Abstract
Recent results on studies of bottomonium and bottomonium-like states at Belle are reported. The results are obtained with a 121.4 fb −1 data sample collected with the Belle detector in the vicinity of the ϒ(5 S ) resonance at the KEKB asymmetric-energy e + e − collider.
Highlights
Bottomonium is the bound system of bbquarks and is considered to be an excellent laboratory to study Quantum Chromodynamics (QCD) at low energies
Due to relatively large mass of the b quark, the system is essentially non-relativistic, the quark-antiquark QCD potential can be investigated via the bbspectroscopy
Hyperfine splitting is the difference between the spin-weighted average mass of the P-wave triplet states χbJ(nP) (n3PJ state) and that of the corresponding hb(mP), or m1P1
Summary
Bottomonium is the bound system of bbquarks and is considered to be an excellent laboratory to study Quantum Chromodynamics (QCD) at low energies. The CLEO Collaboration has recently measured the cross section of the e+e− → hc(1P)π+π− process to be comparable to that of the e+e− → J/ψπ+π− in data taken above open charm threshold [2] Such a strong enhancement in the rate contradicts to expectations as the production of the hc(1P) requires a c-quark spin flip, while production of the J/ψ does not. The Belle Collaboration reported anomalously high rates for e+e− → Υ(nS )π+π− (n = 1, 2, 3) process at energies near the Υ(5S ) mass [3]. Combined, these observations motivated a more detailed study of bottomonium production at the c.m. energy near the peak of Υ(5S ) resonance.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
