Displaced or invisible? ALPs from $B$ decays at Belle II

Abstract

At colliders, neutral long-lived particles can be detected through displaced decay products or as missing energy. Which search strategy is better depends on the particle's decay length just as on the detector properties. We investigate the complementarity of displaced and invisible signatures for the Belle II experiment. Focusing on axion-like particles $a$ produced from meson decays, we present a new search strategy for two-body decays $B^{+}\to K^{+}a,a\to E/$ with missing energy $E/$. With $50$ab${}^{-1}$ of data, Belle II can probe light invisible resonances with branching ratio $\mathcal{B}(B^{+}\to K^{+}a)\gtrsim 10^{-7}$ and decay length $c{\tau }_a\gtrsim 1$m. For axion-like particles, we expect the sensitivity of $B^{+}\to K^{+}E/$ to small couplings to improve by up to two orders of magnitude compared to previous searches at collider and fixed-target experiments. For sub-GeV particles, $B^{+}\to K^{+}E/$ at Belle II and searches at beam-dump experiments are most sensitive; for heavier particles, searches for displaced vertices at Belle II, long-lived particle experiments at the LHC, and future fixed-target experiments can probe the smallest couplings.

arXiv comment30 pages, 12 figures, 1 table

References in corpus (47)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• An Introduction to PYTHIA 8.2
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• Constraints on Dark Matter from Colliders
• Astrophysical Axion Bounds
• Collider Probes of Axion-Like Particles
• Maverick dark matter at colliders
• Feebly-Interacting Particles:FIPs 2020 Workshop Report
• Revised constraints and Belle II sensitivity for visible and invisible axion-like particles
• Searching for axion-like particles with ultra-peripheral heavy-ion collisions
• New Exclusion Limits for Dark Gauge Forces from Beam-Dump Data
• The Low-Energy Effective Theory of Axions and ALPs
• Flavor probes of axion-like particles
• Decay and Detection of a Light Scalar Boson Mixing with the Higgs
• $B\to P$ and $B\to V$ Form Factors from $B$-Meson Light-Cone Sum Rules beyond Leading Twist
• The Belle II Core Software
• Axion-Like Particles at Future Colliders
• Quark Flavor Phenomenology of the QCD Axion
• On a Light Spinless Particle Coupled to Photons
• A New Flavor of Searches for Axion-Like Particles
• Is there a supernova bound on axions?
• Multi-lepton Signatures of a Hidden Sector in Rare B Decays
• Decay photons from the ALP burst of type-II supernovae
• The Search for Feebly-Interacting Particles
• b-physics signals of the lightest CP-odd Higgs in the NMSSM at large tan beta
• Robust cosmological constraints on axion-like particles
• Running in the ALPs
• Flavor constraints on electroweak ALP couplings
• New Bounds for Axions and Axion-Like Particles with keV-GeV Masses
• The High-Energy Frontier of the Intensity Frontier: Closing the Dark Photon, Inelastic Dark Matter, and Muon g-2 Windows
• Constraining the Axion Portal with B -> K l+ l-
• Heavy axion-like particles and core-collapse supernovae: constraints and impact on the explosion mechanism
• Constraints on a very light CP-odd Higgs of the NMSSM and other axion-like particles
• Probing dark sectors with long-lived particles at BELLE II
• Invisible and displaced dark matter signatures at Belle II
• Model-independent bounds on light pseudoscalars from rare B-meson decays
• Minimal Flavor Violation with Axion-like Particles
• Track Finding at Belle II
• Supernova bound on Axion-Like Particles coupled with electrons
• Cosmological constraints on decaying axion-like particles: a global analysis
• Long-lived Dark Higgs and Inelastic Dark Matter at Belle II
• Heavy QCD Axion at Belle II: Displaced and Prompt Signals
• Cosmological Implications of Axion-Matter Couplings
• Unleashing the full power of LHCb to probe Stealth New Physics
• Complete theory of radiative corrections to $K_{\ell 3}$ decays and the $V_{us}$ update
• Higgs portal to dark matter and $B\to K^{(\ast )}$ decays
• $\tau \to \ell +$ invisible through invisible-savvy collider variables

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