NEAR-INFRARED SURFACE PHOTOMETRY OF 60-MICRON-PEAKER GALAXIES

Near-infrared (NIR) photometry of a sample of 31 'warm' IRAS galaxies whose spectral energy distribution peaks in the 60-mu m band - Sixty M icron Peakers - is presented. Radial surface brightness profiles revea l that most are dominated by a bulge component in the NIR, indicative of early-type host galaxies. The distribution of the bulge effective r adius in the K band is similar to LINERS and starbursts, but very diff erent from optically selected Seyferts. The J, H and K host-galaxy col ours, however, are not typical of normal early-type galaxies; they app ear to contain significant dust and/or star formation. The sample gala xies classified as starbursts are well fitted by a single r(1/4) profi le and do not require a buried active nucleus, while most of the Seyfe rt galaxies do require an added nuclear point source to fit the light profile. J - K colour profiles and two-colour JHK diagrams reveal that the nuclei are quite red compared to the host galaxies, consistent wi th the picture of substantial centrally concentrated hot dust. Model-i ndependent parameters, such as concentration index, effective surface brightness and effective radius, are presented for the sample galaxies . No apparent correlations are found with respect to nuclear optical s pectroscopic classification. The results of this NIR study support the hypothesis that Sixty Micron Peakers represent galaxies that have rec ently undergone an interaction which has funnelled gas and dust to the central regions and resulted in a host galaxy with an elliptical-like light profile.