# ${{\boldsymbol \chi}_{{c1}}{(1P)}}$ MASS INSPIRE search

VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 3510.67 \pm0.05}$ OUR AVERAGE  Error includes scale factor of 1.2.
$3508.4$ $\pm1.9$ $\pm0.7$ 460 1
 2017 BB
LHCB ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit X}}$ $\rightarrow$ 2( ${{\mathit K}^{+}}{{\mathit K}^{-}}$) ${{\mathit X}}$
$3510.71$ $\pm0.04$ $\pm0.09$ 4.8k 2
 2017 BI
LHCB ${{\mathit \chi}_{{c1}}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$
$3510.30$ $\pm0.14$ $\pm0.16$
 2005 G
BES2 ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{c1}}}$
$3510.719$ $\pm0.051$ $\pm0.019$
 2005 A
E835 ${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}{{\mathit \gamma}}$
$3509.4$ $\pm0.9$
 1999 B
BES ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ X
$3510.60$ $\pm0.087$ $\pm0.019$ 513 3
 1992
E760 ${{\overline{\mathit p}}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}{{\mathit \gamma}}$
$3511.3$ $\pm0.4$ $\pm0.4$ 30
 1986 B
SPEC ${{\overline{\mathit p}}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ X
$3512.3$ $\pm0.3$ $\pm4.0$ 4
 1986
CBAL ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ X
$3507.4$ $\pm1.7$ 91 5
 1982
GOLI 185 ${{\mathit \pi}^{-}}$ ${}^{}\mathrm {Be}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{}^{}\mathrm {A}$
$3510.4$ $\pm0.6$
 1982
CBAL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit J / \psi}}$2 ${{\mathit \gamma}}$
$3510.1$ $\pm1.1$ 254 6
 1980
MRK2 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit J / \psi}}$2 ${{\mathit \gamma}}$
$3509$ $\pm11$ 21
 1979 B
DASP ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit J / \psi}}$2 ${{\mathit \gamma}}$
$3507$ $\pm3$ 6
 1978 B
CNTR ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit J / \psi}}$2 ${{\mathit \gamma}}$
$3505.0$ $\pm4$ $\pm4$ 6, 7
 1978
MRK1 ${{\mathit e}^{+}}{{\mathit e}^{-}}$
$3513$ $\pm7$ 367 6
 1977
CNTR ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ X
• • • We do not use the following data for averages, fits, limits, etc. • • •
$3500$ $\pm10$ 40
 1975
MRK1 Hadrons ${{\mathit \gamma}}$
1  From a fit of the ${{\mathit \phi}}{{\mathit \phi}}$ invariant mass with the width of ${{\mathit \chi}_{{c1}}{(1P)}}$ fixed to the PDG 2016 value.
2  AAIJ 2017BI reports also m(${{\mathit \chi}_{{c2}}}$) $−$ m(${{\mathit \chi}_{{c1}}}$) = $45.39$ $\pm0.07$ $\pm0.03$ MeV.
3  Recalculated by ANDREOTTI 2005A, using the value of ${{\mathit \psi}{(2S)}}$ mass from AULCHENKO 2003 .
4  Using mass of ${{\mathit \psi}{(2S)}}$ = 3686.0 MeV.
5  ${{\mathit J / \psi}{(1S)}}$ mass constrained to 3097 MeV.
6  Mass value shifted by us by amount appropriate for ${{\mathit \psi}{(2S)}}$ mass = 3686 MeV and ${{\mathit J / \psi}{(1S)}}$ mass = 3097 MeV.
References:
 AAIJ 2017BI
PRL 119 221801 ${{\mathit \chi}_{{c1}}}$ and ${{\mathit \chi}_{{c2}}}$ Resonance Parameters with the Decays ${{\mathit \chi}_{{{c1,c2}}}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$
 AAIJ 2017BB
EPJ C77 609 Study of Charmonium Production in hadron Decays and First Evidence for the Decay ${{\mathit B}_{{s}}^{0}}$ $\rightarrow$ ${{\mathit \phi}}{{\mathit \phi}}{{\mathit \phi}}$
 ABLIKIM 2005G
PR D71 092002 Precise Measurement of Spin-Averaged ${{\mathit \chi}_{{cJ}}{(1P)}}$ Mass using Photon Conversions in ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{cJ}}}$
 ANDREOTTI 2005A
NP B717 34 Measurement of the Resonance Parameters of the ${{\mathit \chi}_{{1}}}(1{}^{3}P_{1}$) and ${{\mathit \chi}_{{2}}}(1{}^{3}P_{2}$) States of Charmonium Formed in Antiproton-Proton Annihilations
 BAI 1999B
PR D60 072001 Study of the Hadronic Decays of ${{\mathit \chi}_{{c}}}$ States
 ARMSTRONG 1992
NP B373 35 Study of the ${{\mathit \chi}_{{1}}}$ and ${{\mathit \chi}_{{2}}}$ Charmonium States Formed in ${{\overline{\mathit p}}}{{\mathit p}}$ Annihilations
 BAGLIN 1986B
PL B172 455 Formation of the ${{\mathit \chi}_{{1}}}$ and ${{\mathit \chi}_{{2}}}$ Charmonium Resonances in Antiproton Proton Annihilation and Measurement of their Masses and Total Width
 GAISER 1986
PR D34 711 Charmonium Spectroscopy from Inclusive ${{\mathit \psi}^{\,'}}$ and ${{\mathit J / \psi}}$ Radiative Decays
 LEMOIGNE 1982
PL 113B 509 Measurement of Hadronic Production of the ${{\mathit \chi}_{{1}}{(3507)}^{++}}$ and ${{\mathit \chi}_{{2}}{(3553)}^{++}}$ through Their Radiative Decay to ${{\mathit J / \psi}}$
 OREGLIA 1982
PR D25 2259 Study of the Reaction ${{\mathit \psi}^{\,'}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit J / \psi}}$
 HIMEL 1980
PRL 44 920 Measurement of ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit \psi}}$ Final States in ${{\mathit \psi}^{\,'}}$ Decay
 BRANDELIK 1979B
NP B160 426 Experimental Results on the Decay Sequences ${{\mathit \psi}^{\,'}{(3685)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit P}_{{c}}}$ /${{\mathit \chi}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit J / \psi}}$ , ${{\mathit \gamma}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$, ${{\mathit \gamma}}{{\mathit K}^{+}}{{\mathit K}^{-}}$ and the Decays ${{\mathit \psi}^{\,'}}$ $\rightarrow$ ${{\mathit \eta}}{{\mathit J / \psi}}$ , ${{\mathit \pi}^{0}}{{\mathit J / \psi}}$
 BARTEL 1978B
PL 79B 492 Cascade Radiative Decays of ${{\mathit \psi}^{\,'}{(3684)}}$ and Evidence for a New Intermediate State of Even $\mathit C$ Parity
 TANENBAUM 1978
PR D17 1731 Radiative Decays of the ${{\mathit \psi}^{\,'}{(3684)}}$ into High Mass States
 BIDDICK 1977
PRL 38 1324 Inclusive ${{\mathit \gamma}}$-ray Spectra from ${{\mathit \psi}{(3095)}}$ and ${{\mathit \psi}^{\,'}{(3684)}}$
 TANENBAUM 1975
PRL 35 1323 Observation of an Intermediate State in ${{\mathit \psi}^{\,'}{(3684)}}$ Radiative Cascade Decay