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CITATION

Please use this citation:

S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024) and 2025 update.

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${\mathit {\mathit b}}$-QUARK MASS

INSPIRE JSON (beta) PDGID:

${\mathit {\mathit b}}$-quark mass corresponds to the “running mass” ${{\overline{\mathit m}}_{{{b}}}}({{\mathit \mu}}$ = ${{\overline{\mathit m}}_{{{b}}}}$) in the $\overline{\rm{}MS}$ scheme. We have converted masses in other schemes to the $\overline{\rm{}MS}$ mass using two-loop QCD perturbation theory with ${{\mathit \alpha}_{{{s}}}}({{\mathit \mu}}$ = ${{\overline{\mathit m}}_{{{b}}}}$) = 0ドル.223$ $\pm0.008$. The value 4ドル.18$ ${}^{+0.04}_{-0.03}$ (GeV) for the $\overline{\rm{}MS}$ mass corresponds to 4ドル.78$ $\pm0.06$ GeV for the pole mass, using the two-loop conversion formula. A discussion of masses in different schemes can be found in the “Note on Quark Masses.''

$\overline{\rm{}MS}$ MASS (GeV)	DOCUMENT ID	TECN
$\bf{ 4.183 \pm0.007}$ OUR EVALUATION of $\overline{\rm{}MS}$ Mass. See the ideogram below.
3ドル.94$ ${}^{+0.46}_{-0.40}$	¹	APARISI 2022

THEO

4ドル.202$ $\pm0.021$

²

LATT 4ドル.197$ $\pm0.008$ ³

THEO 4ドル.049$ ${}^{+0.138}_{-0.118}$ ⁴

HERA 4ドル.195$ $\pm0.014$ ⁵

LATT 4ドル.186$ $\pm0.037$ ⁶

THEO 4ドル.197$ $\pm0.022$ ⁷

THEO 4ドル.183$ $\pm0.037$ ⁸

THEO 4ドル.203$ ${}^{+0.016}_{-0.034}$ ⁹

THEO 4ドル.196$ $\pm0.023$ ¹⁰

LATT 4ドル.176$ $\pm0.023$ ¹¹

THEO 4ドル.21$ $\pm0.11$ ¹²

LATT 4ドル.169$ $\pm0.002$ $\pm0.008$ ¹³

THEO 4ドル.166$ $\pm0.043$ ¹⁴

LATT 4ドル.247$ $\pm0.034$ ¹⁵

THEO 4ドル.171$ $\pm0.009$ ¹⁶

THEO 4ドル.29$ $\pm0.14$ ¹⁷

LATT 4ドル.18$ ${}^{+0.05}_{-0.04}$ ¹⁸

THEO 4ドル.186$ $\pm0.044$ $\pm0.015$ ¹⁹

BABR 4ドル.163$ $\pm0.016$ ²⁰

THEO 4ドル.243$ $\pm0.049$ ²¹

BELL • • We do not use the following data for averages, fits, limits, etc. • • 4ドル.184$ $\pm0.011$ ²²

