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Carlos E. Sandoval

Publications and source records attributed to Carlos E. Sandoval.

5 recordsLinked to original sources
arXiv2005

Improving bounds on flavor changing vertices in the two Higgs doublet model from $B-\bar{B}$ mixing

We find some constraints on the flavor changing vertices of the two Higgs doublet model, from the ΔM_{B_{d}} measurement. Although bounds from this observable have already been considered, this paper takes into account the role of a new operator not included previously, as well as the vertices ξ_{bb}, ξ_{tc} and ξ_{sb}. Using the Cheng-Sher parametrization, we found that for a relatively light charged Higgs boson (200-300 GeV), we get that λ_{tt}<1, while the parameter λ_{bb} could have values up to about 50. In addition, we use bounds for λ_{tt} and λ_{bb} obtained from B^{0}->X_{s}γat next to leading order, and studied the case where the only vanishing vertex factors are the ones involving quarks from the first family. We obtained that ΔM_{B_{d}} is not sensitive to the change of the parameter λ_{sb}, while λ_{tc}<1

hep-ph↗
arXiv2005

A covariant model of the electromagnetic current for the study of two-body scalar systems

We present a procedure to derive a covariant electromagnetic current operator for a system made up by two scalars constituents. Using different wave functions we fitted their parameters to the experimental data of the pion form factor, obtainig great discrepancy at low momentum transfer. Introducing the Vector Meson Dominance corrective factor, we obtained a better fit to the data.

nucl-th↗
arXiv2004

Flavor changing neutral currents from lepton and B decays in the two Higgs doublet model

Constraints on the whole spectrum of lepton flavor violating vertices are shown in the context of the standard two Higgs doublet model. The vertex involving the $e-τ$ mixing is much more constrained than the others, and the decays proportional to such vertex are usually very supressed. On the other hand, bounds on the quark sector are obtained from leptonic decays of the $B_{d,s}^{0}$ mesons and from $ΔM_{B_{d}^{0}}$. We emphasize that although the $B_{d}^{0}-\bar{B}_{d}^{0}$ mixing restricts severely the $% d-b$ mixing vertex, the upper bound for this vertex could still give a sizeable contribution to the decay $B_{d}^{0}\to μ\barμ$ respect to the standard model contribution, from which we see that such vertex could still play a role in the phenomenology.

hep-ph↗
arXiv2003

Constraints on lepton flavor violation in the two Higgs doublet model

Constraints on the whole spectrum of lepton flavor violating vertices are shown in the context of the standard two Higgs doublet model. The vertex involving the $e-τ$ mixing is much more constrained than the others, and the decays proportional to such vertex are usually very suppressed.

hep-ph↗