GAUGE AND HIGGS BOSONS INSPIRE   JSON PDGID:
S044

${{\mathit Z}}$

$J$ = $1$ 
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${{\mathit Z}}$ MASS [1] $91.1880$ $\pm0.0020$ GeV 
 
${{\mathit Z}}$ WIDTH $2.4955$ $\pm0.0023$ GeV 
 
▸  AVERAGE PARTICLE MULTIPLICITIES IN HADRONIC ${{\mathit Z}}$ DECAY
${{\mathit Z}}$ HADRONIC POLE CROSS SECTION $41.4802$ $\pm0.0325$ nb 
 
▸  ${{\mathit Z}}$ VECTOR COUPLINGS
▸  ${{\mathit Z}}$ AXIAL-VECTOR COUPLINGS
▸  ${{\mathit Z}}$ COUPLINGS TO NEUTRAL LEPTONS
▸  ${{\mathit Z}}$ ASYMMETRY PARAMETERS
▸  TRANSVERSE SPIN CORRELATIONS IN ${{\mathit Z}}$ $\rightarrow$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$
$\mathit A{}^{(0,{{\mathit e}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ $1.45$ $\pm0.25$  
 
$\mathit A{}^{(0,{{\mathit \mu}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ $1.69$ $\pm0.13$  
 
$\mathit A{}^{(0,{{\mathit \tau}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$ $1.88$ $\pm0.17$  
 
$\mathit A{}^{(0,{{\mathit \ell}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ $1.71$ $\pm0.10$  
 
$\mathit A{}^{(0,{{\mathit u}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit u}}{{\overline{\mathit u}}}$ $4$ $\pm7$  
 
$\mathit A{}^{(0,{{\mathit s}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit s}}{{\overline{\mathit s}}}$ $9.8$ $\pm1.1$  
 
$\mathit A{}^{(0,{{\mathit c}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit c}}{{\overline{\mathit c}}}$ $7.07$ $\pm0.35$  
 
$\mathit A{}^{(0,{{\mathit b}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ $9.92$ $\pm0.16$  
 
CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit q}}{{\overline{\mathit q}}}$
 
CHARGE ASYMMETRY IN ${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$
 
sin$^2(\theta _{{\mathrm {eff}}})$ $0.23148$ $\pm0.00013$  
 
▸  ANOMALOUS ${{\mathit Z}}{{\mathit Z}}{{\mathit \gamma}}$ , ${{\mathit Z}}{{\mathit \gamma}}{{\mathit \gamma}}$ , AND ${{\mathit Z}}{{\mathit Z}}{{\mathit V}}$ COUPLINGS
▸  ANOMALOUS ${{\mathit W}}/{{\mathit Z}}$ QUARTIC COUPLINGS
Mode  
Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/
Conf. Level		 P(MeV/c)  
$\Gamma_{1}$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ ($3.3632$ $\pm0.0042$ ) $\%$ 45594
 
$\Gamma_{2}$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ ($3.3662$ $\pm0.0066$ ) $\%$ 45594
 
$\Gamma_{3}$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$ ($3.3696$ $\pm0.0083$ ) $\%$ 45559
 
$\Gamma_{4}$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ [2] ($3.3658$ $\pm0.0023$ ) $\%$  
 
$\Gamma_{5}$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ 45593
 
$\Gamma_{6}$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}{{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ [3] ($4.55$ $\pm0.17$) $ \times 10^{-6}$ 45594
 
$\Gamma_{7}$ invisible ($20.000$ $\pm0.055$ ) $\%$  
 
$\Gamma_{8}$ hadrons ($69.911$ $\pm0.056$ ) $\%$  
 
$\Gamma_{9}$ (${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit u}}}$ + ${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit c}}}$)/2 ($11.6$ $\pm0.6$ ) $\%$  
 
