High Spatial Resolution KAO Far-Infrared Observations of the Central   Regions of Infrared-Bright Galaxies
  We present new high spatial resolution Kuiper Airborne Observatory 50 micron and/or 100 micron data for 11 infrared-bright galaxies. We also tabulate previously published KAO data for 11 other galaxies, along with the IRAS data for the bulges of M 31 and M 81. We find that L(FIR)/L(B) and L(FIR)/L(H) correlate with CO (1 - 0) intensity and tau(100). Galaxies with optical or near-infrared signatures of OB stars in their central regions have higher values of I(CO) and tau(100), as well as higher far-infrared surface brightnesses and L(FIR)/L(B) and L(FIR)/L(H) ratios. L(FIR)/L(H(alpha)) does not correlate strongly with CO and tau(100). These results support a scenario in which OB stars dominate dust heating in the more active galaxies and older stars are important in quiescent bulges. 
Beverly J. Smith and P. M. Harvey (University of Texas)