Program: GN-2015A-FT-22

The Diffuse Interstellar absorption Bands (DIBs) have defied a convincing identification despite being discovered almost a century ago. We now know of hundreds of DIBs in the UV, visible and (most recently) near-IR. They are almost certainly molecular in origin, and modeling of band profiles offers powerful constraints on molecular constants. Polycyclic aromatic hydrocarbons (PAHs) have near-IR transitions and appear to be plausible carriers for the near-IR bands. Herschel 36, the illuminating star of the Lagoon Nebula, has recently been shown to possess uniquely broad and asymmetric DIB profiles in the visible, and is bright enough to observe in the near-IR. We propose to use GNIRS to obtain the first high-resolution spectroscopy of two near-IR DIBs in this object, which may conclusively link the NIR DIBs to those seen in the visible.