Related papers: Recalibration of [O II] $\lambda 3727$ as a Star F…

We present a simple metallicity estimator based on the logarithmic [NII]6584 / Halpha ratio, hereafter N2, which we envisage will become very useful for ranking galaxies in a metallicity sequence from redshift survey quality data even for…

We present the first results of a project, LSD, aimed at obtaining spatially-resolved, near-infrared spectroscopy of a complete sample of Lyman-Break Galaxies at z~3. Deep observations with adaptive optics resulted in the detection of the…

In the redshift interval of $2<z<3$, the physical conditions of the inter-stellar medium (ISM) in star-forming galaxies are likely to be different from those in the local Universe because of lower gaseous metallicities, higher gas…

[abridged] Using stacked Sloan Digital Sky Survey spectra, we present the detection of [OII]3727,3730 nebular emission from galaxies hosting CaII and MgII absorption line systems. Both samples of absorbers, 345 CaII systems and 3461 MgII…

Our goal is to study the existing star formation rate calibrations based on emission-line luminosities and to provide new ones. We use the SDSS data release DR4, which gives star formation rates and emission-line luminosities of more than…

We report on the discovery of 28 $z\approx0.8$ metal-poor galaxies in DEEP2. These galaxies were selected for their detection of the weak [OIII]$\lambda$4363 emission line, which provides a "direct" measure of the gas-phase metallicity. A…

What main mechanisms set the star formation rate (SFR) of galaxies? This PhD thesis is a quest into the influences of gas and active galactic nuclei (AGNs) on the SFR, with particular focus on massive galaxies at z~2. First, a new code if…

We use the large spectroscopic dataset of the MOSFIRE Deep Evolution Field (MOSDEF) survey to investigate some of the key factors responsible for the elevated ionization parameters (U) inferred for high-redshift galaxies, focusing in…

Using the sample from the \it Redshift One LDSS3 Emission line Survey \rm (ROLES), we probe the dependence of star formation rate (SFR) and specific star formation rate (sSFR) as a function of stellar mass $M_*$ and environment as defined…

Based on O II recombination lines we present a new calibration (called O II[RL]) of Pagel's O23 indicator to determine the O/H abundance ratio in extragalactic H II regions and emission line galaxies. The O II(RL) calibration produces O/H…

About 45% of the point sources detected in the 2 Ms Chandra exposure of the HDF-N can be matched with moderately bright galaxies with z<1.4 that have been studied by the Caltech Faint Galaxy Redshift Survey. Although the optical spectra of…

[Abridged] We compare H-alpha, ultraviolet (UV) and infrared (IR) indicators of star formation rate (SFR) for a sample of z = 0.84 galaxies from the High-z Emission Line Survey (HiZELS). Using multi-wavelength diagnostics, we estimate that…

The influence of Active Galactic Nuclei (AGN) on star formation within their host galaxies remains a topic of intense debate. One of the primary challenges in quantifying the star formation rate (SFR) within AGN hosts arises from the…

We have used extensive libraries of model and empirical galaxy spectra (assembled respectively from the population synthesis code of Bruzual and Charlot and the fourth data release of the Sloan Digital Sky Survey) to interpret some puzzling…

With the goal of investigating the degree to which the mid-infrared emission traces the star formation rate (SFR), we analyze Spitzer 8 um and 24 um data of star-forming regions in a sample of 33 nearby galaxies with available HST/NICMOS…

The [CII] 157.74 \mu m line is an important coolant for the neutral interstellar gas. Since [CII] is the brightest spectral line for most galaxies, it is a potentially powerful tracer of star formation activity. In this paper we present a…

Using H-alpha spectra of 114 rest-frame UV-selected galaxies at z~2, we compare inferred star formation rates (SFRs) with those determined from the UV continuum luminosity. After correcting for extinction using standard techniques based on…

The H-alpha (Ha) emission line in galaxies is a powerful tracer of their recent star formation activity. With the advent of JWST, we are now able to routinely observe Ha in galaxies at high redshift (z > 3) and thus measure their star…

We present, for the first time, a statistical study of [N II] 205 mciron line emission for a large sample of local luminous infrared galaxies using Herschel Spectral and Photometric Imaging Receiver Fourier Transform Spectrometer (SPIRE…

The star formation rate density (SFRD) is an important tool in galaxy evolution that allows us to identify at which cosmic time galaxies are more efficient at forming stars. For low-mass star-forming galaxies, the SFRD as a function of…