Resumen de Excitations of H2 by positron impact (6 pages)
In this paper, we present a theoretical study of scattering cross sections for positron impact of electronic states of hydrogen molecule (H_(2)) using the scaling Born positron (SBP) approach. Cross sections to low-lying electronic states, B^(1)∑^(+)_(u), C^(1)Π_(u), B^(′1)∑^(+)_(u), and D^(1)Π_(u) are investigated. In an earlier theoretical effort [J.L.S.Lino,Rev. Mex. Fis.62(2016) 596], an application of the SBP approach for the X^(1)∑^(+)_(g) → B^(1)∑^(+)_(u) electronic excitation of the H_(2) molecule, gave cross sections with reasonable qualitative agreement with experimental data [J.P. Sullivanet al., Phys. Rev. Lett.87(2001) 073201]. However, recent studies for the excitation of the B^(1)∑^(+)_(u) state by positrón impact showed that this electronic state still demand of a refined degree of description of the quality of the cross sections (Weisset al., Eur.Phys. J.D(2018) 72). The purpose of this work was to reexamine the B^(1)∑^(+)_(u) state and verify the quality of the numerical convergence of SBP method and extend the investigation to other states. The possibility to estimate a indirect contribution of multichannel effects (thre estates considering the ground X1, B^(1)∑^(+)_(u) and E, F^(1)∑^(+)_(u) state) are introduced within the SBP context. For the first time, integral cross sections to these new states using the SBP approach are reported. In the absence of the experimental data and theoretical developments, comparisons are made with analogous electron scattering.
