ISO 5 - 200 micron photometry of ULIRGs and PG quasars
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        Martin Haas, Max-Planck-Institut f. Astronomie, 
                     Heidelberg, Germany
   
   
    Is every PG quasar accompanied by considerable amounts of dust?
    Or do also relatively dust-free, naked quasars exist which 
    might be more evolved? Is the AGN the sole power source 
    in dusty PG quasars or do starbursts play a significant role?
   
    What is the relation between PG quasars and ultraluminous IR galaxies?
    What are the edge-on counterparts of dusty PG quasars?
    Why could also ULIRGs with cool MIR/FIR colors house a PG quasar?
    Do ULIRGs have very cold dust (T = 15 K) like normal spirals?
   
    Topics like those above are addressed on the basis of sensitive near- 
    to far-infrared photometry with the Infrared Space Observatory ISO.