We investigate the semileptonic hyperon decays within the framework of the self-consistent SU(3) chiral quark-soliton model ($χ$QSM). We take linear $1/N_c$ rotational as well as linear $m_s$ corrections into account and apply the symmetry conserving quantization. We present the results for the form factors $f_1(Q^2)$, $f_2(Q^2)$ and $g_1(Q^2)$ in addition to the semileptonic decay constants of hyperons. We also have calculated the radii and dipole masses of these form factors for all relevant strangeness-conserving and strangeness-changing transitions.
This note emphasizes that due to isospin violation the two central states in the octet mix, and this mixing can be measured in semileptonic decays, in particular with an accurate determination of the sigma plus semileptonic branching ratio.
We perform a new numerical analysis of hyperon semileptonic decays emphasizing the systematic uncertainties. The poor understanding of SU(3) symmetry breaking effects at second order in the vector form factor translates into a large error of |V(us)|. Using our determination |V(us)| = 0.226 +/- 0.005 together with those coming from other sources we test the unitarity of the CKM matrix.
We obtain a model-independent expression for the complete Dalitz plot of semileptonic decays of polarized hyperons, which includes both the three-body and the four-body regions. We calculate radiative corrections to order alpha, neglecting terms of order alpha q/(pi M_1), where q is the four-momentum transfer and M_1 is the mass of the decaying hyperon. Our results exhibit explicitly the correlation between the emitted hyperon three-momentum and the spin of the decaying hyperon. This allows us to obtain the corresponding radiative corrections to the integrated emitted hyperon spin-asymmetry co…
We compute the rates of semileptonic B_A \to B_Bl^-l^- (l=e or μ) hyperon transitions in a model where intermediate states involve loops of baryons and a Majorana neutrino. These rates turn out to be well below present experimental bounds and other theoretical estimates. From the experimental upper limit on the Ξ^- \to pμ^-μ^- decay, we derive the bound <m_{μμ}> < 22 TeV for the effective Majorana mass of the muon neutrino. Also, an estimate of background contributions for these decays due to the allowed B_A \to B_Bl^-l^-\barν\barν decays are provided.
A model-independent determination of the CKM matrix element V_{us} from five measured strangeness-changing hyperon semileptonic decays is performed. Flavor SU(3) symmetry breaking effects in the leading vector and axial-vector form factors are analyzed in the framework of the 1/N_c expansion of QCD. A fit to experimental data allows one to extract the value V_{us}=0.2199\pm 0.0026, which is comparable to the one from K_{e3} decays. This reconciliation is achieved through second-order symmetry breaking effects of a few percent in the form factors f_1, which increase their magnitudes over their …
We obtain a model-independent expression for the Dalitz plot of semileptonic decays of polarized hyperons including radiative corrections to order alpha and neglecting terms of order (alpha q)/(pi M_1), where q is the four-momentum transfer and M_1 is the mass of the decaying hyperon. We specialize our results to exhibit the correlation between the charged-lepton momentum and the spin of the decaying hyperon. We present results for the three-body region of the Dalitz plot and for the complete Dalitz plot (which includes the four-body region). From these results we also obtain the corresponding…
Very accurate analytical expressions for the radiative corrections of unpolarized hyperons semileptonic decays of charged and neutral baryons have been obtained in the recent past. Some of these formulas contain logarithmic singularities at the edges of the Dalitz plot for the three- and four-body decays. These singularities are analyzed and integrated analytically to obtain new divergentless formulas for the energy spectrum of the produced beta particle. The new equations contain terms of the order alpha times the momentum transfer, are applicable to any beta decay process and are suitable fo…
We study the success to describe hyperon semileptonic decays of four models that incorporate second-order SU(3) symmetry breaking corrections. The criteria to assess their success is by determining V_{us} in each of the three relevant hyperon semileptonic decays and comparing the values obtained with one another and also with the one that comes from K_{l3} decays. A strong dependence on the particular symmetry breaking model is observed. Values of V_{us} which do not agree with the one of K_{l3} are generally obtained. However, in the context of chiral perturbation theory, only the model whose…
By considering that the weak currents and the electromagnetic current are members of the same SU(3) octet, two sum rules involving leading vector form factors in hyperon semileptonic decays are derived in the limit of exact flavor SU(3) symmetry. Deviations from this limit arise from second-order SU(3) symmetry-breaking effects, according to the Ademollo-Gatto theorem. The 1/N_c expansion of QCD is used to evaluate such effects. One sum rule vanishes identically even in the presence of symmetry breaking and the other one obtains contributions mainly from the 10+\overline{10} representation. Re…
We investigate the hyperon semileptonic decays and the quark spin content of the proton $ΔΣ$ taking into account flavor SU(3) symmetry breaking. Symmetry breaking is implemented with the help of the chiral quark-soliton model in an approach, in which the dynamical parameters are fixed by the experimental data for six hyperon semileptonic decay constants. As a result we predict the unmeasured decay constants, particularly for $Ξ^0 \to Σ^+$, which will be soon measured and examine the effect of the SU(3) symmetry breaking on the spin content $ΔΣ$ of the proton. Unfortunately large experimental e…
Flavor SU(3) symmetry breaking in the hyperon semileptonic decay form-factors is analyzed using the 1/N expansion. A detailed comparison with experimental data shows that corrections to f_1 are approximately 10%, which agrees with theoretical expectations. Corrections to g_1 are compatible with first-order symmetry breaking. A fit to the experimental data allows one to predict the g_1 form factor for Xi^0 -> Sigma^+ decay. The proton matrix element of the T^8 component of the axial current (which is equal to 3F-D in the SU(3) symmetry limit) is found to be approximately 0.34.
