@Article{BABARCollaborationLees_etal2011, author="BABAR Collaboration (Lees, J. P. et al and Martinez-Vidal, F. and Oyanguren, A.", title="Study of Y(3S, 2S) -> eta Y(1S) and Y(3S, 2S) -> pi(+) pi(-) Y(1S) hadronic transitions", journal="Physical Review D", year="2011", publisher="Amer Physical Soc", volume="84", number="9", pages="092003--8pp", abstract="We study the Y(3S, 2S) -> eta Y(1S) and Y (3S,2S) -> pi(+)pi(-) transitions with 122 x 10(6) x Y(3S) and 100 x 10(6) Y (2S) mesons collected by the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider. We measure B[Y(2S) -> eta Y(1S)] = (2.39 +/- 0.31 (stat) +/- 0.14(syst)) x 10(-4) and Gamma[Y(2S) -> eta Y(1S)]/Gamma[Y(2S) ->pi(+)pi(-)(1S)] -- (2.39 +/- 0.31(stat) +/- 0.14(syst)) x 10(-3). We find no evidence for Y(3S) -> eta Y (1S) and obtain B[Y(3S) -> eta Y(1S)] < 1.0 x 10(-4) and Gamma[Y (3S) -> eta Y(1S)/Gamma[Y(3S) -> pi(+)pi(-) Y(1S)] < 2.3 x 10(-3) as upper limits at the 90{\%} confidence level. We also provide improved measurements of the Y(S) -- Y(1S) and Y(3S) -- Y (1S) mass differences, 562.170 +/- 0.007(stat) +/- 0.088(syst). MeV/c(2) and 893.813 +/- 0: 015(stat) +/- 0.107(syst.) MeV/c(2), respectively.", optnote="WOS:000296890600003", optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=819), last updated on Mon, 19 Dec 2011 13:56:34 +0000", issn="1550-7998", doi="10.1103/PhysRevD.84.092003", opturl="http://arxiv.org/abs/1108.5874", opturl="https://doi.org/10.1103/PhysRevD.84.092003", archivePrefix="arXiv", eprint="1108.5874", language="English" }