Search results for "baryons"
showing 10 items of 82 documents
Masses of doubly charmed baryons in the extended on-mass-shell renormalization scheme
2016
In this work, we investigate the mass corrections of the doubly charmed baryons up to $N^2LO$ in the extended-on-mass-shell (EOMS) renormalization scheme, comparing with the results of heavy baryon chiral perturbation theory. We find that the terms from the heavy baryon approach are a subset of those obtained in the EOMS scheme. By fitting the lattice data, we can determine the parameters $\tilde{m}$, $\alpha$, $c_1$ and $c_7$ from the Lagrangian, while in the heavy baryon approach no information on $c_1$ can be obtained from the baryons mass. Correspondingly, the masses of $m_{\Xi_{cc}}$ and $m_{\Omega_{cc}}$ are predicted, in the EOMS scheme, extrapolating the results from different value…
Ab initio three-loop calculation of the W -exchange contribution to nonleptonic decays of double charm baryons
2019
We have made an ab initio three-loop quark model calculation of the $W$-exchange contribution to the nonleptonic two-body decays of the doubly charmed baryons $\Xi_{cc}^{++}$ and $\Omega_{cc}^{+}$. The $W$-exchange contributions appear in addition to the factorizable tree graph contributions and are not suppressed in general. We make use of the covariant confined quark model previously developed by us to calculate the tree graph as well as the $W$-exchange contribution. We calculate helicity amplitudes and quantitatively compare the tree graph and $W$-exchange contributions. Finally, we compare the calculated decay widths with those from other theoretical approaches when they are available.
Observation of the Baryonic Flavor-Changing Neutral Current Decay Λb0→Λμ+μ-
2011
8 páginas, 2 figuras, 4 tablas.-- PACS numbers: 13.30.Ce, 12.15.Mm, 14.20.Mr.-- CDF Collaboration: et al.
Magnetic moments of heavy baryons
2000
6 páginas, 2 figuras, 4 tablas.-- PACS number(s): 12.39.Fe, 12.39.Hg, 14.20.Lq, 14.20.Mr
Spectra of the lightest baryons containing two heavy quarks in a potential model
2000
The spectra of baryons which include two heavy quarks can be treated as a two-body system, where the two heavy quarks constitute a bosonic diquark. We derive the effective potential between the light quark and the heavy diquark in terms of the Bethe-Salpeter equation. To obtain the spectra, several serious problems need to be solved: (1) the operator ordering, (2) the errors caused by the nonrelativistic expansion, (3) spin-spin coupling, and (4) the mixing between the scalar-diquark-baryon and vector-diquark-baryon. In this work we take reasonable approaches to deal with them.
Prediction of NarrowN*andΛ*Resonances with Hidden Charm above 4 GeV
2010
Up to now, all established baryons can be ascribed into 3-quark (qqq) configurations [1], although some of them were suggested to be meson-baryon dynamically generated states [2–8] or states with large (qqqq¯ q) components [9–11]. A difficulty to pin down the nature of these baryon resonances is that the predicted states from various models are around the same energy region and there are always some adjustable ingredients in each model to fit the experimental data. In this letter, we report a study of the interactions between various charmed mesons and charmed baryons within the framework of the coupled channel unitary approach with the local hidden gauge formalism. Several meson-baryon dyn…
Spin, helicity and flavour patterns in exclusive decays of bottom mesons into baryon-antibaryon pairs
1989
I use the constituent quark model to calculate the exclusive decays of bottom mesons into ground state baryon-antibaryon pairs mediated by the weakb→c and b→u transitions. TheW-exchange contributions to these decays are found to be negligible. For theW-decay contributions I find that the simple colour-flavour structure of the 1/2+ and 3/2+ ground state baryons together with the current-current nonleptonic Hamiltonian leads to many simple and testable predictions. Notable among these is the predicted vanishing of decays involving 3/2+ baryons as in\(\overline {B^0 } (B^ - ) \to 3/2^ + \overline {1/2^ + } \) and\(\overline {B^0 } (B^ - ) \to 3/2^ + \overline {3/2^ + } \). An experimental veri…
Faddeev study of heavy baryon spectroscopy
2007
16 pages, 3 figures.-- PACS nrs.: 12.39.Jh, 12.39.Pn, 14.20.-c.-- ISI Article Identifier: 000246249100015.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0703257
Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons
2010
We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way.
Exotic dynamically generated baryons with negative charm quantum number
2010
Following a model based on the SU(8) symmetry that treats heavy pseudoscalars and heavy vector mesons on an equal footing, as required by heavy quark symmetry, we study the interaction of baryons and mesons in coupled channels within an unitary approach that generates dynamically poles in the scattering T-matrix. We concentrate in the exotic channels with negative charm quantum number for which there is the experimental claim of one state.