${{\mathit \tau}}$ MASS

INSPIRE   PDGID:
S035M
VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 1776.93 \pm0.09}$ OUR AVERAGE
$1777.09$ $\pm0.08$ $\pm0.11$ 175M 1
ADACHI
2023C
BELL 190 fb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$ = 10.6 GeV
$1776.69$ ${}^{+0.17}_{-0.19}$ $\pm0.15$ 2
ANASHIN
2023A
KEDR (6.7+ 8.5) pb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $3.54 - 3.78$ GeV
$1776.91$ $\pm0.12$ ${}^{+0.10}_{-0.13}$ 1171 3
ABLIKIM
2014D
BES3 23.3 pb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $3.54 - 3.60$ GeV
$1776.68$ $\pm0.12$ $\pm0.41$ 682k 1
AUBERT
2009AK
BABR 423 fb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$=10.6 GeV
$1776.61$ $\pm0.13$ $\pm0.35$ 1
BELOUS
2007
BELL 414 fb${}^{-1}{\it{}E}^{\it{}ee}_{\rm{}cm}$=10.6 GeV
$1775.1$ $\pm1.6$ $\pm1.0$ 13.3k 4
ABBIENDI
2000A
OPAL $1990 - 1995$ LEP runs
$1778.2$ $\pm0.8$ $\pm1.2$
ANASTASSOV
1997
CLEO ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $10.6$ GeV
$1776.96$ ${}^{+0.18}_{-0.21}$ ${}^{+0.25}_{-0.17}$ 65 5
BAI
1996
BES ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $3.54 - 3.57$ GeV
$1776.3$ $\pm2.4$ $\pm1.4$ 11k 6
ALBRECHT
1992M
ARG ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $9.4 - 10.6$ GeV
$1783$ ${}^{+3}_{-4}$ 692 7
BACINO
1978B
DLCO ${\it{}E}^{\it{}ee}_{\rm{}cm}$= 3.1$-$7.4 GeV
• • We do not use the following data for averages, fits, limits, etc. • •
$1776.81$ ${}^{+0.25}_{-0.23}$ $\pm0.15$ 81
ANASHIN
2007
KEDR 6.7 pb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $3.54 - 3.78~$GeV
$1777.8$ $\pm0.7$ $\pm1.7$ 35k 8
BALEST
1993
CLEO Repl. by ANASTASSOV 1997
$1776.9$ ${}^{+0.4}_{-0.5}$ $\pm0.2$ 14 9
BAI
1992
BES Repl. by BAI 1996
1  ADACHI 2023C, AUBERT 2009AK and BELOUS 2007 fit $\tau $ pseudomass spectrum in ${{\mathit \tau}}$ $\rightarrow$ ${{\mathit \pi}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \nu}_{{{\tau}}}}$ decays. Result assumes ${\mathit m}_{{{\mathit \nu}_{{{\tau}}}}}$ = 0.
2  Previously also reported LEVICHEV 2014. Superseedes ANASHIN 2007.
3  ABLIKIM 2014D fit ${\mathit \sigma (}$ ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}{)}$ at different energies near threshold.
4  ABBIENDI 2000A fit ${{\mathit \tau}}$ pseudomass spectrum in ${{\mathit \tau}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{}\leq{}2{{\mathit \pi}^{0}}{{\mathit \nu}_{{{\tau}}}}$ and ${{\mathit \tau}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{}\leq{}1{{\mathit \pi}^{0}}{{\mathit \nu}_{{{\tau}}}}$ decays. Result assumes ${\mathit m}_{{{\mathit \nu}_{{{\tau}}}}}$=0.
5  BAI 1996 fit $\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit \tau}^{+}} {{\mathit \tau}^{-}})}$ at different energies near threshold.
6  ALBRECHT 1992M fit ${{\mathit \tau}}$ pseudomass spectrum in ${{\mathit \tau}^{-}}$ $\rightarrow$ 2 ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \nu}_{{{\tau}}}}$ decays. Result assumes ${\mathit m}_{{{\mathit \nu}_{{{\tau}}}}}$=0.
7  BACINO 1978B value comes from ${{\mathit e}^{\pm}}{{\mathit X}^{\mp}}$ threshold. Published mass 1782 MeV increased by 1 MeV using the high precision ${{\mathit \psi}{(2S)}}$ mass measurement of ZHOLENTZ 1980 to eliminate the absolute SPEAR energy calibration uncertainty.
8  BALEST 1993 fit spectra of minimum kinematically allowed ${{\mathit \tau}}$ mass in events of the type ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$ $\rightarrow$ (${{\mathit \pi}^{+}}{{\mathit n}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{{\tau}}}}$ )(${{\mathit \pi}^{-}}{{\mathit m}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{{\tau}}}}$ ) $\mathit n{}\leq{}$2, $\mathit m{}\leq{}$2, 1${}\leq{}\mathit n+\mathit m{}\leq{}$3. If ${\mathit m}_{{{\mathit \nu}_{{{\tau}}}}}{}\not=$0, result increases by (${{\mathit m}^{2}}_{{{\mathit \nu}_{{{\tau}}}}}$/1100 MeV).
9  BAI 1992 fit $\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit \tau}^{+}} {{\mathit \tau}^{-}})}$ near threshold using ${{\mathit e}}{{\mathit \mu}}$ events.
References