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${\mathit m}_{{{\mathit \Upsilon}{(2S)}}}–{\mathit m}_{{{\mathit \eta}_{{{b}}}{(2S)}}}$

INSPIRE   PDGID:

M200DM

VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT $24.3$ $\pm3.5$ ${}^{+2.8}_{-1.9}$ 26k 1 MIZUK 2012 BELL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ + hadrons • • We do not use the following data for averages, fits, limits, etc. • • $48.7$ $\pm2.3$ $\pm2.1$ $11$ $\pm4$ 2, 3, 4 DOBBS 2012 ${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ hadrons 1  Assuming ${\Gamma}_{{\mathit \eta}_{{{b}}}{(2S)}}$ = 4.9 MeV. Not independent of the corresponding mass measurement. 2  SANDILYA 2013 (Belle Collab.) search for such a state reconstructed in the same 26 exclusive hadronic final states as DOBBS 2012 using a sample of ($157.8$ $\pm3.6$) $ \times 10^{6}{{\mathit \Upsilon}{(2S)}}$ decays or about 17 times larger and find no evidence for a signal. Their 90$\%$ C.L. upper limit on the branching fraction B( ${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \eta}_{{{b}}}{(2S)}}{{\mathit \gamma}}$) ${\times }$ $\sum_{i}$B( ${{\mathit \eta}_{{{b}}}{(2S)}}$ $\rightarrow$ ${{\mathit X}_{{{i}}}}$) $<$ $4.9 \times 10^{-6}$, summed over the exclusive hadronic final states ${{\mathit X}_{{{i}}}}$, is an order of magnitude smaller than that reported by DOBBS 2012. 3  Obtained by analyzing CLEO III data but not authored by the CLEO Collaboration. 4  Assuming ${\Gamma}_{{\mathit \eta}_{{{b}}}{(2S)}}$ = 5 MeV. Not independent of the corresponding mass measurement.

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