THEO 4ドル.188$ $\pm0.008$ ²³

THEO 4ドル.07$ $\pm0.17$ ²⁴

ZEUS 4ドル.201$ $\pm0.043$ ²⁵

THEO 4ドル.236$ $\pm0.069$ ²⁶

THEO 4ドル.213$ $\pm0.059$ ²⁷

THEO 4ドル.235$ $\pm0.003$ $\pm0.055$ ²⁸

THEO 4ドル.212$ $\pm0.032$ ²⁹

THEO 4ドル.177$ $\pm0.011$ ³⁰

THEO 4ドル.171$ $\pm0.014$ ³¹

THEO 4ドル.164$ $\pm0.023$ ³²

LATT 4ドル.173$ $\pm0.010$ ³³

THEO 5ドル.26$ $\pm1.2$ ³⁴

DLPH 4ドル.42$ $\pm0.06$ $\pm0.08$ ³⁵

LATT 4ドル.347$ $\pm0.048$ $\pm0.08$ ³⁶

LATT 4ドル.164$ $\pm0.025$ ³⁷

THEO 4ドル.19$ $\pm0.40$ ³⁸

DLPH 4ドル.205$ $\pm0.058$ ³⁹

THEO 4ドル.20$ $\pm0.04$ ⁴⁰

THEO 4ドル.19$ $\pm0.06$ ⁴¹

THEO 4ドル.4$ $\pm0.3$ ⁴²

LATT 4ドル.22$ $\pm0.06$ ⁴³

THEO 4ドル.17$ $\pm0.03$ ⁴⁴

THEO 4ドル.22$ $\pm0.11$ ⁴⁵

THEO 4ドル.25$ $\pm0.11$ ⁴⁶

LATT 4ドル.22$ $\pm0.09$ ⁴⁷

THEO 4ドル.19$ $\pm0.05$ ⁴⁸

THEO 4ドル.20$ $\pm0.09$ ⁴⁹

THEO 4ドル.33$ $\pm0.10$ ⁵⁰

LATT 4ドル.24$ $\pm0.10$ ⁵¹

THEO 4ドル.207$ $\pm0.03$ ⁵²

THEO 4ドル.33$ $\pm0.06$ $\pm0.10$ ⁵³

CLEO 4ドル.190$ $\pm0.032$ ⁵⁴

THEO 4ドル.346$ $\pm0.070$ ⁵⁵

THEO

¹ APARISI 2022 determine ${{\mathit m}_{{{b}}}}$ at the Higgs mass, ${{\overline{\mathit m}}_{{{b}}}}({{\mathit m}_{{{H}}}}$) = 2ドル.60$ ${}^{+0.36}_{-0.31}$ GeV from Higgs boson decay rates at the LHC, which is used to obtain ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$).

² HATTON 2021 determine ${{\overline{\mathit m}}_{{{b}}}}$(3 GeV) = 4ドル.513$ $\pm0.026$ GeV using a lattice QCD + quenched QED simulation using the HISQ action and including ${{\mathit n}_{{{f}}}}$ = 2+1+1 flavors of sea quarks, by combining their ${{\overline{\mathit m}}_{{{b}}}}/{{\overline{\mathit m}}_{{{c}}}}$ and ${{\overline{\mathit m}}_{{{c}}}}$ determinations.

³ NARISON 2020 determines the quark mass using QCD Laplace sum rules from the ${{\mathit B}_{{{c}}}}$ mass, combined with previous determinations of the QCD condensates and ${\mathit {\mathit c}}$ and ${\mathit {\mathit b}}$ masses.

⁴ ABRAMOWICZ 2018 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) = 4ドル.049$ ${}^{+0.104}_{-0.109}{}^{+0.090}_{-0.032}{}^{+0.001}_{-0.031}$ from the production of ${\mathit {\mathit b}}$ quarks in ${{\mathit e}}{{\mathit p}}$ collisions at HERA using combined H1 and ZEUS data. The experimental/fitting errors, and those from modeling and parameterization have been combined in quadrature.

⁵ BAZAVOV 2018 determine the ${\mathit {\mathit b}}$ mass using a lattice computation with staggered fermions and five active quark flavors.

⁶ PESET 2018 determine ${{\overline{\mathit m}}_{{{c}}}}({{\overline{\mathit m}}_{{{c}}}}$) and ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) using an N3LO calculation of the ${{\mathit \eta}_{{{c}}}},ドル ${{\mathit \eta}_{{{b}}}}$ and ${{\mathit B}_{{{c}}}}$ masses.

⁷ KIYO 2016 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from the ${{\mathit \Upsilon}{(1S)}}$ mass at order ${{\mathit \alpha}_{{{s}}}^{3}}$ (N3LO).

⁸ ALBERTI 2015 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from fits to inclusive ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{c}}}}{{\mathit e}}{{\overline{\mathit \nu}}}$ decay. They also find ${{\mathit m}}{}^{{\mathrm {kin}}}_{b}$(1 GeV) = 4ドル.553$ $\pm0.020$ GeV.

⁹ BENEKE 2015 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) using sum rules for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ hadrons at order N3LO including finite ${\mathit m}_{{{\mathit c}}}$ effects. They find ${{\mathit m}}{}^{{\mathrm {PS}}}_{b}$(2 GeV) = 4ドル.532$ ${}^{+0.013}_{-0.039}$ GeV, and ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) = 4ドル.193$ ${}^{+0.022}_{-0.035}$ GeV. The value quoted is obtained using the four-loop conversion given in BENEKE 2016.

¹⁰ COLQUHOUN 2015 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from moments of the vector current correlator computed with a lattice simulation using the NRQCD action.