Existing analyzes of baryon semileptonic decays indicate the presence of a small SU(3) symmetry breaking in hyperon semileptonic decays, but to provide evidence for SU(3) symmetry breaking, one would need a relation similar to the Gell-Mann Okubo(GMO) baryon mass formula which is satisfied to a few percents, showing evidence for SU(3) symmetry breaking in the divergence of the vector current matrix element. In this paper, we shall present a similar GMO relation for the hyperon semileptonic decay axial vector form factors. Using these relations and the measured axial vector current to vector cu…
Using the exisiting experimental data for hyperon semileptonic decays and the flavor-singlet axial-vector charge $g_{A}^{(0)}$ from polarized deep inelastic scattering of the proton, we derive the decay width of the $Θ^{+}$ pentaquark baryon. We take into account the effects of flavor SU(3) symmetry breaking within the framework of the chiral quark-soliton model. All dynamical parameters of the model are fixed by using the five experimental hyperon semileptonic decay constants and flavor singlet axial-vector charge. We obtain the numerical results of the decay width of the $Θ^{+}$ pentaquark b…
Existing analyzes of baryon semileptonic decays indicate the presence of a small SU(3) symmetry breaking in hyperon semileptonic decays, but to provide evidence for SU(3) symmetry breaking, one would need a relation similar to the Gell-Mann--Okubo (GMO) baryon mass formula which is satisfied to a few percents, showing evidence for a small SU(3) symmetry breaking effect in the GMO mass formula. In this talk, I would like to present a similar GMO relation obtained in a recent work for hyperon semileptonic decay axial vector current matrix elements. Using these generalized GMO relations for the m…
Using a technique that is not subject to first-order SU(3) symmetry breaking effects, we determine the $V_{us}$ element of the CKM matrix from data on semileptonic hyperon decays. We obtain $V_{us}$ =0.2250(27). This value is of similar precision to the one derived from $K_{l3}$, but higher and in better agreement with the unitarity requirement, $|V_{ud}|^2+|V_{us}|^2+|V_{ub}|^2=1$.
We present preliminary results of an exploratory lattice study of the vector form factor $f_1(q^2 = 0)$ relevant for the semileptonic hyperon decay $Σ^{-} --> n l ν$. This study is based on the same method used for the extraction of $f^+(0)$ for the decay $K^0 --> π^{-} l ν$. The main purpose of this study is to test the method for hyperon form factors in order to estimate the precision that can be reached and the importance of SU(3)-breaking effects.
I shall present a pedagogical discussion of hyperon semileptonic decays, covering some of the historical background, the basics notions of hyperon semileptonic decays, deeply inelastic scattering and the CKM matrix, and the description of SU(2) and SU(3) breaking. I shall also present a prediction for a process under current experimental study.
Data for magnetic moments and semileptonic decays show disagreements between experimental values and theoretical predictions not easily explained by simple models for $Λ$ and $Σ$ hyperons.
