0000000000697670
AUTHOR
M. Pavon Valderrama
showing 4 related works from this author
Decay widths of the spin-2 partners of the X (3872)
2015
We consider the $X(3872)$ resonance as a $J^{PC}=1^{++}$ $D\bar D^*$ hadronic molecule. According to heavy quark spin symmetry, there will exist a partner with quantum numbers $2^{++}$, $X_{2}$, which would be a $D^*\bar D^*$ loosely bound state. The $X_{2}$ is expected to decay dominantly into $D\bar D$, $D\bar D^*$ and $\bar D D^*$ in $d$-wave. In this work, we calculate the decay widths of the $X_{2}$ resonance into the above channels, as well as those of its bottom partner, $X_{b2}$, the mass of which comes from assuming heavy flavor symmetry for the contact terms. We find partial widths of the $X_{2}$ and $X_{b2}$ of the order of a few MeV. Finally, we also study the radiative $X_2\to …
Heavy Quark Symmetries: Molecular Partners of the X(3872) and $Z_{b}(10610)/Z_{b}'(10650)$
2013
In this work, we have used an Effective Field Theory (EFT) framework based on Heavy Quark Spin (HQSS), Heavy Flavour (HFS) and Heavy Antiquark-Diquark symmetries (HADS). Using a standard lagrangian for the heavy meson-heavy antimeson system, we fit the counter-terms of the model to predict some promising experimental data that can be interpreted as heavy meson-heavy antimeson molecules, that is, the X(3872) and the $Z_{b}(10610)/Z'_{b}(10650)$. Next, and, taking advantage of HADS, we use the same lagrangian to explore the consequences for heavy meson-doubly heavy baryon molecules, which can also be interpreted as triply heavy pentaquarks.
Inverse amplitude method in pi pi scattering in chiral perturbation theory to two loops
2002
The inverse amplitude method is used to unitarize the two loop $\pi\pi$ scattering amplitudes of SU(2) Chiral Perturbation Theory in the $I=0,J=0$, $I=1,J=1$ and $I=2,J=0$ channels. An error analysis in terms of the low energy one-loop parameters $\bar l_{1,2,3,4,}$ and existing experimental data is undertaken. A comparison to standard resonance saturation values for the two loop coefficients $\bar b_{1,2,3,4,5,6} $ is also carried out. Crossing violations are quantified and the convergence of the expansion is discussed.
Heavy meson-antimeson molecules in effective field theory: The role of one pion exchange and heavy quark spin symmetry
2012
In this contribution we study heavy meson-antimeson molecules from the effective field theory perspective. In particular, we are concerned with the role of the one pion exchange interaction and heavy quark spin symmetry in the description of molecular states. As we will show, one pion exchange is in general a perturbative effect. This means that at lowest order we can describe the molecular states in terms of contact interactions only, a remarkable simplification. The application of heavy quark spin symmetry will be very interesting, as we will be able to predict new heavy meson-antimeson bound states from known ones. For instance, if we assume that the X(3872) is in fact a JPC = 1++ DD/DD …