El Cuerpo Académico de Partículas Campos y Relatividad General invita cordialmente a su próximo seminario

Spin physics with strange hadrons: polarization and spin alignment

Dr. Eleazar Cuautle Flores
Instituto de Ciencias Nucleares, UNAM
(En estancia sabática en la FCFM, BUAP)

Este seminario se llevará a cabo en la

Sala de Conferencias 111B/302
Miércoles 6 de junio de 2012
12:00 hrs.




Polarization may provide valuable insights into the evolution of the system, the hadronization mechanism, and the origin of hadronic spin preferences. The present talk discuss a production mechanism from which the $\Lambda^0$ polarization in $pp$ collisions could be explained and predictions for Lead-Lead are presented. The method used in $\Lambda^0$ polarization, can be used in similar way to estimate the spin alignment of the vector mesons $K^{*0}$ and $\phi(1020)$ reported by STAR at RHIC. These measurements are consistent with the absence of spin alignment with respect to the reaction plane, whereas when it is measured with respect to the production plane, a non-zero and transverse momentum dependent spin alignment is found in mid-central Au + Au collisions. We explain these results in terms of a simple model of vector meson production where the spin of their constituent quarks is oriented during hadronization as the results of Thomas precession. The model is then used to predict the spin alignment for other vector mesons such as $\rho^0$ and $\omega$.