Related papers: Looking for the First Galaxies with EMIR/GTC
The spectral absorption lines in early-type galaxies contain a wealth of information regarding the detailed abundance pattern, star formation history, and stellar initial mass function (IMF) of the underlying stellar population. Using our…
Identifying stars formed in pristine environments (Pop III) within the first billion years is vital to uncovering the earliest growth and chemical evolution of galaxies. Pop III galaxies, however, are typically expected to be too faint and…
We have developed a new stellar population synthesis model designed to study early-type galaxies. It provides optical and near-infrared colors, and line indices for 25 absorption lines. It can synthesize single age, single metallicity…
Observing the first generation of Population III (Pop III) stars is one of the most demanding challenges in astronomy. Indeed, Pop III stars are expected to predominantly form within faint minihalos at early times with a top-heavy initial…
We present low resolution Spitzer-IRS spectra of 40 ETGs, selected from a sample of 65 ETGs showing emission lines in their optical spectra. We homogeneously extract the mid-infrared (MIR) spectra, and after the proper subtraction of a…
The determination of chemical composition is crucial for investigating the formation and evolution of star forming galaxies and provides a powerful tool to constrain the effects of galactic winds and accretion from the cosmic web. In this…
Population III stars, the first generation of stars formed from primordial Big Bang material with a top-heavy IMF, should contribute substantially to the Universe reionization and they are crucial for understanding the early metal…
Massive Pop III stars can die as energetic supernovae that enrich the early universe with metals and determine the properties of the first galaxies. With masses of about $10^9$ Msun at $z \gtrsim 10$, these galaxies are believed to be the…
It has frequently been suggested that the stellar IMF in galaxies was top-heavy at early times. This would be plausible physically if the IMF depends on a mass scale such as the Jeans mass that was higher at earlier times because of the…
The first stars hold intrinsic interest for their uniqueness and for their potential importance to galaxy formation, chemical enrichment, and feedback on the intergalactic medium (IGM). The metal-free composition of the first stars…
We investigate the transition from primordial Population III (Pop III) star formation to normal Pop II star formation in the first galaxies using new cosmological hydrodynamic simulations. We find that while the first stars seed their host…
The properties of the first galaxies are shaped in large part by the first generations of stars, which emit high energy radiation and unleash both large amounts of mechanical energy and the first heavy elements when they explode as…
An essential component of galaxy formation theory is the stellar initial mass function (IMF), that describes the parent distribution of stellar mass in star forming regions. We present observational evidence in a sample of early-type…
(shortened) We have obtained blue integrated spectra of 175 nearby early-type galaxies, covering a wide range in galaxy velocity dispersion, and emphasizing those with sigma < 100 km/s. Galaxies have been observed both in the Virgo cluster…
We summarize the principles and fundamental ingredients of evolutionary synthesis models, which are stellar evolution, stellar atmospheres, the IMF, star-formation histories, nebular emission, and also attenuation from the ISM and IGM. The…
Using three-dimensional cosmological simulations, we study the assembly process of one of the first galaxies, with a total mass of 10^8 M_sun, collapsing at z = 10. Our main goal is to trace the transport of the heavy chemical elements…
A spectrophotometric model able to compute the integrated spectrum of a galaxy, including the contribution both of the stellar populations and of the ionized interstellar gas of the HII regions powered by young hot stars, has been used to…
We conduct a comprehensive investigation of the detectability of the first stars and their enrichment signatures in galaxy clusters. We show that the mean metallicity of outflows from objects containing these Population III (PopIII) stars…
Population III (or Pop. III) stars, the first stellar generation built up from metal-free primordial gas, first started to form at redshifts z ~ 30. They formed primarily in small dark matter halos with masses of a few million solar masses.…
The detection of Pop III supernovae could directly probe the primordial IMF for the first time, unveiling the properties of the first galaxies, early chemical enrichment and reionization, and the seeds of supermassive black holes. Growing…