Slow electron elastic scattering cross sections for In, Tl, Ga and At atoms

The complex angular momentum (CAM)-calculated, low-energy 0 <= E <= 5 eV electron elastic total cross section (TCS) for In is benchmarked through its recently measured electron affinity in Walter et al (2010 Phys. Rev. A 82 032507). The TCSs for Tl, Ga and At atoms are then calculated using the CAM method. From the dramatically sharp resonances in the TCSs, binding energies for Tl-, Ga- and At-negative ions formed during the collisions as Regge resonances are extracted and compared with the existing experimental and theoretical values.