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We produce a catalogue of polycyclic aromatic hydrocarbon (PAH) 3.3 $\mu$m,Br$\alpha$ and infrared luminosity ($L$(IR)) of 412 local galaxies, andinvestigate a relation between these physical parameters. We measure the PAH3.3 $\mu$m and Br$\alpha$ flux using AKARI 2-5 $\mu$m spectra and the $L$(IR)using the AKARI-all-sky-survey data. The $L$(IR) and redshift ranges of oursample are $L$(IR)=$10^{9.7-12.8}$L$_\odot$ and $z_{\rm spec}=0.002-0.3$,respectively. We found that the ratio of $L$(PAH 3.3 $\mu$m) to $L$(IR) isconstant at $L$(IR) $<$ $10^{11} \rm L_\odot$ whereas it decreases with the$L$(IR) at higher $L$(IR). Also, the ratio of $L$(Br$\alpha$) to $L$(IR)decreases with the $L$(IR). The both $L$(PAH)/$L$(IR) and$L$(Br$\alpha$)/$L$(IR) ratios are not strongly dependent on galaxy type anddust temperature. The relative weakness of the two ratios could be attributedto destruction of PAH, a lack of UV photons exciting PAH molecules or ionisinghydrogen gas, extremely high dust attenuation, or active galactic nucleuscontribution to the $L$(IR). Although we cannot determine the cause of thedecreases of the luminosity ratios, a clear correlation between them impliesthat they are related with each other. The catalogue presented in our work willbe available at the AKARI archive web page.

Relation between polycyclic aromatic hydrocarbon, Br$\alpha$ and infrared luminosity of local galaxies observed with AKARI