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Register a new userExtended calculations of energy levels, radiative properties, $A_{J}$, $B_{J}$ hyperfine interaction constants, and Lande $g_{J}$-factors for nitrogen-like mbox{Ge XXVI}
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Employing two state-of-the-art methods, multiconfiguration Dirac--Hartree--Fock and second-order many-body perturbation theory, highly accurate calculations are performed for the lowest 272 fine-structure levels arising from the $2s^{2} 2p^{3}$, $2s 2p^{4}$, $2p^{5}$, $2s^{2} 2p^{2} 3l$~($l=s,p,d$), $2s 2p^{3}3l$ ($l=s,p,d$), and $2p^{4} 3l$ ($l=s,p,d$) configurations in nitrogen-like Ge XXVI. Complete and consistent atomic data, including excitation energies, lifetimes, wavelengths, hyperfine structures, Lande $g_{J}$-factors, and E1, E2, M1, M2 line strengths, oscillator strengths, and transition rates among these 272 levels are provided. Comparisons are made between the present two data sets, as well as with other available experimental and theoretical values. The present data are accurate enough for identification and deblending of emission lines involving the $n=3$ levels, and are also useful for modeling and diagnosing fusion plasmas.
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Using the multiconfiguration Dirac-Hartree-Fock and the relativistic configuration interaction methods, a consistent set of transition energies and radiative transition data for the main states of the $2s^2 2p^4$, $2s 2p^5$, $2p^6$, $2s^2 2p^3 3s$, $2s^2 2p^3 3p$, $2s^2 2p^3 3d$, $2s 2p^4 3s$, $2s 2p^4 3p$, and $2s 2p^4 3d$ configurations in O-like Ions between Ar XI ($Z = 18$) and Cr XVII ($Z = 24$) is provided. Our data set is compared with the NIST compiled values and previous calculations. The data are accurate enough for identification and deblending of new emission lines from hot astrophysical and laboratory plasmas. The amount of data of high accuracy is significantly increased for the $n = 3$ states of several O-like ions, where experimental data are very scarce.
The form factors and coupling constants of the meson vertices J/psi D_s D_s and phi D_s D_s were calculated using three point correlation functions within the QCD Sum Rules formalism. We have considered the cases where phi, D_s and J/psi mesons are off-shell obtaining, for each vertex, two different form factors and its corresponding coupling constants, namely g_{J/psi D_s D_s} = 6.20^{+0.97}_{-1.15} and g_{phi D_s D_s} = 1.85^{+0.22}_{-0.23}.
In order to make a further confirmation about the assignments of the excited bottom and bottom strange mesons $B_{1}(5721)$, $B_{2}^{*}(5747)$, $B_{s1}(5830)$, $B_{s2}^{*}(5840)$ and meanwhile identify the possible assignments of $B_{J}(5840)$, $B_{J}(5970)$, we study the strong decays of these states with the $^{3}P_{0}$ decay model. Our analysis support $B_{1}(5721)$ and $B_{2}^{*}(5747)$ to be the $1P_{1}$ and $1^{3}P_{2}$ assignments and the $B_{s1}(5830)$, $B_{s2}^{*}(5840)$ to be the strange partner of $B_{1}(5721)$ and $B_{2}^{*}(5747)$. Besides, we tentatively identify the recently observed $B_{J}(5840)$, $B_{J}(5970)$ as the $2^{3}S_{1}$ and $1^{3}D_{3}$ states, respectively. It is noticed that this conclusion needs further confirmation by measuring the decay channel to $Bpi$ of $B_{J}(5840)$ and $B_{J}(5970)$ in experiments.
In this work, we tentatively assign the charmed mesons $D_{J}(2580)$, $D_{J}^{*}(2650)$, $D_{J}(2740)$, $D_{J}^{*}(2760)$, $D_{J}(3000)$ and $D_{J}^{*}(3000)$ observed by the LHCb collaboration according to their spin-parity and masses, then study their strong decays to the ground state charmed mesons plus light pseudoscalar mesons with the $^{3}P_{0}$ model. According to these study, we assigned the $D_{J}^{*}(2760)$ as the $1Dfrac{5}{2}3^{-}$ state, the $D_{J}^{*}(3000)$ as the $1Ffrac{5}{2}2^{+}$ or $1Ffrac{7}{2}4^{+}$ state, the $D_{J}(3000)$ as the $1Ffrac{7}{2}3^{+}$ or $2Pfrac{1}{2}1^{+}$ state in the $D$ meson family. As a byproduct, we also study the strong decays of $2Pfrac{1}{2}0^{+}$,$2Pfrac{3}{2}2^{+}$, $3Sfrac{1}{2}1^{-}$, $3Sfrac{1}{2}0^{-}$ etc, states, which will be helpful to further experimentally study mixings of these $D$ mesons.
We have performed the first $n_f = 2+1+1$ lattice QCD computations of the properties (masses and decay constants) of ground-state charmonium mesons. Our calculation uses the HISQ action to generate quark-line connected two-point correlation functions on MILC gluon field configurations that include $u/d$ quark masses going down to the physical point, tuning the $c$ quark mass from $M_{J/psi}$ and including the effect of the $c$ quarks electric charge through quenched QED. We obtain $M_{J/psi}-M_{eta_c}$ (connected) = 120.3(1.1) MeV and interpret the difference with experiment as the impact on $M_{eta_c}$ of its decay to gluons, missing from the lattice calculation. This allows us to determine $Delta M_{eta_c}^{mathrm{annihiln}}$ =+7.3(1.2) MeV, giving its value for the first time. Our result of $f_{J/psi}=$ 0.4104(17) GeV, gives $Gamma(J/psi rightarrow e^+e^-)$=5.637(49) keV, in agreement with, but now more accurate than experiment. At the same time we have improved the determination of the $c$ quark mass, including the impact of quenched QED to give $overline{m}_c(3,mathrm{GeV})$ = 0.9841(51) GeV. We have also used the time-moments of the vector charmonium current-current correlators to improve the lattice QCD result for the $c$ quark HVP contribution to the anomalous magnetic moment of the muon. We obtain $a_{mu}^c = 14.638(47) times 10^{-10}$, which is 2.5$sigma$ higher than the value derived using moments extracted from some sets of experimental data on $R(e^+e^- rightarrow mathrm{hadrons})$. This value for $a_{mu}^c$ includes our determination of the effect of QED on this quantity, $delta a_{mu}^c = 0.0313(28) times 10^{-10}$.
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