The discussion centers on the high thermal neutron cross section of the isotope 135Xe, with participants noting that this characteristic appears to be a coincidence of nature. In contrast, isotopes Xe-134 and Xe-136 exhibit very low absorption cross-sections and are stable. Comparisons are drawn to rare Earth isotopes like Sm-149, -151 and Gd-155, -157, which have similar absorption properties. The presence of suitable excited states, whether real or virtual, is suggested as a common factor influencing these cross-sections. Overall, the unique behavior of 135Xe in neutron interactions remains a topic of interest in nuclear physics.
