Multi-wavelength investigations of herschel-selected dusty star-forming galaxies

Dusty Star-Forming Galaxies (DSFGs) are found to dominate the cosmic star formation rate density at z>1 and are much more populous at z~2 than locally. Interstellar dust, as a by-product of star formation, absorbs about half of the UV and optical emission from stars and star formation and re-emit as infrared radiation. Moreover, DSFGs are likely progenitors of current-day elliptical galaxies which are commonly found in the cores of massive galaxy clusters. They are thus believed to trace massive overdensities, especially those at z>4. However, high redshift DSFGs and the environments they reside in still remain poorly understood, partially due to the lack of observations of high redshift DSFGs and their associated environments. This thesis presents a series of results which aim to better understand the nature of high redshift DSFGs and the environments they reside in. We first present 1.28GHz radio observations of three Herschel-Planck selected candidate DSFG protoclusters. With accurate positions acquired from the radio observations, we find that there are potentially z>1 overdensities aligning with two of the candidate protoclusters. We further present deep infrared observations of 13 Herschel-Planck selected candidate DSFG protoclusters. By constructing multi-wavelength photometry for sources extracted from our observations, we find that 6 of the 13 candidate DSFG protoclusters align with overdensities at 4<=z<=5, suggesting they are real DSFG protoclusters at high redshifts. We additionally investigate the nature of 19 candidate z>4 DSFGs. We find a mean redshift of =3.874+/-0.233 for our sample. Their SFR-stellar mass relation implies that either our z<3.8 500 sources are starbursts which are more intense than typical star-forming galaxies at similar redshifts, or their redshifts are underestimated. Finally, we discuss potential follow-up studies based on the work begun here, and the outlook of DSFG studies in the future.