Near infrared and ultraviolet spectra of TLEs

We have found that sprites, beads and halos have similar optical spectra, but measurable differences in the near IR and near UV spectra. In particular, near infrared (NIR) and ultraviolet (UV) spectra of sprites, halos and beads corresponding to the first (1PG) and second positive (2PG) bands of N 2 have been calculated for different observation altitudes from mountains (3.25 km) to airplanes (14 km), balloons (35 km) and space (nadir) platforms. The calculated non‐equilibrium vibrational distribution functions (VDF) of the N 2 ( B 3 Π g ) states in halos and beads show that the calculated NIR emissions produced through strong N 2 ‐1PG (B 3 Π g → A 3 Σ u + ) transitions differ from the calculated sprite spectral emission patterns at ∼888 nm but particularly pronounced differences are found in the NIR spectral region at ∼1046 nm and ∼1231 nm corresponding to the N 2 ‐1PG (0,0) and (0,1) transitions, respectively. The blue ‐ near UV spectra from N 2 ‐2PG (C 3 Π u → B 3 Π g ) transitions in halos and beads also exhibits slightly different spectral features when compared to the blue ‐ near UV spectrum of sprites for bands originating from higher v ‐levels ( v > 0) although they might not be above electronic noise level to be distinguished.