相关论文: QCD Sum Rule for 1/2- Baryons

Masses and couplings of the negative parity excited baryons are studied in the QCD sum rule. Separation of the negative-parity spectrum is proposed and is applied to the flavor octet and singlet baryons. We find that the quark condensate is…

We apply the method of the QCD sum rule, in which positive- and negative-parity baryons couple with each other, to the flavor-octet hyperons and investigate the parity splittings. We also reexamine the nucleon in the method, which was…

N* masses in the spin-1/2 and spin-3/2 sectors are computed using two non-perturbative methods: lattice QCD and QCD sum rules. States with both positive and negative parity are isolated via parity projection methods. The basic pattern of…

The masses of octet baryons are calculated by the method of QCD sum rules. Using generalized interpolating fields, three independent sets of QCD sum rules are derived which allow the extraction of low-lying N* states with spin-parity 1/2+,…

The negative-parity baryons are studied by a novel approach in the QCD sum rule. It is found that the parity of the ground-state nucleon is determined by the sign of the quark condensate. We predict the mass of negative-parity nucleon.

We study the recently observed $\Omega(2012)$ baryon in QCD sum rules. We construct the $P$-wave $\Omega$ baryon currents with a covariant derivative, and perform spin projection to obtain the currents with total spin 1/2 and 3/2. We then…

We investigate the recently observed $\Omega(2012)$ baryon using QCD sum rules. By constructing $P$-wave $\Omega$ baryon currents and performing spin projection and parity projection, we obtain the masses of the $J^P = 1/2^-$ and $3/2^-$…

We use the QCD sum rule approach to calculate the masses of the Lambda_Q and Sigma_Q baryons to the Lambda_{QCD}/m_Q order within the framework of heavy quark effective theory. We compare the direct approach and the covariant approach to…

We study the P-wave bottom baryons using the method of QCD sum rule and heavy quark effective theory. Our results suggest that Lambda_b(5912) and Lambda_b(5920) can be well described by the baryon doublet [3F_bar, 1, 1, rho], and they…

We use the method of QCD Sum Rules to estimate the masses of the charm baryon, $\Lambda^+_c$, bottom baryon $\Lambda^0_b$, strange baryon $\Lambda^0_s$ and compare them to their experimental values.

A calculation of the mass spectrum in the baryon decuplet sector is presented using the method of QCD sum rules. Sum rules are derived for states of spin-parity 3/2+- and 1/2+ using both the conventional method and a parity-projection…

The mass spectra of strange baryons in the octet family are investigated in a finite-energy QCD sum rule approach based on the Gauss-Weierstrass transform. The phenomenological form of the spectral function is saturated by the ground state…

We have calculated the mass spectra of nucleon and delta hybrid baryons with both positive-parity and negative-parity by using the method of QCD sum rules. We predicte that the lowest-lying hybrid baryons are the negative-parity $N_{1/2^-}$…

Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the neutron-proton, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences. Provided the…

The spectroscopic properties of single heavy spin-1/2 $\Lambda_{Q}$, $\Sigma_{Q}$, $\Xi^{(\prime)}_{Q}$ and $ \Omega_{Q}$ baryons are investigated at finite temperature in the framework of thermal QCD sum rule. We discuss the behavior of…

Using the QCD sum rule method, we investigate the mass splitting for the spin-orbit partner states of the $\Omega(2012)$ baryon assuming that it is a $P$-wave excitation with $J^P=3/2^-$. This study is an extension of the previous work [1]…

We use QCD sum rule approach to calculate the masses of the ground-state Lambda_Q and Sigma_Q^(*) baryons. Contributions of the operators up to dimension six are included in operator product expansion. The resulting heavy baryonic masses…

Masses of the p-wave excited heavy baryons have been calculated to the Lambda_{QCD}/m_Q order using QCD sum rule method within the framework of heavy quark effective theory. Numerical results for kinetic energy lambda_1 and chromo-magnetic…

The approximate chiral invariance of the two-flavor QCD is known to be spontaneously broken. This effect explains the relatively small pion mass and, as is widely believed, the mass splittings of would-be chiral partners --- the hadrons of…

We use QCD sum rules to study the masses of the baryons $\Xi_c$ and $\Xi_b$. We work with a current where the strange and the light quarks are in a relative spin zero, at leading order in $\alpha_s$. We consider the contributions of…