We investigate the hyperon semileptonic decay constants, $f_2/f_1$, and $g_1/f_1$, within a general framework of a chiral soliton model. All relevant parameters for the SU(3) baryon wave functions were unambiguously determined by using the experimental data for the masses of the baryon octet and the decuplet. Using then the existing experimental data for the magnetic moments of the baryon octet and the decay constants of hyperon semileptonic decays, we are able to determine all the hyperon semileptonic decay constants $f_2/f_1$ and $g_1/f_1$ of the baryon octet unequivocally. In addition, we a…
A detailed calculation of electric and magnetic static polarizabilities of octet hyperons is presented in the framework of the bound state soliton model. Both seagull and dispersive contributions are considered, and the results are compared with different model predictions.
The octet-baryon axial-vector charges and the g1/f1 ratios measured in the semileptonic hyperon decays are studied up to O(p^3) using the covariant baryon chiral perturbation theory with explicit decuplet contributions. We clarify the role of different low-energy constants and find a good convergence for the chiral expansion of the axial-vector charges of the baryon octet, g1(0), with O(p^3) corrections typically around 20% of the leading ones. This is a consequence of strong cancellations between different next-to-leading order terms. We show that considering only non-analytic terms is not en…
We analyze the numerical determination of the quark mixing factor V(us) from hyperon semileptonic decays. The discrepancies between the results obtained in two previous studies are clarified. Our fits indicate sizeable SU(3) breaking corrections, which unfortunately can only be fully determined from the data at the first order. The lack of a reliable theoretical calculation of second-order symmetry breaking effects translates into a large systematic uncertainty, which has not been taken into account previously. Our final result, V(us) = 0.226 +/- 0.005, is not competitive with the existing det…
The radiative decays of hyperons are studied in the framework of the bound state soliton model. Detailed predictions for the total decay widths and the E2/M1 ratios corresponding to decuplet--to--octet electromagnetic transitions are presented in relation to future planned experiments at CEBAF and Fermilab. The results are compared to those obtained in quark based models.
We derive the anharmonic correction to the hyperon energy in the bound state version of the topological soliton model for the hyperons, and show that it represents a negative correction of at most 10% to the energy of the bound heavy flavour two-meson system in the case of cascade hyperons. The main anharmonic correction arises from the mass term in the Lagrangian density. For large meson masses the consistency of the model requires that the anharmonic correction decreases as the inverse square root of the mass of the heavy flavour meson.
We show that the predicted hyperon masses in the topological soliton model are very sensitive to the value of the gluon condensate parameter that appears when the scale invariance and trace anomaly of QCD are taken into account by introduction of a dilaton field. This contrasts with the insensitivity of the soliton properties to the dilaton coupling. In order that the predicted strange and charmed hyperon spectra agree with the empirical ones the gluon condensate parameter has to be about (400 MeV)$^4$, which agrees with the result obtained from QCD sum rules. This implies that the bag formed …
We investigate the discovery potential of semileptonic hyperon decays in terms of searches of new physics at teraelectronvolt scales. These decays are controlled by a small $SU(3)$-flavor breaking parameter that allows for systematic expansions and accurate predictions in terms of a reduced dependence on hadronic form factors. We find that muonic modes are very sensitive to non-standard scalar and tensor contributions and demonstrate that these could provide a powerful synergy with direct searches of new physics at the LHC.
According to the large $N_C$ limit of QCD baryons are considered as soliton solutions in effective mesons theories. While the classical solitons dwell in the isospin subgroup of flavor SU(3) hyperon states are generated by canonical quantization of the collective coordinates which describe the flavor orientation of the soliton. The resulting Hamiltonian is diagonalized exactly allowing one to discuss the dependence of various baryon properties on flavor symmetry breaking. In particular axial charges, baryon magnetic moments and radiative decay widths are considered.
The paper describes the quantization of the SU(3) smibosonized Nambu-Jona-Lasinio model and results for mass splittings, including isospin splittings, and axial couplings. The agreement with the data is surprisingly good.
We review a novel model-independent approach to the analysis of new-physics effects in the $s\to u\ell^-\barν$ transitions. We apply it to (semi)leptonic kaon decays and study their complementarity with pion and hyperon $β$ decays or with collider searches of new physics.
