arXiv subjects

B. Rodriguez

Publications and source records attributed to B. Rodriguez.

6 recordsLinked to original sources

arXiv2025

The EDGE-CALIFA Survey: An integral field unit-based integrated molecular gas database for galaxy evolution studies in the Local Universe

Studying galaxy evolution requires knowledge not only of the stellar properties, but also of the interstellar medium (in particular the molecular phase) out of which stars form, using a statistically significant and unbiased sample of galaxies. To this end, we introduce here the integrated Extragalactic Database for Galaxy Evolution (iEDGE), a collection of integrated stellar and nebular emission lines, and molecular gas properties from 643 galaxies in the local Universe. These galaxies are drawn from the CALIFA datasets, and are followed up in CO lines by the APEX, CARMA, and ACA telescopes. As this database is assembled from data coming from a heterogeneous set of telescopes (including IFU optical data and single-dish and interferometric CO data), we adopted a series of techniques (tapering, spatial and spectral smoothing, and aperture correction) to homogenise the data. Due to the application of these techniques, the database contains measurements from the inner regions of the galaxies and for the full galaxy extent. We used the database to study the fundamental star formation relationships between star formation rate (SFR), stellar mass ($M_*$), and molecular gas mass ($M_{\rm mol}$) across galaxies with different morphologies. We observed that the diagrams defined by these quantities are bi-modal, with early-type passive objects well separated from spiral star-forming galaxies. Additionally, while the molecular gas fraction ($f_{\rm mol}=M_{\rm mol}/M_*$) decreases homogeneously across these two types of galaxies, the star formation efficiency (SFE=SFR/$M_{\rm mol}$) in the inner regions of passive galaxies is almost two orders of magnitude lower compared to the global values. This indicates that inside-out quenching requires not only low $f_{\rm mol}$, but also strongly reduced SFE in the galactic centres.

astro-ph.GA↗

arXiv2025

The EDGE-CALIFA survey: Star formation relationships for galaxies at different stages of their evolution

Galaxy evolution is largely driven by star formation activity or by the cessation of it, also called star formation quenching. In this paper, we present star formation scaling relations for galaxies at different evolutionary stages. To do so, we used the integrated Extragalactic Database for Galaxy Evolution (iEDGE), which collects CO, optical continuum, and emission line information for 643 galaxies from the CALIFA IFU dataset. By considering the patterns described by star-forming and retired regions, we grouped the galaxies into quenching stages using the emission line classification scheme, QueStNA. We observed that the molecular gas mass ($M_{\rm mol}$) decreases from star-forming to retired systems and so does the molecular-to-stellar mass ratio ($f_{\rm mol}$). In contrast, star formation efficiency (SFE) is constant in the quenching stages dominated by star formation and rapidly declines afterwards. We observed that this rapid decline is more pronounced in the centre of the galaxies compared to the rest of the discs, reflecting the inside-out quenching displayed by nearby galaxies. We noticed that the relations between $M_{\rm mol}$ and the stellar mass ($M_*$) become increasingly shallow with the quenching stages; however, the relations between the star formation rate (SFR) and $M_{\rm mol}$ steepen when going from star-forming to retired systems. We observed that a three-dimensional relation between SFR, $M_*$, and $M_{\rm mol}$ exists for star-forming galaxies, while data points from other quenching groups are scattered across the parameter space. Taken together, these pieces of evidence indicate that the quenching of the galaxies cannot be explained solely by a depletion of the molecular gas and that a significant decrease in the SFE is necessary to retire the centre of the galaxies beyond the star formation green valley.

astro-ph.GA↗

arXiv2023

Young Stellar Object Candidates in IC 417

IC 417 is in the Galactic Plane, and likely part of the Aur OB2 association; it is ~2 kpc away. Stock 8 is one of the densest cluster constituents; off of it to the East, there is a 'Nebulous Stream' (NS) that is dramatic in the infrared (IR). We have assembled a list of literature-identified young stellar objects (YSOs), new candidate YSOs from the NS, and new candidate YSOs from IR excesses. We vetted this list via inspection of the images, spectral energy distributions (SEDs), and color-color/color-magnitude diagrams. We placed the 710 surviving YSOs and candidate YSOs in ranked bins, nearly two-thirds of which have more than 20 points defining their SEDs. The lowest-ranked bins include stars that are confused, or likely carbon stars. There are 503 in the higher-ranked bins; half are SED Class III, and $\sim$40\% are SED Class II. Our results agree with the literature in that we find that the NS and Stock 8 are at about the same distance as each other (and as the rest of the YSOs), and that the NS is the youngest region, with Stock 8 a little older. We do not find any evidence for an age spread within the NS, consistent with the idea that the star formation trigger came from the north. We do not find that the other literature-identified clusters here are as young as either the NS or Stock 8; at best they are older than Stock 8, and they may not all be legitimate clusters.

astro-ph.SR↗

arXiv2015

Estudio Te\'orico del espectro de emisi\'on para un sistema microcavidad-punto cu\'antico en una aproximaci\'on de campo medio (Theoretical study of emission spectrum for a quantum dot-microcavity system in a mean field approximation)

En este trabajo, se obtiene una expresi\'on num\'erica para calcular el espectro de emisi\'on de un sistema microcavidad-punto cu\'antico usando una teor\'ia de campo medio en el formalismo de la matriz densidad. El sistema modelado es un micropilar semiconductor que contiene un \'unico punto cu\'antico en el interior de la microcavidad, este sistema presenta p\'erdida de fotones a trav\'es de los espejos de la cavidad y bombeo de excitones al punto cu\'antico. Obtenemos una ecuaci\'on maestra de campo medio no lineal que nos permite calcular el espectro de emisi\'on. In this work, we deduce a numerical expression to calculate the emission spectrum for a quantum dot-microcavity system, using a mean field theory in the density matrix formalism. The open system modeled, is a typical semiconductor micropillar that contains a single quantum dot inside a microcavity, this system presents leakage of photons through cavity mirrors and pumping of excitons to the quantum dot. We obtain a mean field nonlinear master equation that allow us calculate the emission spectrum.

cond-mat.mes-hall↗

arXiv2007

The Solar Wind Around Pluto (SWAP) Instrument Aboard New Horizons

The Solar Wind Around Pluto (SWAP) instrument on New Horizons will measure the interaction between the solar wind and ions created by atmospheric loss from Pluto. These measurements provide a characterization of the total loss rate and allow us to examine the complex plasma interactions at Pluto for the first time. Constrained to fit within minimal resources, SWAP is optimized to make plasma-ion measurements at all rotation angles as the New Horizons spacecraft scans to image Pluto and Charon during the flyby. In order to meet these unique requirements, we combined a cylindrically symmetric retarding potential analyzer (RPA) with small deflectors, a top-hat analyzer, and a redundant/coincidence detection scheme. This configuration allows for highly sensitive measurements and a controllable energy passband at all scan angles of the spacecraft.

astro-ph↗

arXiv2005

A self-similar dynamics in viscous spheres

We study the evolution of radiating and viscous fluid spheres assuming an additional homothetic symmetry on the spherically simmetric space--time. We match a very simple solution to the symmetry equations with the exterior one (Vaidya). We then obtain a system of two ordinary differential equations which rule the dynamics, and find a self--similar collapse which is shear--free and with a barotropic equation of state. Considering a huge set of initial self--similar dynamics states, we work out a model with an acceptable physical behavior.

gr-qc↗