On the possibility of the existence of NO+ in interstellar space

Frequencies are computed for transitions in the NO⁺ ion which are expected to occur in the millimeter and infrared regions usually covered by millimeter-wave and infrared astronomy. The emission cross-sections and spontaneous emission rates of the microwave transitions of NO⁺ ion are presented. The NO⁺ molecule is likely to be detectable in low-temperature sources whose state temperatures are not greater than 15 K. Transition probabilities and oscillator strengths for the v=1, 2, 3 and 4 vibration-rotation bands are derived from published theoretical dipole moment functions, obtained by an accurate multi-configuration self-consistent field procedure, in the¹ ground state of NO⁺ ion. On the basis of binary gas phase reactions, the formation and destruction of NO⁺ in interstellar space are also discussed.Work partially supported by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq, Brazil, under processo 1111.4076/77-FA.