0000000000893445
AUTHOR
Aurora Melis
Masses and decay constants of D(s)* and B(s)* mesons with Nf=2+1+1 twisted mass fermions
We present a lattice calculation of the masses and decay constants of ${D}_{(s)}^{*}$ and ${B}_{(s)}^{*}$ mesons using the gauge configurations produced by the European Twisted Mass Collaboration (ETMC) with ${N}_{f}=2+1+1$ dynamical quarks at three values of the lattice spacing $a\ensuremath{\sim}(0.06\ensuremath{-}0.09)\text{ }\text{ }\mathrm{fm}$. Pion masses are simulated in the range ${M}_{\ensuremath{\pi}}\ensuremath{\simeq}(210--450)\text{ }\text{ }\mathrm{MeV}$, while the strange and charm sea-quark masses are close to their physical values. We compute the ratios of vector to pseudoscalar masses and decay constants for various values of the heavy-quark mass ${m}_{h}$ in the range $0…
HQE parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses
We present a new lattice determination of some of the parameters appearing both in the Operator Product Expansion (OPE) analysis of the inclusive semileptonic $B$-meson decays and in the Heavy Quark Expansion (HQE) of the pseudoscalar (PS) and vector (V) heavy-light meson masses. We perform a lattice QCD (LQCD) computation of PS and V heavy-light meson masses for heavy-quark masses $m_h$ in the range from $m_c^{\rm phys}$ to $\simeq 4m_b^{\rm phys}$. We employed the $N_f = 2+1+1$ gauge configurations of the European Twisted Mass Collaboration (ETMC) at three values of the lattice spacing $a \simeq (0.062, 0.082, 0.089)$ fm with pion masses in the range $M_\pi \simeq (210 - 450)$ MeV. The he…
The Origin of Flavor in Physics Beyond the Standard Model
En esta disertación, investigamos la interacción entre la supersimetría y los modelos basados en diferentes grupos de simetría de sabor: A4, S3, A5 y Δ (27). Aunque su capacidad de predicción depende de ellos, el SM no da pistas sobre el valor de ninguno de sus parámetros de sabor. Pueden considerarse insumos externos necesarios del modelo. Esto se conoce con el nombre de puzzle de sabor. Entre las ideas propuestas para abordar el rompecabezas del sabor, el uso de simetrías de sabor, desde el mecanismo más simple de Froggatt Nielsen (FN) hasta simetrías discretas no abelianas, sigue siendo la herramienta más popular para los constructores de modelos. Esta avenida se ha explorado especialm…
Extraction of heavy-quark-expansion parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses
We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to $\ensuremath{\simeq}4$ times the physical $b$-quark mass. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with ${N}_{f}=2+1+1$ dynamical quarks at three values of the lattice spacing ($a\ensuremath{\simeq}0.062,0.082,0.089\text{ }\text{ }\mathrm{fm}$) with pion masses in the range ${M}_{\ensuremath{\pi}}\ensuremath{\simeq}210--450\text{ }\text{ }\mathrm{MeV}$. The heavy-quark mass is simulated directly on the lattice up to $\ensuremath{\simeq}3$ times the physical charm mass. The interpol…
Anomaly-free leptophilic axionlike particle and its flavor violating tests
Motivated by the recent Xenon1T result, we study a leptophilic flavor-dependent anomaly-free axionlike particle (ALP) and its effects on charged-lepton flavor violation. We present two representative models. The first one considers that the ALP origins from the flavon that generates the charged-lepton masses. The second model assumes a larger flavor symmetry such that more general mixings in the charged-lepton are possible, while maintaining flavor-dependent ALP couplings. We find that a keV ALP explaining the Xenon1T result is still viable for lepton flavor violation and stellar cooling astrophysical limits. On the other hand, if the Xenon1T result is confirmed, future charged-lepton flavo…