| Description |
We propose Herschel/SPIRE photometric observations of dust continuum emission in a sample of 19 weak line quasars (WLQs) at 2<z<5. These objects have weak or undetectable UV emission lines, with typical rest-frame Lya +N V equivalent widths <15 A. However, their broad band AGN continuum emission from is similar to that of normal radio-quiet/intermediate quasars, indicating that the weak UV line features are unlikely to be due to a relativistically boosted continuum. It is possible that these WLQs are young AGN systems, in which the emission line regions associated with high ionization lines have not yet fully formed. In this proposal, we request a systematic survey of the rest-frame far-infrared (FIR) dust continuum emission with SPIRE at 250 um, 350 um, and 500 um. The FIR emission from 30 to 60 K warm dust provides the most reliable estimates of star formation rates in the quasars/galaxies at high redshifts. Our goals are i) to determine the dust temperature, dust mass, and FIR luminosity of each object by fitting the SPIRE flux densities to an optically thin graybody model and constrain the star formation rates in these WLQs and ii) to obtain the mean FIR emission of the WLQs and understand how it compares to the normal/strong emission line quasars. The observations will be a crucial test of the hypothesis that if these WLQs are at a young evolutionary phase, in which the central AGN activity has just turned on and intense star formation is ongoing in the quasar hosts. |
