Constraints on Unparticle Interactions from Invisible Decays of Z, Quarkonia and Neutrinos

Abstract

Unparticles ($\U$) interact weakly with particles. The direct signature of unparticles will be in the form of missing energy. We study constraints on unparticle interactions using totally invisible decay modes of $Z$, vector quarkonia $V$ and neutrinos. The constraints on the unparticle interaction scale $Λ_\U$ are very sensitive to the dimension $d_\U$ of the unparticles. From invisible $Z$ and $V$ decays, we find that with $d_\U$ close to 1 for vector $\U$, the unparticle scale $Λ_\U$ can be more than $10^4$ TeV, and for $d_\U$ around 2, the scale can be lower than one TeV. From invisible neutrino decays, we find that if $d_\U$ is close to 3/2, the scale can be more than the Planck mass, but with $d_\U$ around 2 the scale can be as low as a few hundred GeV. We also study the possibility of using $V (Z)\to γ+ \U$ to constrain unparticle interactions, and find that present data give weak constraints.

12 pages, 4 figures, version to appear in JHEP;

References in corpus (15)

• Unparticle Physics
• Another Odd Thing About Unparticle Physics
• Collider signals in unparticle physics
• Collider Phenomenology of Unparticle Physics
• Deconstruction of Unparticles
• Bounds on Unparticles from the Higgs Sector
• Constraining Unparticle Physics with Cosmology and Astrophysics
• Bounds on Unparticles Couplings to Electrons: from Electron g-2 to Positronium Decays
• Unparticle Physics Effects on D0-anti-D0 Mixing
• Lepton flavor violating processes in unparticle physics
• B \to K(K^*) missing energy in Unparticle physics
• Constraints On Unparticle Physics In Electroweak Gauge Boson Scattering
• Unparticle Physics in DIS
• Unparticle phase effects
• Search for Invisible Decay of the ${\rm Y}(1S)$

Cited by in corpus (32)

• Neutrino Decays over Cosmological Distances and the Implications for Neutrino Telescopes
• Implications of Leptonic Unitarity Violation at Neutrino Telescopes
• Forward-backward asymmetry of top quark in unparticle physics
• Unparticles at heavy flavour scales: CP violating phenomena
• Unparticle physics at the photon collider
• Unparticle Self-Interactions and Their Collider Implications
• Unparticle physics in diphoton production at the CERN LHC
• Cosmological Constraints on Unparticles as Continuous Mass Scalars
• Constraints from Solar and Reactor Neutrinos on Unparticle Long-Range Forces
• Test of unparticle long range forces from perihelion precession of Mercury
• Direct CP violation of $B\to l\nu$ in unparticle physics
• Probing the unparticle signal in $b\to d$ penguin processes
• On the Decay of Unparticles
• Disentangling the Unparticles with polarized beams at e+e- colliders
• Unparticle Realization Through Continuous Mass Scale Invariant Theories
• The large CP phase in B(s) - anti-B(s) mixing and Unparticle Physics
• Unparticle Induced Baryon Number Violating Nucleon Decays
• Unparticle Physics in the Moller Scattering
• Effects of Unparticles on Running of Gauge Couplings
• Probing unparticle theory via lepton flavor violating process $J/\psi \to l{l}^{\prime }$ at BESIII
• Higgs Boson Decays into Single Photon plus Unparticle
• Investigation of $B_{u,d}\to (\pi ,K)\pi$ decays within unparticle physics
• Top off the unparticle
• Unparticle Searches Through Compton Scattering
• Cosmological constraints on unparticle dark matter
• CP-Conserving Unparticle Phase Effects on the Unpolarized and Polarized Direct CP Asymmetry in $b\to d{\ell }^{+}{\ell }^{-}$ Transition
• Unparticle Effects on Unitarity Constraints from Higgs Boson Scattering
• Effect of top quark spin on the unparticle couplings in γγ\to t\bar{t}
• Lectures on neutrino phenomenology
• Unparticle effects in rare (t -> c g g) decay
• Unparticle Effects on Top Quark Pair Production at Photon Collider
• Unparticle Searches Through Low Energy Parity Violating Asymmetry