PoS - Proceedings of Science
Volume 385 - 10th International Workshop on Charm Physics (CHARM2020) - Parallel programme
Rare and forbidden decays of D0 meson
D.N. Brown
Full text: pdf
Pre-published on: September 26, 2021
Published on:
Abstract
We report the observation of the rare charm decay $D^0 \rightarrow K^-\pi^+e^+e^-$,
a search for nine lepton-number-violating (LNV) and three lepton-flavor-violating (LFV) neutral charm decays of the types $D^0 \rightarrow h^-h'^-l^+l'^+$ and $D^0\rightarrow h^-h'^+l^+l'^-$, where $h$ and $h'$ represent a $K$ or $\pi$ meson, $l$ and $l'$ an electron or muon, and a search for seven lepton-number-violating decays of the type $D^0 \rightarrow X^0e^{\pm}\mu^{\mp}$, where $X^0$ is a $\pi^0,\ K_S^0,\ K^{*0}, \rho^0,\ \phi,\ \omega,\ {\rm or}\ \eta$ meson. The results are based on $468\ {\rm fb}^{-1}$ of $e^+e^-$ collision data collected %at or close to the $\Upsilon(4S)$ resonance
with the \babar\ detector at the SLAC National Accelerator Laboratory. In the invariant mass range $0.675 < m(e^+e^-) < 0.875\ {\rm GeV/c^2}$, we find $\mathcal{B}(D^0\rightarrow K^-\pi^+e^+e^-) = (4.0\pm 0.5\pm0.2\pm0.1)\times 10^{-6}$, where the errors are, respectively, statistical, systematic, and due to uncertainty of the branching fraction of the decay %$D^0\rightarrow K^-\pi^+\pi^+\pi^-$
used for normalization. In other invariant mass regions where long-distance effects are potentially small, we obtain a 90\%
confidence level (C.L.) upper limit on the branching fraction $\mathcal{B}(D^0\rightarrow K^-\pi^+e^+e^-) < 3.1 \times 10^{-6}$. We observe no evidence for any
LFV or LNV modes and establish 90\% C.L. upper limits on the branching fractions in the range $(1.0 - 30.6) \times 10^{-7}$. Individual limits are one to three orders
of magnitude more stringent than previous measurements.
DOI: https://doi.org/10.22323/1.385.0052
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.