Single CO Peak in NGC 5850

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NGC 5850 is a prototype of double-barred galaxy (Friedli et al. 1996) classified as SBb(sr) I-II (Higdon et al. 1998; Prieto et al. 1997). This kind of system is primordial to understand the physical mechanism responsible for feeding galaxy nuclei and boost the star formation rate. The CO(1-0) emission has been mapped in NGC 5850, i) in the very center, using the IRAM Plateau de Bure interferometer, to reach a 2.4×1.5(PA=-165∘) spatial resolution, and ii) in the primary bar with the IRAM-30m telescope, with a 22 beam. We have found CO emission in the center of NGC 5850, located in a single peak on the northern part of the nuclear ring. The high velocity dispersion of the molecular gas may prevent star formation in that region. Gas simulations performed with a single bar pattern and without the tidal influence of the companion NGC 5846 are unable to reproduce the features observed in NGC 5850 (Combes, Leon, Friedli & Buta 1998, in preparation). The decoupling of a second bar appears necessary. The presence of the single molecular peak could be due to an m=1 mode excited by the massive companion.