1-7 Hadronic Loop Effect to r(5S)→xbJw Decays

Very recently, Belle announced their observation of Υ(5S) ! bJ! (J = 0;1; 2), indicating that the Υ(5S) ! bJ! decays also have large decay widths, i.e., the measured branch ratios of Υ(5S) ! bJ! are < 3:410??3,(1:640:23+0:30??0:22)10??3, and (0:570:220:07)10??3 with J =0;1; 2, respectively[1]. It should be noticed that eventhough the tree level contributions to Υ(5S)! bJ! (J =0;1;2) should be strongly suppressed due to the Okubo-Zweig-Iizuka (OZI) rule, such large decay widths are observed, which again inspires our interest in understandingsuch quantities. In this work, we propose that the contribution from the hadronic loop should be considered instudying Υ(5S)! bJ!.