Pith. sign in

REVIEW 6 cited by

Explaining the B^+to K^+ ν bar{ν} excess via a massless dark photon

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2402.05901 v1 pith:3OEI4SP7 submitted 2024-02-08 hep-ph hep-ex

Explaining the B^+to K^+ ν bar{ν} excess via a massless dark photon

classification hep-ph hep-ex
keywords darkphotonexcessgammamodelscriptscriptstylebelledata
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

The Belle II collaboration has recently observed the rare decay $B^+\to K^+ \nu \bar{\nu}$, finding an excess with respect to the Standard Model prediction. We explore the possibility that the data entails long-distance interactions induced by a massless dark photon, $\gamma_{\scriptscriptstyle{D}}$. This couples at the tree-level to an invisible, dark sector and to the Standard Model via higher-dimensional operators, such as the chromomagnetic-dipole coupling that we use to explain the excess. As the process $B^+\to K^+ \gamma_{\scriptscriptstyle{D}}$ is forbidden by angular momentum conservation, the transition mediated by the off-shell dark photon yields a three-body final state comprising a pair of dark fermions that show as a missing energy continuum in the detector, faking the neutrino signature. We show that the Belle II data is explained for perturbative values of the parameters of the model. This scenario predicts new contributions to the neutral $B$ meson decays $B^0\to K^* \gamma_{\scriptscriptstyle{D}}$, in which the emission of a on-shell dark photon is allowed, yielding a monochromatic missing energy signature. Analogously, an excess due to the emission of a dark photon is predicted for the $B^0_s\to \phi + E_{\rm miss}$ decay that could be scrutinized next at the LHCb experiments.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 6 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Baryon-Meson Sum Rule for $b \to s \nu\bar\nu$

    hep-ph 2026-04 unverdicted novelty 7.0

    An exact sum rule connects branching fractions of Lambda_b -> Lambda nu nubar and B -> K(*) nu nubar decays with coefficients identical to those in the b->c tau semileptonic sum rule.

  2. Radiative generation of chiral vector operators in $b\to s \nu\bar{\nu}$ transition

    hep-ph 2026-01 conditional novelty 6.0

    Minimal one-loop models that generate both chiral vector operators for b→sνν̄ are systematically classified but cannot quantitatively explain the Belle II anomaly.

  3. A Unified Dark Matter Explanation for $\boldsymbol{B^+ \!\to K^+\nu\bar{\nu}}$ and the Super-Kamiokande Antineutrino Excess

    hep-ph 2026-07 conditional novelty 5.0

    A UV-complete complex scalar DM model under gauged U(1)Lμ−Lτ accommodates the SK antineutrino excess, the Belle II B+→K+νν̄ excess, and the DM relic density with one light dark sector.

  4. Dark Matter emission at Belle II and NA62 in Minimal Flavor Violation framework

    hep-ph 2026-01 unverdicted novelty 5.0

    A single nearly degenerate dark matter multiplet in the MFV framework can accommodate either the K+ to pi+ nu nubar or B+ to K+ nu nubar excess but not both simultaneously.

  5. Belle II Constraints on the Non-Minimal Universal Extra Dimensional Model

    hep-ph 2025-09 unverdicted novelty 5.0

    Belle II data on the rare B decay constrains the non-minimal UED model to require the inverse compactification radius to be at least ~900 GeV, while the minimal version yields no bound.

  6. Probing vector- vs scalar-mediator dark-matter scenarios in $B\to (K,K^*) M_X$ decays

    hep-ph 2025-07 accept novelty 5.0

    Scalar and vector dark-matter mediator scenarios in B decays are distinguishable via differential distributions, with data imposing M_V ≲ 3 GeV for vectors but no mass bound for scalars.