We investigate the properties of galaxies as they shut off star formation over the 4 billion years surrounding peak cosmic star formation. To do this, we categorize ∼7000 galaxies from 1 < z < 4 into 90 groups based on the shape of their spectral energy distributions (SEDs) and build composite SEDs with R ∼ […]
Studies show the rate of quenching and the quiescent galaxy fraction are correlated with both increasing stellar mass and local environment. In the local Universe, these effects may be separable but in the more distant Universe, the evidence suggests otherwise. With ZFOURGE we studied the effects of galaxy environment on the evolution of the stellar–mass […]
We investigate the SMBH-galaxy connection by tracking the mean black hole accretion rate (BHAR) and mean star formation rate (SFR) of a sample of galaxies out to z = 2:5. We perform X-ray stacking and SED decomposition to estimate BHARs and SFRs. While such studies are prevalent, they are often limited to AGN-selected or mass-limited […]
In the low redshift Universe (z ~ 0.1), it has been shown that the respective relationships between stellar mass and environment on quenching are largely separable, implying there are two distinct quenching processes at work: one that correlates with stellar mass (independent of environment) and one that correlates with galaxy environment (independent of stellar mass). […]
10We construct a set of composite spectral energy distributions (SEDs) from ZFOURGE galaxies in 2.5<z<4.0 and SNR<20 (and removing those with evidence of active galactic nuclei). Included are two composite SEDs comprised of galaxies with particularly strong nebular emission features. The SEDs of these galaxies are consistent with young, blue, vigorously star-forming galaxies, analogous to […]
For the first time, we trace the size evolution of a complete sample of star-forming galaxies to z ∼ 7 and confirm that the mass−size relation exists at this redshift. We obtain average sizes in redshift bins by fitting the mass–size relation and by measuring the half-light radius from image stacks. The sizes of star- […]
Straatman et al. 2016 Summary: The FourStar galaxy evolution survey (ZFOURGE) is a 45 night legacy program with the FourStar near-infrared camera on Magellan and one of the most sensitive surveys to date. ZFOURGE covers a total of 400 arcmin2 in cosmic fields CDFS, COSMOS and UDS, overlapping CANDELS. The redshift range 1 < z […]
We build a set of composite galaxy spectral energy distributions (SEDs) by de-redshifting and scaling multi-wavelength photometry from a mass-selected sample of ~4000 galaxies in the ZFOURGE survey. After adding far infrared data from Spitzer and Herschel, we test the efficacy of the UVJ diagram at 1 Blue star-forming galaxies show IRX and β values […]
Cowley et al. 2015 Summary: We investigate AGN candidates within the FourStar Galaxy Evolution (ZFOURGE) Survey to determine the impact they have on star formation in their host galaxies. By cross- matching the deep Ks-band imaging of ZFOURGE with overlapping multi wavelength data, we identify a population of radio, X-ray, and infrared-selected AGN over z […]
Powerful radio jets emitted from Active Galactic Nuclei (AGN) are commonly held as one of the primary methods by which star-formation may be suppressed in massive galaxies. Despite this there is much discussion around the overall effect that radio-AGN have on their host galaxies in practise, with some evidence to suggest that these objects not […]