Hyperfine splitting and decay of heavy mesons

Regge trajectories in the framework of the relativistic action-at-a-distance theory

“…But the slope coefficient k (v) ≈ 9.896 together with the string tension value a = 0.18 GeV 2 yield an overestimated slope of the Regge trajectories: σ = k (v) a = 1.78 GeV 2 > 1.15 GeV 2 . A plausible reason of this disagreement in that the purely vector nature of the interaction in the model does not meet the actual relativistic structure of the confinement interaction which is commonly attributed to the scalar [2,15,32] or scalar-vector [4,[25][26][27][28][29] type.…”

“…Mass spectra of heavy mesons (contaning c and b quarks) are described well by means of potential models with the static Cornell potential [1][2][3][4][5][6] U (r) = −α/r + ar .…”

“…In particular, α = 4 3 α s where the running strong coupling constant α s grows from 0.2 − 0.25 for heavy quarks to 0.6 − 0.8 for light ones [2]. The string tension parameter a is frequently used as an adjustable parameter from the range a = 0.15÷0.3 GeV 2 [1][2][3][4][5][6]. However, in contrast to α, the parameter a is considered as a universal one, i.e.…”

“…Spin effects are taken into account by means of relativistic corrections to the static potential [1][2][3][4][5][6]. They must be attributed to the scalar or vector type, in accordance with a relativistic field-theoretical nature of the interaction.…”

“…The nature of the linear term is less clear; it is specified as a scalar interaction or scalar-vector admixture. The rate ξ of, say, a vector component in the long-range interaction can be used as an adjustable parameter [1][2][3][4][5]. The value of ξ is not well conditioned as yet, since it strongly depends on the data precision and a theoretical interpretation of fine splitting effects.…”