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Comment on "Calculation of Quarkonium Spectrum and $m_{b}, m_{c}$ to Order $\alpha^{4}_{s}$"

In a recent paper, we included two loop, relativistic one loop and second order relativistic tree level corrections, plus leading nonperturbative contributions, to obtain a calculation of the lower states in the heavy quarkonium spectrum correct up to, and including, $O(\alpha_s^4)$ and leading valu...

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Detalles Bibliográficos
Autores principales: Pineda, A., Yndurain, F.J.
Lenguaje:eng
Publicado: 1998
Materias:
Acceso en línea:https://dx.doi.org/10.1103/PhysRevD.61.077505
http://cds.cern.ch/record/374473
Descripción
Sumario:In a recent paper, we included two loop, relativistic one loop and second order relativistic tree level corrections, plus leading nonperturbative contributions, to obtain a calculation of the lower states in the heavy quarkonium spectrum correct up to, and including, $O(\alpha_s^4)$ and leading value of the two loop static coefficient due to Peter; this been recently challenged by Schr der. In our previous paper we used Peter's result; in the present one we now give results with Schröder's, as this is likely to be the correct one. The variation is slight as the value of $b_1$ is only one among the various $O(\alpha_s^4)$ contributions. With Schr der's expression we now have, $m_b=5\,001^{+104}_{-66}\;\mev;\quad \bar{m}_b(\bar{m}_b^2)=4\,440^{+43}_{-28}\;\mev, $m_c=1\,866^{+190}_{-154}\;\mev;\quad \bar{m}_c(\bar{m}_c^2)=1\,531^{+132}_{-127}\;\mev. Moreover, $\Gammav(\Upsilonv\rightarrow e^+e^-)=1.07\pm0.28\;\kev \;(\hbox{exp.}=1.320\pm0.04\,\kev)$ and the hyperfine splitting is predicted to be $M(\Upsilonv)-M(\eta)=47^{+15}_{-13}\;\mev.$