Bright Type II Supernova 2023ixf in M101: A Quick Analysis of the Early-Stage Spectra and Near-Infrared Light Curves

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We present early-stage analyses of low-resolution ($R=1000$) optical spectra and near-infrared light curves of the bright Type II supernova (SN II) 2023ixf in the notable nearby face-on spiral galaxy M101, which were obtained from $t=1.7$ to $8.0$ d.

• Our first spectrum showed remarkable emission features of Balmer series, He~{\sc ii}, N~{\sc iii}, C~{\sc iv}, and N~{\sc iv} with a strong blue continuum.
• Compared with the SNe II showing flash-ionized features, we suggest that this SN could be categorized into the high-luminosity SNe II with a nitrogen/helium-rich circumstellar material (CSM), e.g., SNe 2014G, 2017ahn, and 2020pni.
• The H~{$\alpha$} emission line can be tentatively explained by a narrower component with a velocity of $<300$ km~s$^{-1}$ and a broader one with $\sim2200$ km~s$^{-1}$.