We review the status of hyperon semileptonic decays. The central issue is the $V_{us}$ element of the CKM matrix, where we obtain $V_{us}=0.2250 (27)$. This value is of similar precision, but higher, than the one derived from $K_{l3}$, and in better agreement with the unitarity requirement, $|V_{ud}|^2+|V_{us}|^2+|V_{ub}|^2=1$. We find that the Cabibbo model gives an excellent fit of the existing form factor data on baryon beta decays ($χ^{2} = 2.96$ for 3 degrees of freedom) with $F + D = 1.2670 \pm 0.0030$, $F - D = -0.341 \pm 0.016$, and no indication of flavour-SU(3)-breaking effects. We i…
Electroweak Transitions of Hyperons and Charmed Baryons: Opportunities and Prospects
Uppsala University（乌普萨拉大学）；National Centre for Nuclear Research（国家核研究中心）；University of Cyprus（塞浦路斯大学）；The Cyprus Institute（塞浦路斯研究所）；Institute of High Energy Physics（高能物理研究所）；Lund University（隆德大学）；École Polytechnique Fédérale de Lausanne（洛桑联邦理工学院）；University of Graz（格拉茨大学）
We study the parity violating hyperon non-leptonic weak decays in the three flavor Skyrme model. We follow the approach in which the symmetry breaking terms in the action are diagonalized exactly within the collective coordinate approximation. We show that although this method introduces some configuration mixing, the $ΔI =1/2$ rule is numerically well satisfied. In addition, and in contrast to previous calculations, we show that not only the relative amplitudes are in good agreement with the empirical values but also their absolute values. The issue of whether the strong interaction enhanceme…
Using the known experimental data for the hyperon semileptonic decay constants, we calculate integrated quark densities $Δq_Λ$ and $% ΔΣ_Λ$ for the hyperon $Λ$ with flavor SU(3) symmetry breaking taken into account. Symmetry breaking is implemented with the help of the chiral quark-soliton model in an approach, in which the dynamical parameters are fixed by the experimental data for six hyperon semileptonic decay constants. This parametrization allows us to reproduce the first moment of the $g_1^{\rm p}(x)$ of the proton. For the $Λ$ we obtain: $Δu_Λ=Δd_Λ \approx 0$ and $Δs_Λ$ of the order of …
In the chirally symmetric Nambu--Jona-Lasinio model baryons are described as chiral solitons of mesonic quark--antiquark bound states. Hyperons are investigated in two complementary pictures: the bound state approach of Callan and Klebanov and the collective approach of Yabu and Ando. The latter is used to compute the strange vector form factors of the nucleon providing estimates for the strange electric mean square radius and the strange magnetic moment of the nucleon.
Using the helicity method we derive complete formulas for the joint angular decay distributions occurring in semileptonic hyperon decays including lepton mass and polarization effects. Compared to the traditional covariant calculation the helicity method allows one to organize the calculation of the angular decay distributions in a very compact and efficient way. In the helicity method the angular analysis is of cascade type, i.e. each decay in the decay chain is analyzed in the respective rest system of that particle. Such an approach is ideally suited as input for a Monte Carlo event generat…
We calculate the semileptonic baryon octet-octet transition form factors using a manifestly Lorentz covariant quark model approach based on the factorization of the contribution of valence quarks and chiral effects. We perform a detailed analysis of SU(3) breaking corrections to the hyperon semileptonic decay form factors. We present complete results on decay rates and asymmetry parameters including lepton mass effects for the rates.
A relativistic constituent quark model is used to calculate the semileptonic beta decay of nucleons and hyperons. The parameters of the model, namely, the constituent quark mass and the confinement scale, are fixed by a previous calculation of the magnetic moments of the baryon octet within the same model. We discuss the momentum dependence of the form factors, possible configuration mixing and SU(3) symmetry breaking. We conclude that the relativistic constituent quark model is a good framework to analyze electroweak properties of the baryons.
The semileptonic decays and two-body nonleptonic decays of light baryon octet ($T_8$) and decuplet ($T_{10}$) consisting of light $u,d,s$ quarks are studied with the SU(3) flavor symmetry in this work. We obtain the amplitude relations between different decay modes by the SU(3) irreducible representation approach, and then predict relevant branching ratios by present experimental data within $1 σ$ error. We find that the predictions for all branching ratios except $\mathcal{B}(Ξ\rightarrow Λ^0π)$ and $\mathcal{B}(Ξ^*\rightarrow Ξπ)$ are in good agreement with present experimental data, that im…
Decays of heavy mesons and of heavy hyperons are used to provide tests of the standard model and information about new mixing schemes for the $η$ and $η^{'}$ mesons. These include the two body decays $B_s \to J / ψM$ and $B_d \to J / ψM$, $B \to η(η^{'})K(K^\ast)$ and $Λ_b \to Λη(η^{'})$, semileptonic $D$ decays, and properties of radially excited mesons.
