M. Angeles Gomez-Flechoso

@ucm.es

Dept. Earth Science and Astrophysics / Faculty of Physics / Universidad Complutense de Madrid

M. Angeles Gomez-Flechoso


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https://researchid.co/magflechoso

RESEARCH, TEACHING, or OTHER INTERESTS

Astronomy and Astrophysics, Physics and Astronomy
45

Scopus Publications

Scopus Publications

  • Does mentoring frequency matter? Effects on dropout rates and average grades among university students
    Miguel A. Alonso García, Aitana González Ortiz de Zárate, Irene Aliagas, Ma Ángeles Gómez-Flechoso
    Evaluation and Program Planning, 2026
  • Peer mentoring, university dropout and academic performance before, during, and after the pandemic in Spain
    Aitana González-Ortiz-de-Zárate, Miguel Aurelio Alonso-García, María de los Ángeles Gómez-Flechoso, Irene Aliagas
    Evaluation and Program Planning, 2025
  • Stellar tidal streams around nearby spiral galaxies with deep imaging from amateur telescopes
    David Martínez-Delgado, Michael Stein, Joanna D. Sakowska, M. Maurice Weigelt, Javier Román, et al.
    Astronomy and Astrophysics, 2025
    Context. Tidal interactions between massive galaxies and their satellites are fundamental processes in a universe with a Λ cold dark matter (ΛCDM) cosmology, and they redistribute material into faint features that preserve records of past galactic interactions. While stellar streams in the Local Group impressively demonstrate satellite disruption, they do not constitute a statistically significant sample. Constructing a substantial catalog of stellar streams beyond the Local Group remains challenging due to the difficulties in obtaining sufficiently deep wide-field images of galaxies. Despite their potential to illuminate dark matter distribution and galaxy formation processes overall, stellar streams remain underutilized as cosmological probes. Aims. The Stellar Tidal Stream Survey (STSS) addresses this observational gap by leveraging amateur telescopes to obtain deep scientific-grade images of galactic outskirts capable of building a more statistically meaningful sample of stellar streams. Methods. Over the past decade, the STSS has acquired deep (up to surface brightness limit ∼28.3 mag/arcsec2 in the r-band) wide-field images of 16 nearby Milky Way analog galaxies using a coordinated network of robotic amateur telescopes, which enabled the survey to avoid the issues associated with “mosaicking” smaller images taken with a single professional telescope. Results. Our survey revealed a diverse range of previously unreported faint features related to dwarf satellite accretion, including stellar streams, shells, and umbrella-like structures. We serendipitously discovered an ultra-diffuse galaxy (NGC150-UDG1) that shows hints of tidal tails. Conclusions. The STSS demonstrates the suitability of modern amateur telescopes to detect and study faint, diffuse structures in large fields around nearby spiral galaxies. Their economic and accessibility advantages enable larger statistical samples with deep imaging, which are essential for testing galaxy formation models and constraining the frequency and properties of minor merger events in the local Universe.
  • Extragalactic stellar tidal streams: Observations meet simulation
    Juan Miró-Carretero, María A. Gómez-Flechoso, David Martínez-Delgado, Andrew P. Cooper, Santi Roca-Fàbrega, et al.
    Astronomy and Astrophysics, 2025
    Context. According to the well-established hierarchical framework for galaxy evolution, galaxies grow through mergers with other galaxies. The ΛCDM cosmological model predicts that the stellar halos of massive galaxies are rich in remnants resulting from minor mergers. Stellar Streams Legacy Survey (SSLS) has provided a first release of a catalogue with a statistically significant sample of stellar streams in the local Universe, detected in deep images from DESI Legacy Surveys and Dark Energy Survey (DES). Aims. The main objective is to compare observations of stellar tidal streams from the SSLS catalogue with predictions from state-of-the-art cosmological simulations regarding their abundance, up to a redshift of z < 0.02, according to the ΛCDM model. Methods. In particular, we used the outcome of cosmological simulations from Copernicus Complexio, TNG50 of the IllustrisTNG project, and Auriga to generate mock images of nearby halos and search for stellar streams. We compared the stream frequency and characteristics found