arXiv subjects

Emmanuel Ríos-López

Publications and source records attributed to Emmanuel Ríos-López.

4 recordsLinked to original sources

arXiv2026

ELLIPSECT: A surface brightness analysis tool for GALFIT 3

EllipSect is a user-friendly analysis and measurement tool, implemented in Python, that operates on the imaging data together with the output of the widely used 2D surface-brightness fitting code GALFIT 3. It produces publication-quality figures and exportable data products to enable quantitative assessment of GALFIT 3 models and their individual components. In addition, EllipSect computes non-parametric measurements that are not provided by GALFIT 3, including the total effective radius resulting from multi-component fits, cusp radius, and the Petrosian radius. This paper provides examples and a quick guide for EllipSect.

astro-ph.IM↗

arXiv2025

2D Surface Brightness Modelling of Large 2MASS Galaxies II: The Role of Classical Bulges and Pseudobulges on Galaxy Scaling Relations and its implication for Supermassive Black Hole Formation

We have generated 2D-multicomponent surface brightness (SB) modelling for 100 galaxies in the Large Galaxy Atlas (LGA) together with 19 nearby cD galaxies using the near-infrared (NIR) images from 2MASS (J, H and Ks ). Our final sample of 119 galaxies includes cD galaxies, Virgo cluster galaxies, group galaxies, and field galaxies. We revisited known scaling relations (SRs) involving structural parameters, as well as those involving supermassive black holes (SMBHs) and ultramassive black holes (UMBHs). Refining the SRs, we also revisited the bulge classification and considered the Fundamental Plane (FP) and its projections, as well as other SRs, such as the colour-magnitude relation (CMR), Tully-Fisher relation (TFR) and luminosity concentration relation (LCR). Classical bulges follow the same relations as elliptical galaxies, while pseudobulges are usually outliers. The NIR colours of classical bulges and pseudobulges indicate that their ages are not radically different despite their spread in luminosity, but we noticed that classical bulges are more luminous than pseudobulges, therefore, this property provides a complementary bulge classification criterion. We included pseudobulges from other studies to strengthen the tendencies seen for pseudobulges in our sample. From the SRs for BHs, we found that pseudobulges do not follow SRs for early-type galaxies and classical bulges. Additionally, the lack of correlation between BHs and discs may indicate these structures have not coevolved. From the revision of SRs, we present a sample of galaxies likely to host SMBHs or UMBHs, which are suitable for dynamical BH mass determination from the ground.

astro-ph.GA↗

arXiv2021

2D Surface Brightness Modelling of Large 2MASS Galaxies I: Photometry and Structural Parameters

We have studied a sample of 101 bright 2MASS galaxies from the Large Galaxy Atlas (LGA), whose morphologies span from early to late-types. We have generated estimates for structural parameters through a two-dimensional (2D) surface brightness photometric decomposition in the three 2MASS bands (J, H, Ks). This work represents a detailed multi-component photometric study of nearby galaxies. We report total magnitudes, effective radii, concentration indices, among other parameters, in the three 2MASS bands. We found that the integrated total magnitudes of early-type galaxies (ETGs) measured on 2MASS LGA mosaics are ~0.35 mag dimmer, when compared with images generated from IRSA image tiles service; nevertheless, when comparing late-type galaxies (LTGs) we did not find any difference. Therefore, for ETGs we present the results derived on IRSA image tiles, while for LTGs we used data from the LGA mosaics. Additionally, by combining these structural parameters with scaling relations and kinematic data, we separated classical bulges from pseudobulges. We found that ~40 % of the objects in our sample are classified as pseudobulges, which are found preferentially in LTGs. Also, our findings confirm trends reported earlier in the distributions for some physical parameters, such as Sérsic index, B/T and q ratios. In general, our results are in agreement with previous one-dimensional studies. In a companion paper, we revise some of the scaling relations among global galaxy properties, as well as their interrelation with Supermassive Black Holes.

astro-ph.GA↗

arXiv2019

TOROS Optical follow-up of the Advanced LIGO-VIRGO O2 second observational campaign

We present the results of the optical follow-up, conducted by the TOROS collaboration, of gravitational wave events detected during the Advanced LIGO-Virgo second observing run (Nov 2016 -- Aug 2017). Given the limited field of view ($\sim100\arcmin$) of our observational instrumentation we targeted galaxies within the area of high localization probability that were observable from our sites. We analyzed the observations using difference imaging, followed by a Random Forest algorithm to discriminate between real and bogus transients. For all three events that we respond to, except GW170817, we did not find any bona fide optical transient that was plausibly linked with the observed gravitational wave event. Our observations were conducted using telescopes at Estación Astrof\'ısica de Bosque Alegre, Cerro Tololo Inter-American Observatory, and the Dr. Cristina V. Torres Memorial Astronomical Observatory. Our results are consistent with the LIGO-Virgo detections of a binary black hole merger (GW170104) for which no electromagnetic counterparts were expected, as well as a binary neutron star merger (GW170817) for which an optical transient was found as expected.

astro-ph.HE↗