English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The LHCb Collaboration has recently reported the discovery of direct CPviolation in combined $D^0 \to K^+ K^-$ and $D^0 \to \pi^+ \pi^-$ decay modesat the $5.3 \sigma$ level. Assuming U-spin symmetry (i.e., $d \leftrightarrows$ interchange symmetry) for the strong-interaction parts of these twochannels, we find that their corresponding direct CP-violating asymmetries are${\cal A}^{}_{\rm CP} (K^+ K^-) \simeq \left(-7.7 \pm 1.5\right) \times10^{-4}$ and ${\cal A}^{}_{\rm CP} (\pi^+ \pi^-) \simeq \left(7.7 \pm1.5\right) \times 10^{-4}$. The CP-forbidden transition $e^+ e^- \toD^0\bar{D}^0 \to \left(K^+ K^-\right)^{}_D \left(\pi^+ \pi^-\right)^{}_D$ onthe $\psi(3770)$ resonance is therefore expected to have a rate of ${\calO}(10^{-10})$ or smaller under U-spin symmetry, and it can be observed at ahigh-luminosity super-$\tau$-charm factory if at least $10^{10}$ pairs ofcoherent $D^0$ and $\bar{D}^0$ events are accumulated.

A U-spin prediction for the CP-forbidden transition $e^+ e^- \to D^0\bar{D}^0 \to (K^+ K^-)_D (\pi^+ \pi^-)_D$