We discuss the result of a recent quenched lattice calculation of the K -> pi vector form factor at zero-momentum transfer, relevant for the determination of |V_us| from K-> pi l nu decays. Using suitable double ratios of three-point correlation functions, we show that it is possible to calculate this quantity at the percent-level precision. The leading quenched effects are corrected for by means of quenched chiral perturbation theory. The final result, f+(0) = 0.960 +- 0.005_stat +- 0.007_syst, turns out to be in good agreement with the old quark model estimate made by Leutwyler and Roos. In …
Unified study of hyperon semileptonic decays in a relativistic three-quark model
University of Chinese Academy of Sciences（中国科学院大学）；Ningbo University（宁波大学）；Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）；Tsinghua University（清华大学）
We develop the formalism to study the hyperon-nucleon interaction potential within the bound state approach to the SU(3) Skyrme model. The general framework is illustrated by applying it to the diagonal $ΛN$ potential. The central, spin-spin and tensor components of this interaction are obtained and compared with those derived using alternative schemes.
We investigate the potential of rare hyperon decays to probe the short distance structure in the $s\to dν\barν$ and $s\to d\ell^+\ell^-$ transitions. Hyperon decays into neutrinos ($B_1\to B_2ν\barν$) can be reliably predicted by using form factors determined in baryon chiral perturbation theory. Their decay rates are sensitive to different short-distance operators, as compared to their kaon counterparts, and the corresponding branching fractions are in the range of $10^{-14}\sim10^{-13}$ in the standard model. In the context of the low-energy effective theory, we find that the anticipated BES…
The dependence of inclusive weak decay rates of heavy hadrons on the flavors of spectator light quarks is revisited with application to decays of charmed and b hyperons. It is pointed out that the differences in the semileptonic decay rates, the differences in the Cabibbo suppressed decay rates of the charmed hyperons, and the splitting of the total decay rates of the b hyperons are all related to the differences in the lifetimes of the charmed hyperons independently of poor knowledge of hadronic matrix elements. The approximations used in these relations are the applicability of the expansion…
We consider the predictions of chiral perturbation theory for $SU(3)$ breaking in weak semileptonic and $s$-wave nonleptonic hyperon decays. By defining an expansion sensitive only to $SU(3)$ breaking, we show that the leading corrections give rise to moderate corrections to $SU(3)$ relations ($\lsim 20\%$), even though the {\it chiral} symmetry $SU(3) \times SU(3)$ appears to be rather badly broken. This explains why $SU(3)$ fits to weak hyperon decays work well even though chiral-symmetry breaking corrections are large. Applying these $SU(3)$-breaking corrections to the analysis of the EMC d…
We examine the SU(3) symmetry breaking in hyperon semileptonic decays (HSD) by considering two typical sets of quark contributions to the spin content of the octet baryons: Set-1 with SU(3) flavor symmetry and Set-2 with SU(3) flavor symmetry breaking in HSD. The quark distributions of the octet baryons are calculated with a successful statistical model. Using an approximate relation between the quark fragmentation functions and the quark distributions, we predict polarizations of the octet baryons produced in $e^+e^-$ annihilation and semi-inclusive deeply lepton-nucleon scattering in order t…
The development of chiral perturbation theory in hyperon phenomenology has been troubled due to power-counting subtleties and to a possible slow convergence. Furthermore, the presence of baryon-resonances, e.g. the lowest-lying decuplet, complicates the approach, and the inclusion of their effects may become necessary. Recently, we have shown that a fairly good convergence is possible using a renormalization prescription of the loop-divergencies which recovers the power counting, is covariant and consistent with analyticity. Moreover, we have systematically incorporated the decuplet resonances…
Within the collective coordinate approach to chiral soliton models we suggest that breaking of SU(3) flavor symmetry mainly resides in the baryon wave-functions while the charge operators have no (or only small) symmetry breaking components. In this framework we study the $g_A/g_V$ ratios for hyperon beta-decay as well as the various quark flavor components of the axial charge of the nucleon and the $Λ$-hyperon.
