2019AJ....157..123L

We report the detection of near-infrared (NIR) [Fe II] (1.644 µm) and H₂ 1-0 S(1) (2.122 µm) line features associated with Galactic supernova remnants (SNRs) in the first quadrant using two narrowband imaging surveys, UWIFE and UWISH2. Among the total of 79 SNRs fully covered by both surveys, we found 19 [Fe II]-emitting and 19 H₂-emitting SNRs, giving a detection rate of 24% for each. Eleven SNRs show both emission features. The detection rate of [Fe II] and H₂ peaks at the Galactic longitude (l) of 40°-50° and 30°-40°, respectively, and gradually decreases toward smaller/larger l. Five out of the eleven SNRs emitting both emission lines clearly show an "[Fe II]-H₂ reversal," where H₂ emission features are found outside the SNR boundary in [Fe II] emission. Our NIR spectroscopy shows that the H₂ emission originates from collisionally excited H₂ gas. The brightest SNR in both [Fe II] and H₂ emissions is W49B, contributing more than 70% and 50% of the total [Fe II] 1.644 µm (2.0 x 10⁴ L_☉) and H₂ 2.122 µm (1.2 x 10³ L_☉) luminosities of the detected SNRs. The total [Fe II] 1.644 µm luminosity of our Galaxy is a few times smaller than that expected from the SN rate using the correlation found in nearby starburst galaxies. We discuss possible explanations for this.