$\Gamma_{10}$ (${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit d}}}$ + ${\mathit {\mathit s}}$ ${\mathit {\overline{\mathit s}}}$ + ${\mathit {\mathit b}}$ ${\mathit {\overline{\mathit b}}}$)/3 ($15.6$ $\pm0.4$ ) $\%$  
 
$\Gamma_{11}$ ${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit c}}}$ ($12.03$ $\pm0.21$ ) $\%$  
 
$\Gamma_{12}$ ${\mathit {\mathit b}}$ ${\mathit {\overline{\mathit b}}}$ ($15.12$ $\pm0.05$ ) $\%$  
 
$\Gamma_{13}$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ ($3.6$ $\pm1.3$) $ \times 10^{-4}$  
 
$\Gamma_{14}$ ${{\mathit g}}{{\mathit g}}{{\mathit g}}$ <1.1 $\%$ CL=95%  
 
$\Gamma_{15}$ ${{\mathit \pi}^{0}}{{\mathit \gamma}}$ $<2.01$ $\times 10^{-5}$ CL=95% 45594
 
$\Gamma_{16}$ ${{\mathit \eta}}{{\mathit \gamma}}$ $<5.1$ $\times 10^{-5}$ CL=95% 45592
 
$\Gamma_{17}$ ${{\mathit \rho}^{0}}{{\mathit \gamma}}$ $<4.0$ $\times 10^{-6}$ CL=95% 45591
 
$\Gamma_{18}$ ${{\mathit \omega}}{{\mathit \gamma}}$ $<3.9$ $\times 10^{-6}$ CL=95% 45591
 
$\Gamma_{19}$ ${{\mathit \eta}^{\,'}{(958)}}{{\mathit \gamma}}$ $<4.2$ $\times 10^{-5}$ CL=95% 45589
 
$\Gamma_{20}$ ${{\mathit \phi}}{{\mathit \gamma}}$ $<7$ $\times 10^{-7}$ CL=95% 45588
 
$\Gamma_{21}$ ${{\mathit \gamma}}{{\mathit \gamma}}$ $<1.46$ $\times 10^{-5}$ CL=95% 45594
 
$\Gamma_{22}$ ${{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$ $<1.52$ $\times 10^{-5}$ CL=95% 45594
 
$\Gamma_{23}$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit \gamma}}$ $<2.2$ $\times 10^{-6}$ CL=95% 45594
 
$\Gamma_{24}$ ${{\mathit \pi}^{\pm}}{{\mathit W}^{\mp}}$ [4] $<7$ $\times 10^{-5}$ CL=95% 10176
 
$\Gamma_{25}$ ${{\mathit \rho}^{\pm}}{{\mathit W}^{\mp}}$ [4] $<8.3$ $\times 10^{-5}$ CL=95% 10151
 
$\Gamma_{26}$ ${{\mathit J / \psi}{(1S)}}$ X ($3.51^{+0.23}_{-0.25}$) $ \times 10^{-3}$ S=1.1   
 
$\Gamma_{27}$ ${{\mathit J / \psi}{(1S)}}{{\mathit \gamma}}$ $<1.2$ $\times 10^{-6}$ CL=95% 45541
 
$\Gamma_{28}$ ${{\mathit \psi}{(2S)}}$ X ($1.60$ $\pm0.29$) $ \times 10^{-3}$  
 
$\Gamma_{29}$ ${{\mathit \psi}{(2S)}}{{\mathit \gamma}}$ $<2.4$ $\times 10^{-6}$ CL=95% 45519
 
$\Gamma_{30}$ ${{\mathit J / \psi}{(1S)}}{{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ 45541
 
$\Gamma_{31}$ ${{\mathit J / \psi}{(1S)}}{{\mathit J / \psi}{(1S)}}$ $<2.2$ $\times 10^{-6}$ CL=95% 45489
 
$\Gamma_{32}$ ${{\mathit \chi}_{{{c1}}}{(1P)}}$ X ($2.9$ $\pm0.7$) $ \times 10^{-3}$  
 
