The Dusty Young Universe - Star formation in high-redshift Quasars

点击翻译按钮获取中文摘要

The detections of thermal dust emission at (sub-)mm wavelengths in a significant fraction of the highest redshift quasars (z >5) imply that large amounts of dust must have been synthesized already during the first billion years after the Big Bang. Observations at 24 μm with Spitzer have also shown that very hot dust is present close to the QSO core in most high redshift quasars. However, even combined these observations only catch the tails of the dust emission at λrest >100 μm and λrest <5 μm, respectively. In order to measure the peak of the dust emission at λrest ~10−100 μm, sensitive far-infrared (FIR) observations are needed. This is paramount for a concise picture of the dust properties in high redshift QSOs and the incidence of vigorous star-formation in early AGN host galaxies, which may have immense impact on our understanding of galaxy evolution and the origin of the interplay between black hole masses and galaxy bulges. Our Herschel Key Program currently collects such FIR photometry for 71 quasars at z >5. We here ask for funding for one post-doctoral research position to lead the analysis, publication, and distribution of the project data. The proposed funding would enable the comprehensive analysis of a complete set of spectral energy distributions (SEDs) covering the rest frame UV through infrared regime. Multi-component fitting and modeling of the SEDs will provide bolometric luminosities, dust masses and star-formation rates for a statistically significant sample of quasars in the early universe.