Young Galactic supernova remnants (SNRs) are where we can observe closely supernova (SN) ejecta and their interaction with the circumstellar/interstellar medium. They also provide an opportunity to explore the explosion and the final stage of the evolution of massive stars. Near-infrared (NIR) emission lines in SNRs mostly originate from shocked dense material. In shocked SN ejecta, forbidden lines from heavy ions are prominent, while in shocked circumstellar/interstellar medium, [Fe II] and H2 lines are prominent. [Fe II] lines are strong in both media, and therefore [Fe II] line images provide a good starting point for the NIR study of SNRs. There are about twenty SNRs detected in [Fe II] lines, some of which have been studied in NIR spectroscopy. We will review the NIR [Fe II] observations of SNRs and introduce our recent NIR spectroscopic study of the young core-collapse SNR Cas A where we detected strong [P II] lines.

ABSTRACT
1. INTRODUCTION
2. NIR [Fe II] EMISSION FROM SNRs
3. NIR [Fe II] AND [P II] EMISSION FROM Cas A
    3.1. NIR Spectroscopy of Cas A
    3.2. [P II] lines in Cas A and SN Nucleosynthesis
    3.3. [P II] lines for the ISM Study
4. SUMMARY
REFERENCES

• Bon-Chul Koo(Seoul National University)
• Yong-Hyun Lee(Seoul National University)