pdgLive

${{\mathit \gamma}}$ ENERGY IN ${{\mathit \Upsilon}{(2S)}}$ DECAY

VALUE (MeV)

DOCUMENT ID

TECN

COMMENT

$\bf{ 162.5 \pm0.4}$

OUR AVERAGE

$162.56$ $\pm0.19$ $\pm0.42$

CLEO

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit X}}$

$162.0$ $\pm0.8$ $\pm1.2$

CLE2

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}{(1P)}}$

$162.1$ $\pm0.5$ $\pm1.4$

ARG

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ conv. ${{\mathit \gamma}}$ X

$163.8$ $\pm1.6$ $\pm2.7$

CBAL

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ X

$158.0$ $\pm7$ $\pm1$

CLEO

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ conv. ${{\mathit \gamma}}$ X

• • We do not use the following data for averages, fits, limits, etc. • •

$149.4$ $\pm0.7$ $\pm5.0$

CUSB

${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}$ X

References:

PRL 94 032001

Photon Transitions in ${{\mathit \Upsilon}{(2S)}}$ and ${{\mathit \Upsilon}{(3S)}}$ Decays

PR D59 032003

Measurement of the Mass Splittings between the ${\mathit {\mathit b}}{\mathit {\overline{\mathit b}}}{{\mathit \chi}_{{b,J}}{(1P)}}$ States

PL 160B 331

Radiative Decays of the ${{\mathit \Upsilon}{(2S)}}$ into the Three ${{\mathit \chi}_{{b}}}$ States

PRL 54 2195

Observation of Three ${{\mathit p}}$ States in the Radiative Decay of ${{\mathit \Upsilon}{(2S)}}$

PRL 52 799

Observation of Radiative Decays of the ${{\mathit \Upsilon}{(2S)}}$

PRL 51 160

Observation of the Lowest ${\mathit P}{\mathrm -wave}$ ${{\mathit b}}{{\overline{\mathit b}}}$ Bound States

Except where otherwise noted, content of the 2023 Review of Particle Physics is licensed under a Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) license. The publication of the Review of Particle Physics is supported by US DOE, MEXT (Japan), INFN (Italy), JPS and CERN. Individual collaborators receive support for their PDG activities from their respective institutes or funding agencies. © 2023. See LBNL disclaimers.