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Cristina Catalán-Torrecilla

Publications and source records attributed to Cristina Catalán-Torrecilla.

5 recordsLinked to original sources
arXiv2025

Revealing the baryon cycle in Galaxy Clusters: connecting galaxy dynamics and gas thermodynamics using (sub-)mm-wave and optical IFU surveys

Observations in the visible and near infrared are transforming our view of the processes affecting galaxy evolution, much of which is dominated by interactions with the large scale environment. Yet a complete picture is missing, as no corresponding high resolution view of the warm/hot intracluster, circumgalactic, and intergalactic media exists over large areas and a comparably broad range of redshifts. Combined with wide-field optical IFU surveys such as CATARSIS, a large diameter sub-mm telescope with a degree-scale field of view would enable a joint view of galaxy dynamics and gas thermodynamics, transforming our understanding of environmental processes.

astro-ph.CO↗
arXiv2018

High-resolution MEGARA IFU spectroscopy and structural analysis of a fast-rotating, disky bulge in NGC 7025

Disky bulges in spiral galaxies are commonly thought to form out of disk materials (mainly) via bar driven secular processes, they are structurally and dynamically distinct from `classical bulges' built in violent merger events. We use high-resolution GTC/MEGARA integral-field unit spectroscopic observations of the Sa galaxy NGC 7025, obtained during the MEGARA commissioning run, together with detailed 1D and 2D decompositions of this galaxy's SDSS $i$-band data to investigate the formation of its disky (bulge) component which makes up $\sim 30\%$ of the total galaxy light. With a Sérsic index $n \sim 1.80 \pm 0.24$, half-light radius $R_{\rm e} \sim 1.70 \pm 0.43$ kpc and stellar mass $M_{*} \sim (4.34 \pm 1.70) \times10^{10} M_{\odot}$, this bulge dominates the galaxy light distribution in the inner $R \sim 15"$ ($\sim 4.7$ kpc). Measuring the spins ($λ$) and ellipticities ($ε$) enclosed within nine different circular apertures with radii $R \le R_{\rm e}$, we show that the bulge, which exhibits a spin track of an outwardly rising $λ$ and $ε$, is a fast rotator for all the apertures considered. Our findings suggest that this inner disky component is a pseudo-bulge, consistent with the stellar and dust spiral patterns seen in the galaxy down to the innermost regions but in contrast to the classical bulge interpretation favored in the past. We propose that a secular process involving the tightly wound stellar spiral arms of NGC 7025 may drive gas and stars out of the disk into the inner regions of the galaxy, building up the massive pseudo-bulge.

astro-ph.GA↗
arXiv2017

Towards a new classification of galaxies: principal component analysis of CALIFA circular velocity curves

We present a galaxy classification system for 238 (E1-Sdm) CALIFA (Calar Alto Legacy Integral Field Area) galaxies based on the shapes and amplitudes of their circular velocity curves (CVCs). We infer the CVCs from the de-projected surface brightness of the galaxies, after scaling by a constant mass-to-light ratio based on stellar dynamics - solving axisymmetric Jeans equations via fitting the second velocity moment $V_{\mathrm{rms}}=\sqrt{V^2+σ^2}$ of the stellar kinematics. We use principal component analysis (PCA) applied to the CVC shapes to find characteristic features and use a $k$-means classifier to separate circular curves into classes. This objective classification method identifies four different classes, which we name slow-rising (SR), flat (FL), round-peaked (RP) and sharp-peaked (SP) circular curves. SR are typical for low-mass, late-type (Sb-Sdm), young, faint, metal-poor and disc-dominated galaxies. SP are typical for high-mass, early-type (E1-E7), old, bright, metal-rich and bulge-dominated galaxies. FL and RP appear presented by galaxies with intermediate mass, age, luminosity, metallicity, bulge-to-disk ratio and morphologies (E4-S0a, Sa-Sbc). The discrepancy mass factor, $f_d=1-M_{*}/M_{dyn}$, have the largest value for SR and SP classes ($\sim$ 74 per cent and $\sim$ 71 per cent, respectively) in contrast to the FL and RP classes (with $\sim$ 59 per cent and $\sim$ 61 per cent, respectively). Circular curve classification presents an alternative to typical morphological classification and appears more tightly linked to galaxy evolution.

astro-ph.GA↗
arXiv2014

Contribution of the disks to the SFR in the local Universe using Integral Field Spectroscopy from CALIFA

The Calar Alto Legacy Integral Field Area survey (CALIFA survey) is providing Integral Field Spectroscopy (IFS) data in the entire optical window for a diameter-limited sample of 600 objects in the Local Universe (0.005$<$z$<$0.03). One of the main goals of this survey is to explore the spatial distribution of the star formation in nearby galaxies free from the limitations associated to either UV (dust attenuation) or narrow-band H$α$ imaging (underlying H$β$ absorption). These are limitations that have prevented (until now) carrying out a detailed study of the evolution of the SFR by components (nuclei, bulges, disks), even locally. This kind of studies are key, for example, for understanding how galaxies really evolve from the Blue Cloud to the Red Sequence. We will first discuss in detail the validity of the assumption that the SFR given by the extincion-corrected H$α$ is a good measure of the total SFR by means of cross-comparing this with other SFR estimators, namely the integrated UV+22$μ$m, UV+TIR, H$α_{\rm{obs}}$+22$μ$m, or H$α_{\rm{obs}}$+TIR. Only once these effects are properly accounted for we can obtain preliminary results from the spatially-resolved analysis of the contribution of disks to the total SFR in the Local Universe, as a local benchmark for future studies of disks at high redshift. Our analysis shows that at least in the Local Universe the H$α$ luminosity derived from observations of the CALIFA IFS survey can be used to trace the SFR and that the disk to total (disk + bulge) SFR ratio is on average $\sim$88 $\%$.

astro-ph.GA↗