Unbroken B-L Symmetry

Abstract

The difference between baryon number B and lepton number L is the only anomaly-free global symmetry of the Standard Model, easily promoted to a local symmetry by introducing three right-handed neutrinos, which automatically make neutrinos massive. The non-observation of any (B-L)-violating processes leads us to scrutinize the case of unbroken gauged B-L; besides Dirac neutrinos, the model contains only three parameters, the gauge coupling strength g', the Stueckelberg mass $M_{Z^{\prime }}$, and the kinetic mixing angle $\chi$. The new force could manifest itself at any scale, and we collect and derive bounds on g' over the entire testable range $M_{Z^{\prime }}$ = 0 - $10^{13}$ eV, also of interest for the more popular case of spontaneously broken B-L or other new light forces. We show in particular that successful Big Bang nucleosynthesis provides strong bounds for masses 10 eV < $M_{Z^{\prime }}$ < 10 GeV due to resonant enhancement of the rate $\bar{f}f\leftrightarrow {\bar{\nu }}_R{\nu }_R$. The strongest limits typically arise from astrophysics and colliders, probing scales $M_{Z^{\prime }}/g^{\prime }$ from TeV up to $10^{10}$ GeV.

8 pages, 3 figures; added reference, matches published version

References in corpus (11)

• New Fixed-Target Experiments to Search for Dark Gauge Forces
• Global fit to three neutrino mixing: critical look at present precision
• New Limits on Hidden Photons from Past Electron Beam Dumps
• Probing a Secluded U(1) at B-factories
• The Minimal Set of Electroweak Precision Parameters
• Search for light massive gauge bosons as an explanation of the $(g-2{)}_{\mu }$ anomaly at MAMI
• A robust upper limit on N_eff from BBN, circa 2011
• Neutron scattering and extra short range interactions
• New weakly-coupled forces hidden in low-energy QCD
• Constraints on new interactions from neutron scattering experiments
• Global constraints on muon-neutrino non-standard interactions

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