LIGHT PROFILES AND PATTERN SPEEDS FOR BARS IN EARLY-TYPE AND LATE-TYPE GALAXIES

J, H, and K infrared band observations of 11 barred galaxies, and B an d I band observations of 8 barred galaxies, spanning a wide range of H ubble types, confirm the trend found earlier that early types tend to have flat light profiles along the bars and late types have exponentia l light profiles. Both types have nearly continuous exponential light profiles when azimuthally averaged. The flat profiles arise from exces s old and young stars at the bar ends, presumably where the orbits cro wd together near the inner 4:1 resonance. The exponential profiles hav e no such crowding and also lack offset leading dustlanes as if there is no inner Lindblad resonance inside the bar. Arm/interarm contrasts in J band increase with radius near the center and then become constan t or decrease with radius at a value of arm/interarm similar to 6. Thi s saturation of wave amplitude tends to occur at the same radius where the arms bifurcate or become multiple, suggesting that spiral waves l imit their own amplitudes at large radii by coupling to higher order m odes. A compilation of bar pattern speeds from the literature, mostly covering early types, generally puts corotation at a distance between 1.2 and 1.4 times the bar semi-major axis length, usually in the middl e of the strong part of the spiral arms. These observations imply that early-type bars end because of orbit resonance scattering slightly be yond their inner 4:1 resonances; the spirals and rings in these galaxi es appear to coarctate with the bars. Patterns speeds in late type bar s remain unknown. (C) 1996 American Astronomical Society.