Study of dipion transitions amongΥ(3S),Υ(2S), and

D. Cronin-Hennessy¹,

K. Y. Gao²,

J. Hietala³

et al.

Abstract

We present measurements of decay matrix elements for hadronic transitions of the form nS ! mS, where n; m 3; 1; 2; 1; 3; 2. We reconstruct charged and neutral pion modes with the final state Upsilon decaying to either ÿ or e e ÿ . Dalitz plot distributions for the 12 decay modes are fit individually as well as jointly assuming isospin symmetry, thereby measuring the matrix elements of the decay amplitude. We observe and account for the anomaly previously noted in the dipion invariant mass distribution for the 3S ! 1S transition and obtain good descriptions of the dynamics of the decay using the most general decay amplitude allowed by partial conservation of the axial-vector current considerations. The fits further indicate that the 2S ! 1S and 3S ! 2S transitions also show the presence of terms in the decay amplitude that were previously ignored, although at a relatively suppressed level.

Search for the Xb and other hidden-beauty states in the π+πAad1, Abbott2, Abdallah3 et al. 2015Physics Letters BSelf Cite261100View full textAdd to dashboardCite

“…Upper limits are evaluated at the 95% confidence level using the CL S method by implementing asymptotic formulae for the q μ statistic [41]. The results (Fig.…”

“…At each mass, a simultaneous fit to the analysis bins is performed in a range m ± 8σ ec , where σ ec (m) is the width of the narrow signal component in the endcap: the window varies from ±72 MeV at 10 GeV to ±224 MeV at 10.9 GeV; 3 Here, a narrow state refers to one whose natural width is much smaller than the experimental resolution. At each mass, the p-value is extracted using the asymptotic formula [41] for the q 0 statistic, a modification of the standard likelihood ratio (see Fig. 3).…”

“…[41], the expected significance for a relative production rate R = 6.56% (the value of the analogous quantity for the X(3872) [5]) is calculated as a function of mass, shown as the dashed blue line in Fig. 3; it exceeds 5σ for m 10.12 GeV.…”

Effect of the KK¯ and ηη channels and interference phenomena in the two-pion and Surovtsev1, Bydžovský2, Gutsche3 et al. 2018Phys. Rev. D

“…also in [6]). For Υ(2S) → Υ(1S)(π + π − and π 0 π 0 ) data were used from ARGUS [13], CLEO [14], CUSB [15], and Crystal Ball [16] Collaborations; for Υ(3S) → Υ(1S)(π + π − , π 0 π 0 ) and Υ(3S) → Υ(2S)(π + π − , π 0 π 0 ) -from CLEO [22,23]; for Υ(4S) → Υ(1S, 2S)π + π − -from BABAR [18] and Belle [17]; for Υ(5S) → Υ(1S, 2S, 3S)(π + π − , π 0 π 0 ) -from Belle Collaboration [17,24].…”

Chromopolarizabilities of bottomonia from the ϒ(2S,3S,4S)→ϒ(1

“…The solid squares denote the charged decay mode data from the Belle Collaboration[25]. The solid circles and solid triangles denote the charged and neutral decay mode data, respectively, from the CLEO Collaboration[38]. The solid black and solid magenta lines show the best fit results for charged-and neutral-pion final states.…”