Related papers: Unsupervised classification reveals new evolutiona…
The GOODS-North field centered around the historical Hubble Deep Field-North provides one of the richest multiwavelength datasets compiled, spanning radio to X-ray frequencies, for studying the formation and evolution of galaxies at high…
Observations of high-redshift galaxies provide a critical direct test to the theories of early galaxy formation, yet to date, only three have been spectroscopically confirmed at $z>12$. Due to strong gravitational lensing over a wide area,…
The availability of high-quality spectra for a large number of galaxies in the SDSS survey allows for a more sophisticated extraction of information about their stellar populations than, e.g., the luminosity weighted age. Indeed,…
Classification of intermediate redshift ($z$ = 0.3--0.8) emission line galaxies as star-forming galaxies, composite galaxies, active galactic nuclei (AGN), or low-ionization nuclear emission regions (LINERs) using optical spectra alone was…
Investigating the assembly history of the most massive and passive galaxies will enhance our understanding of why galaxies exhibit such a remarkable diversity in structure and morphology. In this paper, we simultaneously investigate the…
Distinguishing active galaxies from star-forming galaxies is essential for understanding galaxy evolution. Diagnostic methods like the BPT (Baldwin, Phillips, and Terlevich) diagram use optical emission-line ratios to separate galaxies.…
The observable characteristics and subsequent evolution of young stellar populations is dominated by their massive stars. As our understanding of those massive stars and the factors affecting their evolution improves, so our interpretation…
We trace the evolution and the star formation history of passive galaxies, using a subset of the VIMOS Public Extragalactic Redshift Survey (VIPERS). We extracted from the VIPERS survey a sample of passive galaxies in the redshift range…
We study the quenching of galaxies in different environments and its evolution in the redshift range $0.43 \leq z \leq 0.89$. For this purpose, we identify galaxies inhabiting filaments, the isotropic infall region of groups, the field, and…
Numerous methods for finding clusters at moderate to high redshifts have been proposed in recent years, at wavelengths ranging from radio to X-rays. In this paper we describe a new method for detecting clusters in two-band optical/near-IR…
We first present a catalogue of photometric redshifts for 14.68 million galaxies derived from the 7-band photometric data of Hyper Suprime-Cam Subaru Strategic Program and the Wide-field Infrared Survey Explorer using the nearest-neighbour…
Galaxy morphology offers significant insights into the evolutionary pathways and underlying physics of galaxies. As astronomical data grows with surveys such as Euclid and Vera C. Rubin , there is a need for tools to classify and analyze…
Using photometric data from the Dark Energy Survey and the Wide-field Infrared Survey Explorer, we estimate photometric redshifts for 105 million galaxies using the nearest-neighbour algorithm. From such a large data base, 151,244 clusters…
We present further spectroscopic observations for a sample of galaxies selected in the vacuum ultraviolet (UV) at 2000 \AA from the FOCA balloon-borne imaging camera of Milliard et al. (1992). This work represents an extension of the…
Galaxies undergoing formation and evolution can now be observed over a time baseline of some 12 Gyr. An inherent difficulty with high-redshift observations is that the objects are very faint and the best resolution (HST) is only ~0.5 kpc.…
The DEEP2 Galaxy Redshift Survey is now well underway, having already measured the redshifts to ~5600 galaxies in its first season of observations. Here I briefly review the survey itself, before discussing in more detail some of the…
A critical issue in studying the evolution of galaxy clusters is to find ways that enable meaningful comparisons of clusters observed at different redshifts, as well as in various stages of their growth. Studies in the past have typically…
We exploit the first public data release of VIPERS to investigate environmental effects in galaxy evolution between $z\sim0.5$ and $0.9$. The large number of spectroscopic redshifts over an area of about $10\,\mathrm{deg}^2$ provides a…
We use the Random Forest (RF) algorithm to develop a tool for automated activity classification of galaxies into 5 different classes: Star-forming (SF), AGN, LINER, Composite, and Passive. We train the algorithm on a combination of mid-IR…
We examine the effectiveness of identifying distinct evolutionary histories in IllustrisTNG-100 galaxies using unsupervised machine learning with Gaussian Mixture Models. We focus on how clustering compressed metallicity histories and star…