¹¹ DEHNADI 2015 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) using sum rules for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ hadrons at order ${{\mathit \alpha}_{{{s}}}^{3}}$ (N3LO), and fitting to both experimental data and lattice results.

¹² BERNARDONI 2014 determine ${{\mathit m}_{{{b}}}}$ from ${{\mathit n}_{{{f}}}}$ = 2 lattice calculations using heavy quark effective theory non-perturbatively renormalized and matched to QCD at 1/$\mathit m$ order.

¹³ PENIN 2014 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) = 4ドル.169$ $\pm0.008$ $\pm0.002$ $\pm0.002$ using an estimate of the order ${{\mathit \alpha}_{{{s}}}^{3}}{\mathit {\mathit b}}$-quark vacuum polarization function in the threshold region, including finite ${\mathit m}_{{{\mathit c}}}$ effects. The errors of $\pm0.008$ from theoretical uncertainties, and $\pm0.002$ from ${{\mathit \alpha}_{{{s}}}}$ have been combined in quadrature.

¹⁴ LEE 2013O determines ${\mathit m}_{{{\mathit b}}}$ using lattice calculations of the ${{\mathit \Upsilon}}$ and ${{\mathit B}_{{{s}}}}$ binding energies in NRQCD, including three light dynamical quark flavors. The quark mass shift in NRQCD is determined to order ${{\mathit \alpha}_{{{s}}}^{2}},ドル with partial ${{\mathit \alpha}_{{{s}}}^{3}}$ contributions.

¹⁵ LUCHA 2013 determines ${\mathit m}_{{{\mathit b}}}$ from QCD sum rules for heavy-light currents using the lattice value for ${{\mathit f}_{{{B}}}}$ of 191ドル.5$ $\pm7.3$ GeV.

¹⁶ BODENSTEIN 2012 determine ${\mathit m}_{{{\mathit b}}}$ using sum rules for the vector current correlator and the ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Q}}{{\overline{\mathit Q}}}$ total cross-section.

¹⁷ DIMOPOULOS 2012 determine quark masses from a lattice computation using ${{\mathit n}_{{{f}}}}$ = 2 dynamical flavors of twisted mass fermions.

¹⁸ LASCHKA 2011 determine the ${{\mathit b}}$ mass from the charmonium spectrum. The theoretical computation uses the heavy potential to order 1/${\mathit m}_{{{\mathit Q}}}$ obtained by matching the short-distance perturbative result onto lattice QCD result at larger scales.

¹⁹ AUBERT 2010A determine the ${\mathit {\mathit b}}$- and ${\mathit {\mathit c}}$-quark masses from a fit to the inclusive decay spectra in semileptonic ${{\mathit B}}$ decays in the kinetic scheme (and convert it to the $\overline{\rm{}MS}$ scheme).

²⁰ CHETYRKIN 2009 determine ${\mathit m}_{{{\mathit c}}}$ and ${\mathit m}_{{{\mathit b}}}$ from the ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Q}}{{\overline{\mathit Q}}}$ cross-section and sum rules, using an order ${{\mathit \alpha}_{{{s}}}^{3}}$ (N3LO) computation of the heavy quark vacuum polarization.

²¹ SCHWANDA 2008 measure moments of the inclusive photon spectrum in ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{s}}}}{{\mathit \gamma}}$ decay to determine ${{\mathit m}_{{{b}}}^{1S}}$. We have converted this to $\overline{\rm{}MS}$ scheme.

²² NARISON 2018A determines ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) as a function of ${{\mathit \alpha}_{{{s}}}}$ using QCD exponential sum rules and their ratios evaluated at the optimal scale $\mu $ = 9.5 GeV at N2LO-N3LO of perturbative QCD and including condensates up to dimension 6ドル - 8$ in the (axial-)vector and (pseudo-)scalar bottomonium channels.

²³ NARISON 2018B determines ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) using QCD vector moment sum rules and their ratios at N2LO-N3LO of perturbative QCD and including condensates up to dimension 8.

²⁴ ABRAMOWICZ 2014A determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) = 4ドル.07$ $\pm0.14$ ${}^{+0.01}_{-0.07}{}^{+0.05}_{-0.00}{}^{+0.08}_{-0.05}$ from the production of ${\mathit {\mathit b}}$ quarks in ${{\mathit e}}{{\mathit p}}$ collisions at HERA. The errors due to fitting, modeling, PDF parameterization, and theoretical QCD uncertainties due to the values of ${{\mathit \alpha}_{{{s}}}},ドル ${{\mathit m}_{{{c}}}},ドル and the renormalization scale $\mu $ have been combined in quadrature.