$\Gamma_{33}$ ${{\mathit \chi}_{{{c2}}}{(1P)}}$ X $<3.2$ $\times 10^{-3}$ CL=90%  
 
$\Gamma_{34}$ ${{\mathit \Upsilon}{(1S)}}$ X +${{\mathit \Upsilon}{(2S)}}$ X +${{\mathit \Upsilon}{(3S)}}$ X ($1.0$ $\pm0.5$) $ \times 10^{-4}$  
 
$\Gamma_{35}$ ${{\mathit \Upsilon}{(1S)}}$ X $<4.4$ $\times 10^{-5}$ CL=95%  
 
$\Gamma_{36}$ ${{\mathit \Upsilon}{(1S)}}{{\mathit \gamma}}$ $<1.1$ $\times 10^{-6}$ CL=95% 45103
 
$\Gamma_{37}$ ${{\mathit \Upsilon}{(2S)}}$ X $<1.39$ $\times 10^{-4}$ CL=95%  
 
$\Gamma_{38}$ ${{\mathit \Upsilon}{(2S)}}{{\mathit \gamma}}$ $<1.3$ $\times 10^{-6}$ CL=95% 45043
 
$\Gamma_{39}$ ${{\mathit \Upsilon}{(3S)}}$ X $<9.4$ $\times 10^{-5}$ CL=95%  
 
$\Gamma_{40}$ ${{\mathit \Upsilon}{(3S)}}{{\mathit \gamma}}$ $<2.4$ $\times 10^{-6}$ CL=95% 45006
 
$\Gamma_{41}$ ${{\mathit \Upsilon}{(1,2,3S)}}{{\mathit \Upsilon}{(1,2,3S)}}$ $<1.5$ $\times 10^{-6}$ CL=95%  
 
$\Gamma_{42}$ ${{\mathit K}_S^0}$ ${{\mathit \gamma}}$ $<3.1$ $\times 10^{-6}$ CL=95% 45593
 
$\Gamma_{43}$ ${{\mathit D}^{0}}{{\mathit \gamma}}$ $<4.0$ $\times 10^{-6}$ CL=95% 45575
 
$\Gamma_{44}$ ( ${{\mathit D}^{0}}$ /${{\overline{\mathit D}}^{0}}$) X ($20.7$ $\pm2.0$ ) $\%$  
 
$\Gamma_{45}$ ${{\mathit D}^{\pm}}$ X ($12.2$ $\pm1.7$ ) $\%$  
 
$\Gamma_{46}$ ${{\mathit D}^{*}{(2010)}^{\pm}}$ X [4] ($11.4$ $\pm1.3$ ) $\%$  
 
$\Gamma_{47}$ ${{\mathit D}_{{{s1}}}{(2536)}^{\pm}}$ X ($3.6$ $\pm0.8$) $ \times 10^{-3}$  
 
$\Gamma_{48}$ ${{\mathit D}_{{{sJ}}}{(2573)}^{\pm}}$ X ($5.8$ $\pm2.2$) $ \times 10^{-3}$  
 
$\Gamma_{49}$ ${{\mathit D}^{*'}{(2629)}^{\pm}}$ X searched for  
 
$\Gamma_{50}$ ${{\mathit B}}$ X  
 
$\Gamma_{51}$ ${{\mathit B}^{*}}$ X  
 
$\Gamma_{52}$ ${{\mathit B}^{+}}$ X [5] ($6.08$ $\pm0.13$ ) $\%$  
 
$\Gamma_{53}$ ${{\mathit B}_{{{s}}}^{0}}$ X [5] ($1.59$ $\pm0.13$ ) $\%$  
 
$\Gamma_{54}$ ${{\mathit B}_{{{c}}}^{+}}$ X searched for  
 
$\Gamma_{55}$ ${{\mathit \Lambda}_{{{c}}}^{+}}$ X ($1.54$ $\pm0.33$ ) $\%$  
 
$\Gamma_{56}$ ${{\mathit \Xi}_{{{c}}}^{0}}$ X seen  
 
$\Gamma_{57}$ ${{\mathit \Xi}_{{{b}}}}$ X seen  
 
$\Gamma_{58}$ ${{\mathit b}}$ -baryon X [5] ($1.38$ $\pm0.22$ ) $\%$  
 
$\Gamma_{59}$ anomalous ${{\mathit \gamma}}$ + hadrons [6] $<3.2$ $\times 10^{-3}$ CL=95%  
 
