相关论文: Predictions for masses of bottom baryons
The recent observation at the Tevatron of $\Sigma_b^{\pm}$ ($uub$ and $ddb$) baryons within 2 MeV of the predicted $\Sigma_b - \Lambda_b$ splitting and of $\Xi_b^-$ $(dsb)$ baryons at the Tevatron within a few MeV of predictions has…
The recent observation by CDF of Sigma_b^{+-} (uub and ddb) baryons within 2 MeV of the predicted Sigma_b - Lambda_b splitting has provided strong confirmation for the theoretical approach based on modeling the color hyperfine interaction.…
We report an observation of new bottom baryons produced in proton-antiproton collisions at the Tevatron. Using 1.1 fb^{-1} of data collected by the CDF II detector, we observe four \Lambda_b^0\pi^{\pm} resonances in the fully reconstructed…
The recent measurement by CDF M(Sigma_b)-M(Lambda_b)=192 MeV is in striking agreement with our theoretical prediction M(Sigma_b)-M(Lambda_b) = 194 MeV. In addition, the measured splitting M(Sigma_b*)-M(Sigma_b) = 21 MeV agrees well with the…
We use the method of QCD sum rules within the framework of heavy quark effective theory to study the mass spectrum of the $\Sigma_{b}(6097)^{\pm}$ and $\Xi_{b}(6227)^{-}$, and use the method of light-cone sum rules still within the heavy…
The large number of $B_c$ mesons observed by LHCb suggests a sizable cross section for producing doubly-heavy baryons in the same experiment. Motivated by this, we estimate masses of the doubly-heavy $J=1/2$ baryons $\Xi_{cc}$, $\Xi_{bb}$,…
Bottom baryons decaying to a J/\psi\ meson and a hyperon are reconstructed using 1.0 fb^{-1} of data collected in 2011 with the LHCb detector. Significant \Lambda_b^0 \rightarrow J/\psi \Lambda, \Xi_b^-\rightarrow J/\psi \Xi^- and…
We study the $\Lambda_b(6146)^0$ and $\Lambda_b(6152)^0$ recently observed by LHCb using the method of QCD sum rules within the framework of heavy quark effective theory. Our results suggest that they can be interpreted as $D$-wave bottom…
Following recent experimental progress in the study of bottom baryons, we systematically calculate the mass spectra of $\Lambda_{b}$, $\Xi_{b}$, $\Sigma_{b}$, $\Xi_{b}^{'}$, and $\Omega_{b}$ baryons with a quark-diquark picture in the…
Using data from proton - anti-proton collisions at the energy Ecm = 1.96 TeV recorded by the CDF II detector at the Fermilab Tevatron, we present improved measurements of the masses and first measurements of natural widths of the four…
The LHCb Collaboration has recently observed two narrow baryon resonances with beauty. Their masses and decay modes look consistent with the quark model orbitally excited states Lambda_b(5912) and Lambda*_b(5920), with quantum numbers…
Recently LHCb reported the discovery of four extremely narrow excited $\Omega_b$ baryons decaying into $\Xi_b^0 K^-$. We interpret these baryons as bound states of a $b$-quark and a $P$-wave $ss$-diquark. For such a system there are exactly…
The Feynman-Hellmann theorem and semiempirical mass formulas are used to predict the masses of baryons containing one or two heavy quarks. In particular, the mass of the $\Lambda_b$ is predicted to be $5620 \pm 40$ MeV, a value consistent…
The LHCb Experiment at CERN has observed a doubly-charmed baryon $\Xi_{cc}^{++} =ccu$ with a mass of $3621.40 \pm 0.78$ MeV, consistent with many predictions. We use the same methods that led us to predict $M(\Xi_{cc},~J^P{=}1/2^+) = 3627…
The recent observation at CDF and D0 of $\Sigma_b$, $\Sigma^*_b$ and $\Xi_b$ baryons opens the door to the advent of new states in the bottom baryon sector. The states measured provide sufficient constraints to fix the parameters of…
The strong decays of the $P$-wave $\Sigma_b$, $\Xi_b'$ and $\Omega_b$ baryons are investigated with a constituent quark model in the $j$-$j$ coupling scheme. The results show that the newly observed $\Sigma_b(6097)$ and $\Xi_b(6227)$ states…
The methods of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory have been widely applied to study the singly heavy baryons, and especially, we have applied these methods to predict not only the…
We present properties of weakly decaying bottom baryons, Xi_b and Omega_b, using 4.2 fb^-1 of data from p-pbar collisions at sqrt{s}=1.96 TeV, and recorded with the Collider Detector at Fermilab. We report the observation of the Omega_b…
We report the observation of new bottom baryon states. The most recent result is the observation of the baryon \Xi_b^- through the decay \Xi_b^- to J/\psi \Xi^-. The significance of the signal corresponds to 7.7 sigma and the \Xi_b^- mass…
Recently LHCb discovered the first doubly-charmed baryon $\Xi_{cc}^{++} = ccu$ at $3621.40 \pm 0.78$ MeV, very close to our theoretical prediction. We use the same methods to predict a doubly-bottom tetraquark $T(bb\bar u\bar d)$ with…