in these images, as well as the results of a photometric analysis of the simulations data with DES observations. Results. We found a generally good agreement between the real images and the simulated ones regarding frequency and photometry of streams, while we found differences in the stream morphology between the observations and the simulations, and among the simulations themselves. By varying the sky background of the synthetic images to emulate different surface brightness limit levels, we were also able to obtain predictions for the detection rate of stellar tidal streams up to a surface brightness limit of 35 mag arcsec−2. Conclusions. The cosmological simulations predict that with an instrument akin to the one used in DES, it would be necessary to attain a surface brightness limit of 32 mag arcsec−2 in the r-band to achieve a frequency of up to ∼70% in the detection of stellar tidal streams around galaxies in the redshift range considered here.
  • Design and expert validation of a value-based indicator system for evaluating university peer mentoring programmes
    Journal of Further and Higher Education, 2025
  • Extragalactic stellar tidal streams in the Dark Energy Survey
    Juan Miró-Carretero, David Martínez-Delgado, María A. Gómez-Flechoso, Andrew Cooper, Mohammad Akhlaghi, et al.
    Astronomy and Astrophysics, 2024
    Context. Stellar tidal streams are a key tracer of galaxy evolution and have the potential to provide an indirect means for tracing dark matter. For the Local Group, many diffuse substructures have been identified and their link to galaxy evolution has been traced. However, the Local Group does not offer a statistically significant sample of stellar tidal streams. Thus, an analysis of a larger sample beyond the Local Group is required to better probe the frequency and characteristics of these streams to verify whether these properties are in agreement with the predictions of the ΛCDM model and its implementation in cosmological simulations, taking into account the impact of the baryonic physics modelling. Aims. The main scope of the Stellar Stream Legacy Survey is to obtain a statistically significant sample of stellar streams in the local Universe to be able to trace and study minor mergers and their contribution to galaxy evolution with respect to the ΛCDM theory. For that purpose, we are carrying out the first systematic survey of faint stellar debris from tidally disrupted dwarf satellites around nearby galaxies up to a distance of 100 Mpc. Methods. In this paper, we present a catalogue with the results of the first harvest of stellar tidal streams found by visual inspection in deep images of ∼700 galaxies from the Dark Energy Survey (DES). We also include, for the first time, a photometric characterisation of the streams obtained by measuring their surface brightnesses and colours. Results. We found a total of 63 streams in our sample at distances between 40 and 100 Mpc, including 58 that were not previously reported. We measured their average surface brightness for the g band, the r band and the z band, to be 28.35 ± 0.20, 27.81 ± 0.13, and 27.62 ± 0.09 mag arcsec−2, respectively. By applying a statistical analysis to our findings, we obtained a stream detection frequency of 9.1% ± 1.1% for the given surface brightness limit of the DES image sample, in agreement with previous studies. We identified stream progenitors in 5–14% of our stream sample, depending on the confidence level. Conclusions. The first catalogue of streams in the local Universe presented here will be complemented by future stream surveys within the Stellar Stream Legacy Survey and can be exploited in studies pertaining to galaxy evolution and cosmological models. In this work, we have learnt that the faintest measured stream surface brightness can be significantly brighter than the surface brightness limit of an image measured at the pixel level (in our case up to ∼1 mag arcsec−2 for the r band) mainly due to correlated noise present in the images.
  • The Origin of Kinematically Persistent Planes of Satellites as Driven by the Early Evolution of the Cosmic Web in ΛCDM
    Matías Gámez-Marín, Isabel Santos-Santos, Rosa Domínguez-Tenreiro, Susana E. Pedrosa, Patricia B. Tissera, et al.
    Astrophysical Journal, 2024