²⁵ AYALA 2014A determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from the ${{\mathit \Upsilon}{(1S)}}$ mass computed to N3LO order in perturbation theory using a renormalon subtracted scheme.

²⁶ NARISON 2013 determines ${\mathit m}_{{{\mathit b}}}$ using QCD spectral sum rules to order ${{\mathit \alpha}_{{{s}}}^{2}}$ (NNLO) and including condensates up to dimension 6.

²⁷ NARISON 2013A determines ${\mathit m}_{{{\mathit b}}}$ using HQET sum rules to order ${{\mathit \alpha}_{{{s}}}^{2}}$ (NNLO) and the ${{\mathit B}}$ meson mass and decay constant.

²⁸ HOANG 2012 determine ${\mathit m}_{{{\mathit b}}}$ using non-relativistic sum rules for the ${{\mathit \Upsilon}}$ system at order ${{\mathit \alpha}_{{{s}}}^{2}}$ (NNLO) with renormalization group improvement.

²⁹ NARISON 2012 determines ${\mathit m}_{{{\mathit b}}}$ using exponential sum rules for the vector current correlator to order ${{\mathit \alpha}_{{{s}}}^{3}},ドル including the effect of gluon condensates up to dimension eight.

³⁰ Determines ${\mathit m}_{{{\mathit b}}}$ to order ${{\mathit \alpha}_{{{s}}}^{3}}$ (N3LO), including the effect of gluon condensates up to dimension eight combining the methods of NARISON 2012 and NARISON 2012A.

³¹ NARISON 2012A determines ${\mathit m}_{{{\mathit b}}}$ using sum rules for the vector current correlator to order ${{\mathit \alpha}_{{{s}}}^{3}},ドル including the effect of gluon condensates up to dimension eight.

³² MCNEILE 2010 determines ${\mathit m}_{{{\mathit b}}}$ by comparing order ${{\mathit \alpha}_{{{s}}}^{3}}$ (N3LO) perturbative results for the pseudo-scalar current to lattice simulations with ${{\mathit n}_{{{f}}}}$ = 2+1 sea-quarks by the HPQCD collaboration.

³³ NARISON 2010 determines ${\mathit m}_{{{\mathit b}}}$ from ratios of moments of vector current correlators computed to order ${{\mathit \alpha}_{{{s}}}^{3}}$ and including the dimension-six gluon condensate. These values are taken from the erratum to that reference.

³⁴ ABDALLAH 2008D determine ${{\overline{\mathit m}}_{{{b}}}}({{\mathit M}_{{{Z}}}}$) = 3ドル.76$ $\pm1.0$ GeV from a leading order study of four-jet rates at LEP.

³⁵ GUAZZINI 2008 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from a quenched lattice simulation of heavy meson masses. The $\pm0.08$ is an estimate of the quenching error.

³⁶ DELLA-MORTE 2007 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from a computation of the spin-averaged ${{\mathit B}}$ meson mass using quenched lattice HQET at order 1/${{\mathit m}}$. The $\pm0.08$ is an estimate of the quenching error.

³⁷ KUHN 2007 determine ${{\overline{\mathit m}}_{{{b}}}}({{\mathit \mu}}$ = 10 GeV) = 3ドル.609$ $\pm0.025$ GeV and ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from a four-loop sum-rule computation of the cross-section for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ hadrons in the bottom threshold region.

³⁸ ABDALLAH 2006D determine ${\mathit m}_{{{\mathit b}}}({{\mathit M}_{{{Z}}}}$) = 2ドル.85$ $\pm0.32$ GeV from ${{\mathit Z}}$-decay three-jet events containing a ${{\mathit b}}$-quark.

³⁹ BOUGHEZAL 2006 $\overline{\rm{}MS}$ scheme result comes from the first moment of the hadronic production cross-section to order ${{\mathit \alpha}_{{{s}}}^{3}}$.

⁴⁰ BUCHMUELLER 2006 determine ${{\mathit m}_{{{b}}}}$ and ${{\mathit m}_{{{c}}}}$ by a global fit to inclusive ${{\mathit B}}$ decay spectra.

