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NGC 1144, the eastern component of an interacting galaxy system Arp 118 which has an elliptical companion --- NGC 1143, has a distorted disk and an extended ringlike structure of HII regions. Using the IRAM 30-m telescope, we have detected extremely strong and wide CO emission line (FWZI $\sim 1100 \ km s^{-1}$) from the nuclei of NGC 1144 which itself is an interacting, infrared-luminous, ring-like Seyfert II. The extended ring structure, $\sim 10 \ kpc$ from the nuclei also shows very strong CO emission. The total molecular mass is $M_{H_2} \sim 4 \times 10^{10} \ M_{\odot}$, exceeds that of Arp 220 and is one of the highest in the local universe. About $1 \times 10^{10}$ ms molecular gas is contained in the ``ring'' $\sim 10 \ kpc$ from the nuclear region. Although the galaxy has a huge molecular mass, the OB star formation efficiency, indicated by the ratio of $L_{IR}/M_{H_2}$ $\sim 5$ , is comparable to the Milky Way and is one of the lowest observed for any interacting IR-luminous galaxy.
Arp 118 (in particular NGC 1144) is one of the most fascinating merging systems yet observed. It clearly has huge quantities of molecular gas and may be a merger at an early stage with a strong Extranuclear starburst, but a very low massive star formation efficiency. Our future interferometry of the CO(1-0) line will provide the best opportunity to study the distribution and kinematics of the molecular gas in this spectacular merging/interacting galaxy system.
