# ${{\boldsymbol \pi}_{{2}}{(1670)}}$ MASS INSPIRE search

VALUE (MeV) EVTS DOCUMENT ID TECN CHG  COMMENT
$\bf{ 1670.6 {}^{+2.9}_{-1.2}}$ OUR AVERAGE  Error includes scale factor of 1.3.
$1642$ ${}^{+12}_{-1}$ 46M 1
 2018 B
COMP 190 ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit p}}$
$1749$ $\pm10$ $\pm100$ 145k
 2005
B852 18 ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit p}}$
$1676$ $\pm3$ $\pm8$ 2
 2002
B852 18.3 ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}{{\mathit p}}$
$1685$ $\pm10$ $\pm30$
 2001
450 ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}_{{f}}}$3 ${{\mathit \pi}^{0}}{{\mathit p}_{{s}}}$
$1687$ $\pm9$ $\pm15$
 1999
VES 37 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit A}^{*}}$
$1669$ $\pm4$
 1998 B
450 ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}_{{f}}}{{\mathit \rho}}$ ${{\mathit \pi}}{{\mathit p}_{{s}}}$
$1670$ $\pm4$
 1998 B
450 ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}_{{f}}}{{\mathit f}_{{2}}{(1270)}}{{\mathit \pi}}$ ${{\mathit p}_{{s}}}$
$1690$ $\pm14$ 3
 1994
VES 37 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}{{\mathit A}}$
$1710$ $\pm20$ 700
 1987
SIGM - 50 ${{\mathit \pi}^{-}}$ ${}^{}\mathrm {Cu}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{{\mathit \pi}^{-}}{}^{}\mathrm {Cu}$
$1676$ $\pm6$ 3
 1981
OMEG - 12 ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ 3 ${{\mathit \pi}}{{\mathit p}}$
$1657$ $\pm14$ 4, 3
 1980 D
SPEC - 63$-$94 ${{\mathit \pi}}$ ${{\mathit p}}$ $\rightarrow$ 3 ${{\mathit \pi}}$ X
$1662$ $\pm10$ 2000 3
 1977
HBC + 15 ${{\mathit \pi}^{+}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}$3 ${{\mathit \pi}}$
• • • We do not use the following data for averages, fits, limits, etc. • • •
$1658$ $\pm3$ ${}^{+24}_{-8}$ 420k 5
 2010
COMP 190 ${{\mathit \pi}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit P}}{{\mathit b}^{\,'}}$
$1730$ $\pm20$ 6
 1995 B
VES 36 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}{{\mathit A}}$
$1742$ $\pm31$ $\pm49$
 1990
CBAL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$
$1624$ $\pm21$ 2
 1985
SPEC 40 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit A}}$
$1622$ $\pm35$ 7
 1985
SPEC 40 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit A}}$
$1693$ $\pm28$ 8
 1985
SPEC 40 ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit A}}$
$1710$ $\pm20$ 9
 1981 B
SPEC - 63,94 ${{\mathit \pi}^{-}}{{\mathit p}}$
$1660$ $\pm10$ 3
 1973
HBC - 5$-$25 ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \pi}_{{2}}}$
1  Statistical error negligible.
2  From ${{\mathit f}_{{2}}{(1270)}}{{\mathit \pi}}$ decay.
3  From a fit to $\mathit J{}^{P} = 2{}^{-}{\mathit S}{\mathrm -wave}$ ${{\mathit f}_{{2}}{(1270)}}{{\mathit \pi}}$ partial wave.
4  Clear phase rotation seen in 2${}^{–}\mathit S$, 2${}^{–}\mathit P$, 2${}^{–}\mathit D$ waves. We quote central value and spread of single-resonance fits to three channels.
5  Superseded by AGHASYAN 2018B.
6  $J^{PC}$ ambiguous.
7  From ${{\mathit \rho}}{{\mathit \pi}}$ decay.
8  From ${{\mathit \sigma}}{{\mathit \pi}}$ decay.
9  From a two-resonance fit to four 2${}^{–}0{}^{+}$ waves. This should not be averaged with all the single resonance fits.

${{\mathit \pi}_{{2}}{(1670)}}$ mass (MeV)
References:
 AGHASYAN 2018B
PR D98 092003 Light isovector resonances in $\pi^- p \to \pi^-\pi^-\pi^+ p$ at 190 GeV/${\it c}$
 ALEKSEEV 2010
PRL 104 241803 Observation of a $\mathit J{}^{PC} = 1-+$ Exotic Resonance in Diffractive Dissociation of 190 GeV/$\mathit c$ ${{\mathit \pi}^{-}}$ into ${{\mathit \pi}^{-}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}$
 LU 2005
PRL 94 032002 Exotic Meson Decay to ${{\mathit \omega}}{{\mathit \pi}^{0}}{{\mathit \pi}^{-}}$
 CHUNG 2002
PR D65 072001 Exotic and ${\mathit {\mathit q}}{\mathit {\overline{\mathit q}}}$ Resonances in the ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$ System Produced in ${{\mathit \pi}^{-}}{{\mathit p}}$ Collisions at 18-GeV/$\mathit c$
 BARBERIS 2001
PL B507 14 A Study of the Centrally Produced ${{\mathit \pi}^{0}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$ Channel in ${{\mathit p}}{{\mathit p}}$ Interactions at 450 ${\mathrm {GeV/}}\mathit c$
 AMELIN 1999
PAN 62 445 Investigation of the Reaction ${{\mathit \pi}^{-}}$ ${+}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{+}$ ${{\mathit A}}$
 BARBERIS 1998B
PL B422 399 A Study of the Centrally Produced ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ Channel in ${{\mathit p}}{{\mathit p}}$ Interactions at 450 ${\mathrm {GeV/}}\mathit c$
 AMELIN 1995B
PL B356 595 Study of Resonance Production in Diffractive Reaction ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}{{\mathit A}}$
 BERDNIKOV 1994
PL B337 219 Study of the Reaction ${{\mathit \pi}^{-}}$ ${{\mathit A}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}{{\mathit A}}$ at 37 ${\mathrm {GeV/}}\mathit c$
 ANTREASYAN 1990
ZPHY C48 561 First Observation of the Reaction ${{\mathit \gamma}}$ ${{\mathit \gamma}}$ $\rightarrow$ ${{\mathit \pi}_{{2}}{(1670)}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$
 ANTIPOV 1987
EPL 4 403 Direct Observation of ${{\mathit \pi}_{{2}}{(1670)}}$ in the ${{\mathit \rho}}{{\mathit \pi}^{-}}$ System
 BELLINI 1985
SJNP 41 781 $2{}^{-}{}^{}$ Resonances in the ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$ Systems
 DAUM 1981B
NP B182 269 Diffractive Production of 3${{\mathit \pi}}$ States at 63 and 94 GeV
 EVANGELISTA 1981
NP B178 197 Results from a ${{\mathit \pi}^{-}}{{\mathit p}}$ Slow Proton Trigger Experiment at 12 ${\mathrm {GeV/}}\mathit c$
 DAUM 1980D
PL 89B 285 3${{\mathit \pi}}$ Resonances in $2{}^{-}{}^{}$ Partial Waves
 BALTAY 1977
PRL 39 591 Diffractive and Nondiffractive ${{\mathit A}_{{1}}}$, ${{\mathit A}_{{3}}}$ and ${{\mathit A}_{{4}}}$ Production in ${{\mathit \pi}^{+}}{{\mathit p}}$ Interactions at 15 ${\mathrm {GeV/}}\mathit c$
 ASCOLI 1973
PR D7 669 Spin Parity Analysis of the ${{\mathit A}_{{3}}}$