We provide results of near-infrared (NIR) spectroscopic observations of 83 nearby (0.002< z <0.48) and bright (K <14 mag) type 1 active galactic nuclei (AGNs). For the observations, we used the Infrared Camera (IRC) on AKARI allowing us to obtain the spectrum in the rarely studied spectral range of 2.5-5.0 μm. The 2.5-5.0 μm spectral region suffers less dust extinction than ultra violet (UV) or optical wavelength ranges, and contains several important emission lines such as Brβ (2.63 μm), Brα (4.05 μm), and polycyclic aromatic hydrocarbon (PAH; 3.3 μm). The sample is selected from the bright quasar surveys of Palomar Green and SNUQSO, and AGNs with black hole (BH) masses estimated from rever- beration mapping method. We measure the Brackett line properties for 11 AGNs, which enable us to derive BH mass estimators and investigate circum-nuclear environments. Moreover, we perform spectral modeling to fit the hot and warm dust components by adding photometric data from SDSS, 2MASS, WISE, and ISO to the AKARI spectra, and estimate hot and warm dust temperatures of ~1100K and ~220 K, respectively.

ABSTRACT
1. INTRODUCTION
2. RESULTS
    2.1. BH Mass Estimators with Brackett Lines
    2.2. Dust Component
3. SUMMARY
REFERENCES

• Dohyeong Kim(Astronomy Program, Department of Physics and Astronomy, Seoul National University)
• Myungshin Im(Astronomy Program, Department of Physics and Astronomy, Seoul National University)
• QSONG team(Astronomy Program, Department of Physics and Astronomy, Seoul National University)