ in the processes $B^\mp \to D K^\mp$, $B^\mp \to D^* K^\mp$ with $D^* \to Dπ^0,Dγ$, and $B^\mp \to D K^{*\mp}$ with $K^{*\mp} \to K_S^0 π^\mp$. Using a sample of 383 million $B\bar{B}$ pairs collected by the BABAR detector, we measure $γ=(76 \pm 22 \pm 5 \pm 5)^\circ$ (mod $180^\circ$), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects …
The decay $η\rightarrow π^+ π^- π^0$ is studied with the KLOE detector, at the DA$ϕ$NE e$^+$e$^-$ collider. Using a data sample corresponding to an integrated luminosity of $1.6$ fb$^{-1}$ a new study of the Dalitz plot is presented.
We present Dalitz plot analyses for the decays of $B$ mesons to $D^-D^0K^+$ and $\overline{D}^0D^0K^+$. [Charge conjugate reactions are implicitly assumed throughout.] We report the observation of the $D^*_{s1}(2700)^+$ resonance in these two channels and obtain measurements of the mass $M(D^*_{s1}(2700)^+) = 2699^{+14}_{-7}$ MeV/$c^2$ and of the width $Γ(D^*_{s1}(2700)^+) = 127^{+24}_{-19}$ MeV, including statistical and systematic uncertainties. In addition, we observe an enhancement in the $D^0K^+$ invariant mass around 2350--2500 MeV/$c^2$ in both decays $B^0 \to D^-D^0K^+$ and $B^+ \to \o…
Bose symmetry and $CPT$ symmetry are two very fundamental symmetries of Nature. However, the validity of these symmetries in diverse phenomena must be verified by experiments. We propose new techniques to probe these two fundamental symmetries in the realm of mesons by using the Dalitz plot of a few three-body meson decays. Since these symmetries are very fundamental in nature, their violations, if any, are expected to be extremely small. Hence observing their violations requires study of a huge data sample. In this context we introduce a new three-dimensional plot which we refer to as the Dal…
The Laura++ software package is designed for performing fits of amplitude models to data from decays of spin-0 particles into final states containing three spin-0 particles - so-called Dalitz-plot analysis. An overview of the amplitude formalism and its software implementation is given as well as summaries of recently added features and planned future developments.
We present a time-dependent Dalitz plot measurement of CP violation parameters in B0 --> Ks Pi+ Pi- decays. These results are obtained from a large data sample that contains 657 million BBbar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. For the CP violation parameters, we obtain two consistent solutions that describe the data well. The first of these solutions may be preferred by external information from other measurements. There is no evidence for direct CP violation in B0 --> rho0(770) Ks, B0 --> f0(980) Ks and B0 --> K*+(892) P…
We present an updated measurement of the unitarity triangle angle phi_3 using a Dalitz plot analysis of the K^0_S pi+ pi- decay of the neutral D meson produced in B+- ->D(*)K+- decays. The method exploits the interference between D^0 and Dbar^0 to extract the angle phi_3, strong phase delta and the ratio r of suppressed and allowed amplitudes. We apply this method to a 605 fb-1 data sample collected by the Belle experiment. The analysis uses two modes: B+- -> DK+-, and B+- -> D*K+- with D* -> D pi0, as well as the corresponding charge-conjugate modes. From a combined maximum likelihood fit to …
We report on a Dalitz plot analysis of B- -> D+ pi- pi- decays, based on a sample of about 383 million Upsilon(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. We find the total branching fraction of the three-body decay: BR(B- -> D+ pi- pi-) = (1.08 +/- 0.03 +/- 0.05) x 10^-3. The masses and widths of D^{*0}_2 and D^{*0}_0, the 2+ and 0+ cubar P-wave states decaying to D+ pi-, are measured: mass_{D^{*0}_2} = (2460.4 +/- 1.2 +/- 1.2 +/- 1.9) MeV/c2, width_{D^{*0}_2} = (41.8 +/- 2.5 +/- 2.1 +/- 2.0) MeV, mass_{D^{*0}_0} = (2297 +/- 8 +/- 5…
We present the first measurement of the angle phi_3 of the unitarity triangle using a binned model-independent Dalitz plot analysis technique of B->DK, D->Ks pi+pi- decay chain. The method is based on the measurement of parameters related to the strong phase of D->Ks pi+ pi- amplitude performed by the CLEO collaboration. The analysis uses full data set of 772x10^6 BBbar pairs collected by the Belle experiment at Upsilon(4S) resonance. We obtain phi3 = (77.3^{+15.1}_{-14.9} +- 4.2 +- 4.3) degree and the suppressed amplitude ratio rB = 0.145 +- 0.030 +- 0.011 +- 0.011. Here the first error is st…
We present Dalitz plot analyses for the decays of $B$ mesons to $D^- D^0 K^+$ and $\overline{D}^0 D^0 K^+$. We report the observation of the $D^{*}_{s1}(2700)^+$ resonance in these two channels and obtain measurements of the mass $M(D^{*}_{s1}(2700)^+) = 2699 {}^{+14}_{-7} \, \mathrm{MeV}/c^2$ and of the width $Γ(D^{*}_{s1}(2700)^+) = 127 {}^{+24}_{-19} \, \mathrm{MeV}$, including statistical and systematic uncertainties. In addition, we observe an enhancement in the $D^0K^+$ invariant mass around 2350--2500 MeV/$c^2$ in both decays $B^0 \to D^- D^0 K^+$ and $B^+ \to \overline{D}^0 D^0 K^+$, w…
We study the Dalitz plot of the Cabibbo-favored charmed-meson decay $D^+\to K^-π^+π^+$ using dispersion theory. The formalism respects all constraints from analyticity and unitarity, and consistently describes final-state interactions between all three decay products. We employ pion-pion and pion-kaon phase shifts as input, and fit the pertinent subtraction constants to Dalitz plot data by the CLEO and FOCUS collaborations. Phase motions of resonant as well as nonresonant amplitudes are discussed, which should provide crucial input for future studies of CP violation in similar three-body charm…
