CO distribution and kinematics along the bar in the strongly barred spiralNGC 7479

We report on the 2 ".5 (400 pc) resolution CO (J = 1 --> 0) observations co vering the whole length of the bar in the strongly barred late-type spiral galaxy NGC 7479. CO emission is detected only along a dust lane that traver ses the whole length of the bar, including the nucleus. The emission is str ongest in the nucleus. The distribution of emission is clumpy along the bar outside the nucleus and consists of gas complexes that are unlikely to be gravitationally bound. The CO kinematics within the bar consist of two sepa rate components. A kinematically distinct circumnuclear disk, <500 pc in di ameter, is undergoing predominantly circular motion with a maximum rotation al velocity of 245 km s(-1) at a radius of 1 " (160 pc). The GO-emitting ga s in the bar outside the circumnuclear disk has substantial noncircular mot ions that are consistent with a large radial velocity component, directed i nward. The CO emission has a large velocity gradient across the bar dust la ne, ranging from 0.5 to 1.9 km s(-1) pc(-1) after correcting for inclinatio n, and the projected velocity change across the dust lane is as high as 200 km s(-1). This sharp velocity gradient is consistent with a shock front at the location of the bar dust lane. A comparison of Hu and CO kinematics ac ross the dust lane shows that, although the Ha emission is often observed b oth upstream and downstream from the dust lane, the CO emission is observed only where the velocity gradient is large. We also compare the observation s with hydrodynamic models and discuss star formation along the bar.