arXiv subjects
Publications and source records attributed to L. Burakovsky.
We show that only additivity of inverse Regge slopes is consistent with both the formal chiral limit m(n)\to 0 and the heavy quark limit M(Q)>>M(n), where n=u,d, and m,M are current and constituent quark masses, respectively.
We prove the validity of Schwinger's quartic nonet mass formula for a general nonet structure with the isoscalar singlet mass being shifted from its ``ideal'' value. We apply this formula to the problem of the correct q\bar{q} assignment for the scalar meson nonet. The results favor scalar isoscalar singlet and isoscalar octet masses in the vicinity of 1 GeV and 1.45 GeV, respectively. We explain the failure of Schwinger's formula for the pseudoscalar meson nonet, and suggest a new version of this formula, modified by the inclusion of the pseudoscalar decay constants, which holds with improved accuracy for this nonet. We also rederive the new Gell-Mann-Okubo mass formula 3M^2(n\bar{n},I=1)+2M^2(s\bar{s})=4M^2(s\bar{n})+M^2(n\bar{n},I=0) (n=u,d), suggested in our previous publications.
We rederive the new SU(3) multiplet mass formula 2M^2(s\bar{s})+3M^2(n\bar{n}, I=1)=4M^2(s\bar{n})+M^2(n\bar{n},I=0) (n=u,d}, obtained in our previous paper by using Regge phenomenology, for the pseudoscalar and scalar mesons in the Nambu-Jona-Lasinio model with instanton-induced interaction. We apply this formula to the problem of the correct q\bar{q} assignment for the scalar meson nonet. Our results strongly favor the masses of the scalar isoscalar mostly octet and mostly singlet states in the vicinity of 1.45 GeV and 1.1 GeV, respectively
We show that the application of Regge phenomenology to SU(4) meson multiplets leads to a new Gell-Mann-Okubo mass-mixing formula in the SU(3) sector, 3m_1^2 + (cos theta)^2 m_0^2 + (sin theta)^2 m_{0'}^2 + sqrt{2} sin(2theta) (m_0^2 - m_{0'}^2) = 4m_{1/2}^2, where m_1,m_{1/2},m_0,m_{0'} are the masses of the isovector, isodoublet, isoscalar mostly octet and isoscalar mostly singlet states, respectively, and theta is the nonet mixing angle. For an ideally mixed nonet, theta = arctan(1/sqrt{2}), this formula reduces to 2m_0^2 + 3m_1^2 = 4m_{1/2}^2 + m_{0'}^2 which holds with an accuracy of ~1% for vector and tensor mesons. For pseudoscalar mesons, with the eta-eta' mixing angle -arctan[1/(2sqrt{2})] ~ -19.5^o, in agreement with experiment, it leads to the relation 4m_K^2 = 3m_pi^2 + m_{eta'}^2 which holds to an accuracy of better than 1% for the measured pseudoscalar meson masses.
By assuming the existence of (quasi)-linear Regge trajectories for heavy mesons, we derive new quadratic mass relations of non-Gell-Mann-Okubo type, 6M^2(q-qbar)+3M^2(c-cbar)=8M^2(c-qbar), 20M^2(q-qbar)+5M^2(b-bbar)= 16M^2(b-qbar), q=n(=u,d),s, which show excellent agreement with experiment. We also establish the sum rule M^2(i-ibar)+M^2(j-jbar)-2M^2(j-ibar)\approx const for any pair of flavors, (i,j).
By assuming the existence of (quasi)-linear baryon Regge trajectories, we derive new quadratic Gell-Mann-Okubo type baryon mass relations. These relations are used to predict the masses of the charmed baryons absent from the Baryon Summary Table so far, in good agreement with the predictions of many other approaches.
The mass spectrum of P-wave mesons is considered in a nonrelativistic constituent quark model. The results show the common mass degeneracy of the isovector and isodoublet states of the scalar and tensor meson nonets, and do not exclude the possibility of a similar degeneracy of the same states of the axial-vector and pseudovector nonets. Current experimental hadronic and τ-decay data suggest, however, a different scenario leading to the a_1 meson mass \simeq 1190 MeV and the K_{1A}-K_{1B} mixing angle \simeq (37\pm 3)^o. Possible s\bar{s} states of the four nonets are also discussed.
