nLab Z'-boson



Fields and quanta

fields and particles in particle physics

and in the standard model of particle physics:

force field gauge bosons

scalar bosons

matter field fermions (spinors, Dirac fields)

flavors of fundamental fermions in the
standard model of particle physics:
generation of fermions1st generation2nd generation3d generation
quarks (qq)
up-typeup quark (uu)charm quark (cc)top quark (tt)
down-typedown quark (dd)strange quark (ss)bottom quark (bb)
neutralelectron neutrinomuon neutrinotau neutrino
bound states:
mesonslight mesons:
pion (udu d)
ρ-meson (udu d)
ω-meson (udu d)
ϕ-meson (ss¯s \bar s),
kaon, K*-meson (usu s, dsd s)
eta-meson (uu+dd+ssu u + d d + s s)

charmed heavy mesons:
D-meson (uc u c, dcd c, scs c)
J/ψ-meson (cc¯c \bar c)
bottom heavy mesons:
B-meson (qbq b)
ϒ-meson (bb¯b \bar b)
proton (uud)(u u d)
neutron (udd)(u d d)

(also: antiparticles)

effective particles

hadrons (bound states of the above quarks)


in grand unified theory

minimally extended supersymmetric standard model




dark matter candidates


auxiliary fields



In particle physics the term Z’-boson refers to a hypothetical higher-mass cousin of the Z-boson which is predicted by some models that extend the standard model of particle physics, such as grand unified theories (e.g. Sahoo 06).

The existence of the ZZ' has been proposed as one possible explanation of the apparently observed flavour anomalies (Gauld-Goertz-Haisch 13, D’Ambrosio-Iver-Piccinini-Polosa 19)



Experimental constraints:

  • CMS collaboration, Search for an L μL τL_\mu - L_\tau gauge boson using Z4μZ \to 4\mu events in proton-proton collisions at s=13TeV\sqrt{s} = 13TeV (arXiv:1808.03684)

As arising in GUTs:

  • S. Sahoo, The prediction of mass of ZZ'-boson in an SO(10)SO(10)-based model, Indian J. Phys. 80 (2), 191-194 (2006) (pdf)

In relation to flavour anomalies

As a possible solution to the flavour anomalies:

  • Rhorry Gauld, Florian Goertz, Ulrich Haisch, An explicit Z’-boson explanation of the BK *μ +μ B \to K^\ast \mu^+ \mu^- anomaly, JHEP01(2014)069 (arXiv:1310.1082)

  • Richard H. Benavides, Luis Muñoz, William A. Ponce, Oscar Rodríguez, Eduardo Rojas, Minimal Z Z^\prime models for flavor anomalies (arXiv:1812.05077)

  • Giancarlo D’Ambrosio, A. M. Iyer, F. Piccinini, A.D. Polosa, Confronting BB anomalies with atomic physics (arXiv:1902.00893)

  • P. Ko, Takaaki Nomura, Chaehyun Yu, bsμ +μ b \to s \mu^+ \mu^- anomalies and related phenomenology in U(1) B 3x μL μx τL τU(1)_{B_{3-x_\mu L_\mu - x_\tau L_\tau}} flavor gauge models (arXiv:1902.06107)

  • Joe Davighi, Connecting neutral current BB anomalies with the heaviness of the third family, Contribution to the 2019 QCD session of the 54th Rencontres de Moriond (arXiv:1905.06073)

  • Wolfgang Altmannshofer, Joe Davighi, Marco Nardecchia, Gauging the accidental symmetries of the Standard Model, and implications for the flavour anomalies (arXiv:1909.02021)

  • Rigo Bause, Gudrun Hiller, Tim Höhne, Daniel F. Litim, Tom Steudtner, B-Anomalies from flavorful U(1)U(1)' extensions, safely (arXiv:2109.06201)

    (in view of Higgs field metastability)

  • Disha Bhatia, Nishita Desai, Amol Dighe, Frugal U(1) XU(1)_X models with non-minimal flavor violation for bsb \to s \ell \ell anomalies and neutrino mixing* (arXiv:2109.07093)

Realization in F-theory of GUT-models with Z'-bosons and/or [leptoquarks]] addressing the flavour anomalies and the (g-2) anomalies:

  • Miguel Crispim Romao, Stephen F. King, George K. Leontaris, Non-universal ZZ' from Fluxed GUTs, Physics Letters B Volume 782, 10 July 2018, Pages 353-361 (arXiv:1710.02349)

  • A. Karozas, G. K. Leontaris, I. Tavellaris, N. D. Vlachos, On the LHC signatures of SU(5)×U(1)SU(5) \times U(1)' F-theory motivated models (arXiv:2007.05936)

  • Ben Allanach, U(1) B 3L 2U(1)_{B_3-L_2} Explanation of the Neutral Current BB−Anomalies (arXiv:2009.02197)

  • Andreas Crivellin, Claudio Andreas Manzari, Marcel Alguero, Joaquim Matias, Combined Explanation of the Zbb¯Z \to b \bar b Forward-Backward Asymmetry, the Cabibbo Angle Anomaly, τμνν\tau \to \mu \nu \nu and bs + b \to s \ell^+ \ell^- Data (arXiv:2010.14504)

  • Marcel Algueró, Andreas Crivellin, Claudio Andrea Manzari, Joaquim Matias, Unified Explanation of the Anomalies in Semi-Leptonic BB decays and the WW Mass, Physical Review D (2022) [arXiv:2201.08170]

Last revised on August 8, 2022 at 06:47:46. See the history of this page for a list of all contributions to it.