Altas Energías

Extracting a data driven magnetic dipole moment for the $\rho$ meson

by Dr. Genaro Toledo (Instituto de Fisica, UNAM)

Wednesday, 12 March 2025 from to (Mexico/General)
at ICN-UNAM ( Salón de Seminarios de Gravitación y Física de Altas Energías, A225 )
Description
We obtain the value of the magnetic dipole moment of the $\rho$ meson, using data from the BaBar Collaboration for the $e^{+} e^{-} \to \pi^+ \pi^- 2 \pi^0$ process. The considered center of mass energy range is from 0.9 to 1.8 GeV. We describe the $\gamma^* \to 4\pi$ vertex using a vector meson dominance model, including the intermediate resonant contributions relevant at these energies. We find $\mu_\rho = 2.7 \pm 0.3 $ in $e/2 m_\rho$ units. We improve on the previous extracted value, where preliminary data from the same collaboration was used, by considering definite data, better grounded values of the parameters involved and explicit gauge invariant description of the process.
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