By assuming the existence of (quasi)-linear Regge trajectories for 25-plet mesons in the low energy region, we derive a new, 14th power, meson mass relation. This relation may be reduced to a quadratic Gell-Mann-Okubo type formula by fitting the values of the Regge slopes of these (quasi)-linear trajectories. Such a formula holds with an accuracy of ~2% for vector mesons, and also suggests that the quantum number I(J^P)=1/2(2^{+}) should be assigned to the both B_J(5732) and B_{sJ}(5850) mesons discovered recently. We also discuss reasons for the failure of group theory to produce correct mass relations for heavy quarkonia.
By assuming the existence of (quasi)-linear Regge trajectories for heavy quarkonia in the low energy region, we derive a new, sixth power, meson mass relation which shows good agreement with experiment for both charmed and beauty mesons. This relation may be reduced to a quadratic Gell-Mann-Okubo type formula by fitting the values of the Regge slopes of these (quasi)-linear trajectories. For charmed mesons, such a formula holds with an accuracy of $\sim 1$%, and is in qualitative agreement with the relation obtained previously by the application of the linear spectrum to a meson hexadecuplet.
By the application of a linear mass spectrum to a composite system of both the pseudoscalar and scalar meson nonets, we find three mass relations for the masses of the scalar states which suggest the $q\bar{q}$ assignment for the scalar meson nonet: $a_0(1320),$ $K_0^\ast (1430),$ $f_0(1500),$ $f_0'(980).$
In a nonrelativistic constituent quark model we find a constraint on the mixing angle of the strange axial-vector mesons, $35^o\stackrel{<}{\sim } θ_K\stackrel{<}{\sim }55^o,$ determined solely by two parameters: the mass difference of the $a_1$ and $b_1$ mesons and the ratio of the constituent quark masses.
The mass spectrum of D-wave mesons is considered in a nonrelativistic constituent quark model. The results show a common mass degeneracy of the isovector and isodoublet states of the 1 $^3D_1$ and 1 $^3D_3$ nonets, and suggest therefore that the $K^\ast (1680)$ cannot be the I=1/2 member of the 1 $^3D_1$ nonet. They also suggest that the $η_2(1870),$ presently omitted form the Meson Summary Table, should be interpreted as the I=0 $s\bar{s}$ state of the 1 $^1D_2$ nonet.
The formulas for the temperature dependences of the non-strange and strange quark condensates are derived by taking into account the contribution of the massive resonances. Critical temperature of the chiral symmetry restoration transition is established to be 190 MeV if only meson resonances are considered, and 175 MeV if both meson and baryon resonances are taken into account.
It is argued that the mass spectrum of a meson nonet is linear, consistent with the standard Gell-Mann--Okubo mass formula and leading to an extra Gell-Mann--Okubo mass relation for the masses of the isoscalar states. This relation is shown to hold with an accuracy of up to $\sim $3\% for all well-established nonets. It also suggests a new $q\bar{q}$ assignment for the scalar meson nonet.
It is argued that the mass spectrum of a baryon octet is linear, consistent with a Gell-Mann--Okubo type relation for the squared masses of the baryons obtained previously by Balázs and Nicolescu. The mass spectrum of a baryon decuplet is briefly discussed.
Using a linear mass spectrum of an $SU(4)$ meson hexadecuplet, we derive the Gell-Mann--Okubo mass formula for the charmed mesons, in good agreement with experiment. Possible generalization of this method to a higher symmetry group is briefly discussed.
In the model of a first order quark-gluon/hadron phase transition in which the hadronic phase is considered as vacuum bubbles growing in the quark-gluon background with chiral symmetry broken inside the bubble, we find the estimate for the length scale associated with inhomogeneities originated during the transition, $10$ m $\;\stackrel{<}{\sim }\ell \stackrel{<}{\sim }40$ m, being sufficient to produce significant effects on cosmological nucleosynthesis.
The equation of state of hot hadronic matter is obtained, by taking into account the contribution of the massive states with the help of the resonance spectrum $τ(m)\sim m^3$ justified by the authors in previous papers. This equation of state is in agreement with that provided by the low-temperature expansion for the pion intracting gas. It is shown that in this picture the deconfinement phase transition is absent, in agreement with lattice gauge calculations which show the only phase transition of chiral symmetry restoration. The latter is modelled with the help of the restriction of the number of the effective degrees of freedom in the hadron phase to that of the microscopic degrees of freedom in the quark-gluon phase, through the corresponding truncation of the hadronic resonance spectrum, and the decrease of the effective hadron masses with temperature, predicted by Brown and Rho. The results are in agreement with lattice gauge data and show a smooth crossover in the thermodynamic variables in a temperature range $\sim 50$ MeV.