⁴¹ PINEDA 2006 $\overline{\rm{}MS}$ scheme result comes from a partial NNLL evaluation (complete at order ${{\mathit \alpha}_{{{s}}}^{2}}$ (NNLO)) of sum rules of the bottom production cross-section in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ annihilation.

⁴² GRAY 2005 determines ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from a lattice computation of the ${{\mathit \Upsilon}}$ spectrum. The simulations have 2+1 dynamical light flavors. The ${{\mathit b}}$ quark is implemented using NRQCD.

⁴³ AUBERT 2004X obtain ${\mathit m}_{{{\mathit b}}}$ from a fit to the hadron mass and lepton energy distributions in semileptonic ${{\mathit B}}$ decay. The paper quotes values in the kinetic scheme. The $\overline{\rm{}MS}$ value has been provided by the BABAR collaboration.

⁴⁴ BAUER 2004 determine ${\mathit m}_{{{\mathit b}}},ドル ${\mathit m}_{{{\mathit c}}}$ and ${\mathit m}_{{{\mathit b}}}−{\mathit m}_{{{\mathit c}}}$ by a global fit to inclusive ${{\mathit B}}$ decay spectra.

⁴⁵ HOANG 2004 determines ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from moments at order ${{\mathit \alpha}_{{{s}}}^{2}}$ of the bottom production cross-section in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ annihilation.

⁴⁶ MCNEILE 2004 use lattice QCD with dynamical light quarks and a static heavy quark to compute the masses of heavy-light mesons.

⁴⁷ BAUER 2003 determine the b quark mass by a global fit to ${{\mathit B}}$ decay observables. The experimental data includes lepton energy and hadron invariant mass moments in semileptonic ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{c}}}}{{\mathit \ell}}{{\mathit \nu}_{{{{{\mathit \ell}}}}}}$ decay, and the inclusive photon spectrum in ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{s}}}}{{\mathit \gamma}}$ decay. The theoretical expressions used are of order 1/m${}^{3},ドル and $\alpha {}^{2}_{s}\beta _{0}$.

⁴⁸ BORDES 2003 determines m$_{b}$ using QCD finite energy sum rules to order $\alpha {}^{2}_{s}$.

⁴⁹ CORCELLA 2003 determines ${{\overline{\mathit m}}_{{{b}}}}$ using sum rules computed to order $\alpha {}^{2}_{s}$. Includes charm quark mass effects.

⁵⁰ DEDIVITIIS 2003 use a quenched lattice computation of heavy-heavy and heavy-light meson masses.

⁵¹ EIDEMULLER 2003 determines ${{\overline{\mathit m}}_{{{b}}}}$ and ${{\overline{\mathit m}}_{{{c}}}}$ using QCD sum rules.

⁵² ERLER 2003 determines ${{\overline{\mathit m}}_{{{b}}}}$ and ${{\overline{\mathit m}}_{{{c}}}}$ using QCD sum rules. Includes recent BES data.

⁵³ MAHMOOD 2003 determines ${{\mathit m}}{}^{1S}_{b}$ by a fit to the lepton energy moments in ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{c}}}}{{\mathit \ell}}{{\mathit \nu}_{{{{{\mathit \ell}}}}}}$ decay. The theoretical expressions used are of order 1/m${}^{3}$ and $\alpha {}^{2}_{s}\beta _{0}$. We have converted their result to the $\overline{\rm{}MS}$ scheme.

⁵⁴ BRAMBILLA 2002 determine ${{\overline{\mathit m}}_{{{b}}}}({{\overline{\mathit m}}_{{{b}}}}$) from a computation of the ${{\mathit \Upsilon}{(1S)}}$ mass to order ${{\mathit \alpha}_{{{s}}}^{4}},ドル including finite ${{\mathit m}_{{{c}}}}$ corrections.

⁵⁵ PENIN 2002 determines ${{\overline{\mathit m}}_{{{b}}}}$ from the spectrum of the ${{\mathit \Upsilon}}$ system.

${\mathit {\mathit b}}$-QUARK $\overline{\rm{}MS}$ MASS (GeV) References

Except where otherwise noted, content of the 2025 Review of Particle Physics is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) license. The publication of the Review of Particle Physics is supported by US DOE, MEXT and KEK (Japan), INFN (Italy) and CERN. Individual collaborators receive support for their PDG activities from their respective institutes or funding agencies. © 2025. See LBNL disclaimers.