    Kinematically persistent planes (KPPs) of satellites are fixed sets of satellites co-orbiting around their host galaxy, whose orbital poles are conserved and clustered across long cosmic time intervals. They play the role of “skeletons,” ensuring the long-term durability of positional planes. We explore the physical processes behind their formation in terms of the dynamics of the local cosmic web (CW), characterized via the so-called Lagrangian volumes (LVs) built up around two zoom-in, cosmological hydro-simulations of Milky Way–mass disk galaxy + satellites systems, where three KPPs have been identified. By analyzing the LV deformations in terms of the reduced tensor of inertia (TOI), we find an outstanding alignment between the LV principal directions and the KPP satellites’ orbital poles. The most compressive local mass flows (along the e ˆ 3 eigenvector) are strong at early times, feeding the so-called e ˆ 3 -structure, while the smallest TOI axis rapidly decreases. The e ˆ 3 -structure collapse marks the end of this regime and is the timescale for the establishment of satellite orbital pole clustering when the Universe is ≲4 Gyr old. KPP protosatellites aligned with e ˆ 3 are those whose orbital poles are either aligned from early times or have been successfully bent at e ˆ 3 -structure collapse. KPP satellites associated with e ˆ 1 tend to have early trajectories already parallel to e ˆ 3 . We show that KPPs can arise as a result of the ΛCDM-predicted large-scale dynamics acting on particular sets of protosatellites, the same dynamics that shape the local CW environment.
  • Once in a blue stream: Detection of recent star formation in the NGC 7241 stellar stream with MEGARA
    David Martínez-Delgado, Santi Roca-Fàbrega, Armando Gil de Paz, Denis Erkal, Juan Miró-Carretero, et al.
    Astronomy and Astrophysics, 2024
    Aims. In this work we study the striking case of a narrow blue stream with a possible globular cluster-like progenitor around the NGC 7241 galaxy and its foreground dwarf companion. We want to figure out if the stream was generated by tidal interaction with NGC 7241 or if it first interacted with the foreground dwarf companion and later both fell together toward NGC 7241. Methods. We used four sets of observations, including a follow-up spectroscopic study of this stream based on data taken with the MEGARA instrument at the 10.4 m Gran Telescopio Canarias using the integral field spectroscopy mode, the Mount Lemmon 0.80 m telescope, the Telescopio Nazionale Galileo, the DESI Imaging Legacy surveys, and GALEX archival data. We also used high-resolution zoomed-in cosmological simulations. Results. Our data suggest that the compact object we detected in the stream is a foreground Milky Way halo star. Near this compact object we detect emission lines overlapping a less compact, bluer, and fainter blob of the stream that is clearly visible in both ultraviolet and optical deep images. From its heliocentric systemic radial velocity derived from the [O III]λ5007 Å lines (Vsyst = 1548.58 ± 1.80 km s−1) and new UV and optical broadband photometry, we conclude that this overdensity could be the actual core of the stream, with an absolute magnitude of Mg ∼ −10 and a g − r = 0.08 ± 0.11, consistent with a remnant of a low-mass dwarf satellite undergoing a current episode of star formation. From the width of the stream and assuming a circular orbit, we calculate that the progenitor mass can be typical of a dwarf galaxy, but it could also be substantially lower if the stream is on a very radial orbit or if it was created by tidal interaction with the companion dwarf instead of with NGC 7241. These estimates also suggest that this is one of the lowest mass streams detected to date beyond the Local Group. Finally, we find that blue stellar streams containing star formation regions are commonly predicted by high-resolution cosmological simulations of galaxies lighter than the Milky Way. This scenario is consistent with the processes explaining the bursty star formation history of some dwarf satellites, which are followed by a gas depletion and a fast quenching once they enter within the virial radius of their host galaxies for the first time. Thus, it is likely that the stream’s progenitor is undergoing a star formation burst comparable to those that have shaped the star formation history of several Local Group dwarfs in the last few gigayears.
  • Galactoseismology in cosmological simulations Vertical perturbations by dark matter, satellite galaxies, and gas
    B. García-Conde, T. Antoja, S. Roca-Fàbrega, F. Gómez, P. Ramos, et al.
    Astronomy and Astrophysics, 2024