$\Gamma_{60}$ ${{\mathit e}^{+}}{{\mathit e}^{-}}{{\mathit \gamma}}$ [6] $<5.2$ $\times 10^{-4}$ CL=95% 45594
 
$\Gamma_{61}$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{{\mathit \gamma}}$ [6] $<5.6$ $\times 10^{-4}$ CL=95% 45594
 
$\Gamma_{62}$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}{{\mathit \gamma}}$ [6] $<7.3$ $\times 10^{-4}$ CL=95% 45559
 
$\Gamma_{63}$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}{{\mathit \gamma}}{{\mathit \gamma}}$ [7] $<6.8$ $\times 10^{-6}$ CL=95%  
 
$\Gamma_{64}$ ${{\mathit q}}{{\overline{\mathit q}}}{{\mathit \gamma}}{{\mathit \gamma}}$ [7] $<5.5$ $\times 10^{-6}$ CL=95%  
 
$\Gamma_{65}$ ${{\mathit \nu}}{{\overline{\mathit \nu}}}{{\mathit \gamma}}{{\mathit \gamma}}$ [7] $<3.1$ $\times 10^{-6}$ CL=95% 45594
 
$\Gamma_{66}$ ${{\mathit e}^{\pm}}{{\mathit \mu}^{\mp}}$ LF [4] $<2.62$ $\times 10^{-7}$ CL=95% 45594
 
$\Gamma_{67}$ ${{\mathit e}^{\pm}}{{\mathit \tau}^{\mp}}$ LF [4] $<5.0$ $\times 10^{-6}$ CL=95% 45577
 
$\Gamma_{68}$ ${{\mathit \mu}^{\pm}}{{\mathit \tau}^{\mp}}$ LF [4] $<6.5$ $\times 10^{-6}$ CL=95% 45577
 
$\Gamma_{69}$ ${{\mathit p}}{{\mathit e}}$ B|L $<1.8$ $\times 10^{-6}$ CL=95% 45589
 
$\Gamma_{70}$ ${{\mathit p}}{{\mathit \mu}}$ B|L $<1.8$ $\times 10^{-6}$ CL=95% 45589
 
[1] The ${{\mathit Z}}$-boson mass listed here corresponds to a Breit-Wigner resonance parameter. It lies approximately $34$ MeV above the real part of the position of the pole (in the energy-squared plane) in the ${{\mathit Z}}$-boson propagator.
[2] ${{\mathit \ell}}$ indicates each type of lepton (${{\mathit e}}$, ${{\mathit \mu}}$, and ${{\mathit \tau}}$), not sum over them.
[3] Here ${{\mathit \ell}}$ indicates ${{\mathit e}}$ or ${{\mathit \mu}}$.
[4] The value is for the sum of the charge states or particle/antiparticle states indicated.
[5] This value is updated using the product of (i) the ${{\mathit Z}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ fraction from this listing and (ii) the ${{\mathit b}}$-hadron fraction in an unbiased sample of weakly decaying ${{\mathit b}}$-hadrons produced in ${{\mathit Z}}$-decays provided by the Heavy Flavor Averaging Group
[6] See the Particle Listings below for the ${{\mathit \gamma}}$ energy range used in this measurement.
[7] For ${\mathit m}_{\mathrm {{{\mathit \gamma}} {{\mathit \gamma}}}}$ = ($60$ $\pm5$) GeV.