Two-body hadronic charmed meson decays

Abstract

We study in this work the two-body hadronic charmed meson decays, including both the PP and VP modes. The latest experimental data are first analyzed in the diagrammatic approach. The magnitudes and strong phases of the flavor amplitudes are extracted from the Cabibbo-favored (CF) decay modes using $\chi^2$ minimization. The best-fitted values are then used to predict the branching fractions of the singly-Cabibbo-suppressed (SCS) and doubly-Cabibbo-suppressed decay modes in the flavor SU(3) symmetry limit. We observe significant SU(3) breaking effects in some of SCS channels. In the case of VP modes, we point out that the $A_P$ and $A_V$ amplitudes cannot be completely determined based on currently available data. We conjecture that the quoted experimental results for both $D_s^+\to\bar K^0K^{*+}$ and $D_s^+\to \rho^+\eta'$ are overestimated. We compare the sizes of color-allowed and color-suppressed tree amplitudes extracted from the diagrammatical approach with the effective parameters $a_1$ and $a_2$ defined in the factorization approach. The ratio $|a_2/a_1|$ is more or less universal among the $D \to {\bar K} \pi$, ${\bar K}^* \pi$ and ${\bar K} \rho$ modes. This feature allows us to discriminate between different solutions of topological amplitudes. For the long-standing puzzle about the ratio $\Gamma(D^0\to K^+K^-)/\Gamma(D^0\to\pi^+\pi^-)$, we argue that, in addition to the SU(3) breaking effect in the spectator amplitudes, the long-distance resonant contribution through the nearby resonance $f_0(1710)$ can naturally explain why $D^0$ decays more copiously to $K^+ K^-$ than $\pi^+ \pi^-$ through the $W$-exchange topology.Comment: 32 pages, 5 figures. An alternative method for error bar extraction is used; last columns of Tables~I to VI, and all entries in Tables~VII, VIII and X are modified. To appear in PRD

Dalitz plot studies ofD0→KS0π+

“…[18]. Reference [21], invoking a large N C approach, quotes the following a 1 ≃ C 1 (m c ) = 1.274 and a 2 ≃ C 2 (m c ) = −0.529 with m c (m c ) = 1.25 GeV, values extracted from Tables VI and VII of Ref. [32].…”

“…An alternative diagrammatic approach for the description of hadronic charmed meson decays into two body has been the support of the works presented in Refs. [21] and [22].…”

The UTfit collaboration average of D meson mixing data: spring 2012

“…Early combinations of available data allowed to put stringent constraints on New Physics (NP) contributions, although the possibility of non-standard CP violation remained open [4][5][6][7][8]. More recently, CP violation in the D system received considerable attention after the measurement at hadron colliders of large direct CP violation in D → ππ and D → KK decays [9,10], which may signal the presence of NP [11][12][13][14][15][16]. It then becomes crucial to extract updated information on the mixing amplitude in order both to disentangle more precisely indirect and direct CP violation in D → ππ and D → KK, and to obtain up-to-date constraints on NP in ∆C = 2 transitions that can be used to constrain NP contributions to ∆C = 1 processes in any given model.…”

Up asymmetries from exhilarated composite flavor structures

“…First of all, since only the strange quark is very composite, CPV is predicted to be mostly at work in the D 0 → K + K − channel, a prediction soon to be tested by flavor experiments by measuring the CP asymmetries for each channel individually. To the best of our knowledge this prediction is unique and differs from all other proposed explanation of ∆a CP based on either SM-like CPV sources [66][67][68][69][70][71][72][73][74] or NP contributions from CPV chromomagnetic dipoles [77][78][79][80][81]. Second, assuming a maximal NP phase CPV is expected to be observed in D −D mixing in the near future.…”