    Context. Complex models recently became available for studying the dynamics of disk galaxies such as the Milky Way (MW). These models include the global dynamics from dwarf satellite galaxies, dark matter halo structure, gas infall, and stellar disks in a cosmological context. Aims. We use a MW model from a suite of high-resolution hydrodynamical cosmological simulations named GARROTXA to establish the relationship between the vertical disturbances seen in its galactic disk and multiple perturbations from the dark matter halo, satellites, and gas. Methods. We calculated the bending modes in the galactic disk in the last 6 Gyr of evolution. We computed the vertical acceleration exerted by dark matter and gas in order to quantify the impact of these components on the disk, and compared this with the bending behavior with Fourier analysis. Results. We find complex bending patterns at different radii and times, such as an inner retrograde mode with high frequency and an outer slower retrograde mode excited at different times. The amplitudes of these bending modes are highest during the early stages of formation of the thin disk (20 km s−1) and reach up to 8.5 km s−1 in the late disk evolution. We find that the infall of satellite galaxies leads to a tilt of the disk, and produces strong anisotropic gas accretion with a misalignment of 8° with subsequent star formation events and supernovae, creating significant vertical accelerations on the disk plane. The misalignment between the disk and the inner stellar and dark matter triaxial structure, which formed during the ancient assembly of the galaxy, also leads to a strong vertical acceleration of the stars. We also find dark matter subhalos that temporally coincide with the appearance of bending waves in certain periods. Conclusions. We conclude that several agents trigger the bending of the stellar disk and its phase spirals in this simulation, including satellite galaxies, dark subhalos, misaligned gaseous structures, and the inner dark matter profile. These phenomena coexist and influence each other, sometimes making it challenging to establish direct causality.
  • Effectiveness of a Peer Mentoring on University Dropout and Academic Performance
    Miguel A. Alonso, Aitana González-Ortiz-de-Zárate, M. Ángeles Gómez-Flechoso, Marco Castrillón
    Psicologia Educativa, 2024
  • Hidden depths in the local Universe: The Stellar Stream Legacy Survey
    David Martínez-Delgado, Andrew P. Cooper, Javier Román, Annalisa Pillepich, Denis Erkal, et al.
    Astronomy and Astrophysics, 2023
  • A search for stellar tidal streams around Milky Way analogues from the SAGA sample
    Juan Miró-Carretero, David Martínez-Delgado, Sílvia Farràs-Aloy, Maria A. Gómez-Flechoso, Andrew Cooper, et al.
    Astronomy and Astrophysics, 2023
  • A giant umbrella-like stellar stream around the tidal ring galaxy NGC 922
    David Martínez-Delgado, Santi Roca-Fàbrega, Juan Miró-Carretero, Maria Angeles Gómez-Flechoso, Javier Romàn, et al.
    Astronomy and Astrophysics, 2023
  • Planes of Satellites around Simulated Disk Galaxies. II. Time-persistent Planes of Kinematically Coherent Satellites in ΛCDM
    Isabel Santos-Santos, Matías Gámez-Marín, Rosa Domínguez-Tenreiro, Patricia B. Tissera, Lucas Bignone, et al.
    Astrophysical Journal, 2023
  • Planes of Satellites around Simulated Disk Galaxies. I. Finding High-quality Planar Configurations from Positional Information and Their Comparison to MW/M31 Data
    Isabel Santos-Santos, Rosa Domínguez-Tenreiro, Héctor Artal, Susana E. Pedrosa, Lucas Bignone, et al.
    Astrophysical Journal, 2020
  • Looking at the origin: Some insights into the general and fermentative microbiota of vineyard soils
    Alejandro Alonso, Miguel de Celis, Javier Ruiz, Javier Vicente, Eva Navascués, et al.
    Fermentation, 2019
  • Diversity of Saccharomyces cerevisiae yeasts associated to spontaneous and inoculated fermenting grapes from Spanish vineyards
    M. de Celis, J. Ruiz, M. Martín‐Santamaría, A. Alonso, D. Marquina, et al.
    Letters in Applied Microbiology, 2019
  • Understanding planes of satellites
    I. Santos-Santos, H. Artal, R. Domínguez-Tenreiro, P. B. Tissera, S. E. Pedrosa, et al.
    Proceedings of the International Astronomical Union, 2019
  • Understanding planes of satellites
    Proceedings of the 13th Scientific Meeting of the Spanish Astronomical Society Highlights of Spanish Astrophysics X Sea 2018, 2018
