Measurement of e+e- →k+K- cross section at s =2.00 - 3.08 GeV


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Ablikim M., Achasov M., Ahmed S., Albrecht M., Alekseev M., Amoroso A., ...Daha Fazla

Physical Review D, cilt.99, sa.3, 2019 (SCI-Expanded, Scopus) identifier identifier

Özet

© 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP 3 . The cross section of the process e+e-→K+K- is measured at a number of center-of-mass energies s from 2.00 to 3.08 GeV with the BESIII detector at the Beijing Electron Positron Collider (BEPCII). The results provide the best precision achieved so far. A resonant structure around 2.2 GeV is observed in the cross section line shape. A Breit-Wigner fit yields a mass of M=2239.2±7.1±11.3 MeV/c2 and a width of Γ=139.8±12.3±20.6 MeV, where the first uncertainties are statistical and the second ones are systematic. In addition, the timelike electromagnetic form factor of the kaon is determined at the individual center-of-mass energy points.