Based on the recent study of the magnetic moments and axial constants within the framework of the chiral quark-soliton model, we investigate the baryon semileptonic decay constants $(f_1,f_2)$ and $(g_1, g_2)$. Employing the relations between the diagonal transition matrix elements and off-diagonal ones in the vector and axial-vector channels, we obtain the ratios of baryon semileptonic decay constants $f_2/f_1$ and $g_1/f_1$. The $F/D$ ratio is also discussed and found that the value predicted by the present model naturally lies between that of the Skyrme model and that of the nonrelativistic…
For the Nambu--Jona--Lasinio (NJL) model in the proper time regularization scheme the chiral soliton is investigated for the case of three flavors within the framework of the bound state approach to strangeness. For this purpose meson fluctuations off the non--strange soliton are considered. For the kaon P--wave channel the emerging Bethe--Salpeter equation is solved yielding the bound state energy and wave--function. This kaon bound state also induces a strange valence quark wave--function. Collective coordinates are introduced for the SU(2) isorotations and the coupling of the bound state to…
The description of baryons as soliton solutions of effective meson theories for three flavor (up, down, strange) degrees of freedom is reviewed and the phenomenological implications are illuminated. In the collective approach the soliton configuration is equipped with baryon quantum numbers by canonical quantization of the coordinates describing the flavor orientation. The baryon spectrum resulting from exact diagonalization of the collective Hamiltonian is discussed. The prediction of static properties such as the baryon magnetic moments and the Cabibbo matrix elements for semi--leptonic hype…
We present results for the hyperon vector form factor f_1 for $Ξ^0 \rightarrow Σ^+ l\barν$ and $Σ^- \rightarrow n l\barν$ semileptonic decays from dynamical lattice QCD with domain-wall quarks. Simulations are performed on the 2+1 flavor gauge configurations generated by the RBC and UKQCD Collaborations with a lattice cutoff of 1/a = 1.7 GeV. Our preliminary results, which are calculated at the lightest sea quark mass (pion mass down to approximately 330 MeV), show that a sign of the second-order correction of SU(3) breaking on hyperon vector coupling f_1(0) is likely negative.
Light-cone QCD sum rules to leading order in QCD are used to investigate the tensor form factors of the $Σ-Σ$, $Ξ-Ξ$ and $ Σ-Λ$ transitions in the range $1 GeV^2 \leq Q^2 \leq 10 GeV^2$. The DAs of $Σ$, $Ξ$ and $Λ$ baryon have been calculated without higher order terms. Then, study including higher order corrections have been done for $Σ$ and $Λ$ baryon. The result of form factors are obtained using these two DAs. We make a comparison with the predictions of the chiral quark soliton model.
The strong and electromagnetic properties of the Lambda(1405) hyperon are studied in the framework of the bound state soliton model. We explicitly evaluate the strong coupling constant g(Lambda^*-N-K), the Lambda^* magnetic moment, mean square radii and radiative decay amplitudes. The results are shown to be in general agreement with available empirical data. A comparison with results of other models is also presented.
We have studied the differential cross section as well as the longitudinal and perpendicular components of polarization of final hyperon($Λ$,$Σ$) produced in the antineutrino induced quasielastic charged current reactions on nucleon and nuclear targets. The nucleon-hyperon transition form factors are determined from the experimental data on quasielastic $(ΔS =0)$ charged current (anti)neutrino--nucleon scattering and the semileptonic decay of neutron and hyperons assuming G--invariance, T--invariance and SU(3) symmetry. The vector transition form factors are obtained in terms of nucleon electr…
We consider the predictions of chiral perturbation theory for $SU(3)$ breaking in the axial vector form factor $g_1$ measured in semileptonic hyperon decays. We confirm that if only octet baryon intermediate states are included, the non-analytic corrections are $\sim 100\%$. These corrections are dominated by an $SU(3)$-symmetric wavefunction renormalization, which explains the fact that the ``corrected'' predictions still fit the data well. We argue that the large corrections are nonetheless strong evidence that this chiral expansion is breaking down. Following a recent suggestion of Jenkins …
Mesonic fluctuations around the chiral solitons are investigated in the SU(3) chiral quark soliton model. Since the soliton takes the non-hedgehog shape for the hyperons and the hedgehog one for the non-hedgehog baryons in our approach, the fluctuations also change according to the baryonic state. The quantum corrections to the masses (the Casimir energies) are estimated for the octet and decuplet baryons. The lack of the confinement in this model demands the cutoff on the energy of the fluctuations. Under the assumption that the value of the cutoff energy is $2\times$(the lightest constituent…