  • Wine yeasts identification by MALDI-TOF MS: Optimization of the preanalytical steps and development of an extensible open-source platform for processing and analysis of an in-house MS database
    Cristina Gutiérrez, M. Ángeles Gómez-Flechoso, Ignacio Belda, Javier Ruiz, Nour Kayali, et al.
    International Journal of Food Microbiology, 2017
  • DISCOVERY of AN ULTRA-DIFFUSE GALAXY in the PISCES-PERSEUS SUPERCLUSTER
    David Martínez-Delgado, Ronald Läsker, Margarita Sharina, Elisa Toloba, Jürgen Fliri, et al.
    Astronomical Journal, 2016
  • Ejemplos de análisis cuantitativo de imágenes de infrarrojos obtenidas por termografía activa para la detección de patologías de humedades
    Rehabend, 2014
  • The orbital distribution of satellite galaxies: Cosmological correlations and origin
    Proceedings of the 9th Scientific Meeting of the Spanish Astronomical Society Highlights of Spanish Astrophysics Vi Sea 2010, 2010
  • Shape and kinematics of elliptical galaxies: Evolution due to merging at z < 1.5
    A. C. González-García, J. Oñorbe, R. Domínguez-Tenreiro, M. Á. Gómez-Flechoso
    Astronomy and Astrophysics, 2009
  • The cosmological origin of the satellite distribution
    Nuovo Cimento Della Societa Italiana Di Fisica B, 2007
  • The cosmological origin of the satellite distribution
    A Century of Cosmology Past Present and Future, 2007
  • The cosmological structures and the orbits of satellite galaxies
    M.A. Gómez-Flechoso, L. Benjouali, H. Artal, R. Domínguez-Tenreiro
    Eas Publications Series, 2006
  • A comprehensive model for the Monoceros tidal stream
    J. Penarrubia, D. Martinez‐Delgado, H. W. Rix, M. A Gomez‐Flechoso, J. Munn, et al.
    Astrophysical Journal, 2005
  • Tracing out the northern tidal stream of the sagittarius dwarf spheroidal galaxy
    David Martinez‐Delgado, M. Angeles Gomez‐Flechoso, Antonio Aparicio, Ricardo Carrera
    Astrophysical Journal, 2004
  • A new method of estimating the mass-to-light ratio of the ursa minor dwarf spheroidal galaxy
    M. Ángeles Gómez-Flechoso, D. Martínez-Delgado
    Astrophysical Journal, 2003
  • Ram pressure stripping of dwarf satellites in disc galaxies
    M.A. Gómez-Flechoso
    Astrophysics and Space Science, 2001
  • Searching for tidal tails in Galactic dwarf spheroidal satellites
    D. MartÍnez-Delgado, A. Aparicio, M.A. Gómez-Flechoso
    Astrophysics and Space Science, 2001
  • Radial velocity of the Phoenix dwarf galaxy: Linking stars and H I GAS
    C. Gallart, D. Martínez-Delgado, M. A. Gómez-Flechoso, M. Mateo
    Astronomical Journal, 2001
  • On the stability of quasi-equilibrium self-gravitating configurations in a tidal field
    M. A. Gomez‐Flechoso, R. Dominguez‐Tenreiro
    Astrophysical Journal, 2001
  • Is the fast evolution scenario for virialized compact groups really compelling? The role of a dark massive group halo
    M. A. Gómez-Flechoso, R. Domínguez-Tenreiro
    Astrophysical Journal, 2001
  • Tidal streams in the galactic halo: Evidence for the sagittarius northern stream or traces of a new nearby dwarf galaxy
    David Martínez-Delgado, Antonio Aparicio, M. Ángeles Gómez-Flechoso, Ricardo Carrera
    Astrophysical Journal, 2001
  • A tidal extension in the Ursa Minor dwarf spheroidal galaxy
    D. Martínez-Delgado, J. Alonso-García, A. Aparicio, M. A. Gómez-Flechoso
    Astrophysical Journal, 2001
  • Structure in the velocity space of globular clusters
    E. J. Alfaro, A. J. Delgado, M. A. Gómez-Flechoso, F. Ferrini, I. Castro
    Astronomy and Astrophysics, 2001
  • Confidence limits of evolutionary synthesis models. III. On time-integrated quantities
    M. Cerviño, M. A. Gómez-Flechoso, F. J. Castander, D. Schaerer, M. Mollá, et al.
    Astronomy and Astrophysics, 2001
  • Sagittarius, a dwarf spheroidal galaxy without dark matter?
    Astronomy and Astrophysics, 1999
  • Dynamical friction for compound bodies
    R. Dominguez-Tenreiro, M. A. Gomez-Flechoso
    Monthly Notices of the Royal Astronomical Society, 1998
  • Dwarf spheroidal galaxies: Dynamical evolution
    M.A. Gómez-Flechoso
    Astrophysics and Space Science, 1998
  • The effects of cluster tides on disk galaxies
    Astrophysical Letters and Communications, 1997
  • Large-scale morphological segregation in optically selected galaxy redshift catalogs
    R. Dominguez-Tenreiro, A. Campos, M. A. Gomez-Flechoso, G. Yepes
    Astrophysical Journal, 1994
  • Scaling analysis of the distribution of galaxies in the CfA catalog
    R. Dominguez-Tenreiro, M. A. Gomez-Flechoso, V. J. Martinez
    Astrophysical Journal, 1994