Neutron-Capture elements in planetary nebulae: first detections of near-Infrared [Te III] and [Br V] emission lines

Understand

We have identified two new near-infrared emission lines in the spectra of planetary nebulae (PNe) arising from heavy elements produced by neutron capture reactions: [Te III] 2.1019 $\mu$m and [Br V] 1.6429 $\mu$m.

• [Te III] was detected in both NGC 7027 and IC 418, while [Br V] was seen in NGC 7027.
• The observations were obtained with the medium-resolution spectrograph EMIR on the 10.4m Gran Telescopio Canarias at La Palma, and with the high-resolution spectrograph IGRINS on the 2.7m Harlan J.
• Smith telescope at McDonald Observatory.