Browsing by Author "Lagos, C. D. P."

Now showing 1 - 4 of 4
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    Angular momentum evolution in dark matter haloes: a study of the Bolshoi and Millennium simulations
    (2017) Contreras Hantke, Sergio A.; Padilla, Nelson; Lagos, C. D. P.
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    Halo merger tree comparison: impact on galaxy formation models
    (2022) Gomez, Jonathan S.; Padilla, N. D.; Helly, J. C.; Lacey, C. G.; Baugh, C. M.; Lagos, C. D. P.
    We examine the effect of using different halo finders and merger tree building algorithms on galaxy properties predicted using the galform semi-analytical model run on a high resolution, large volume dark matter simulation. The halo finders/tree builders hbt, rockstar, subfind, and VELOCI raptor differ in their definitions of halo mass, on whether only spatial or phase-space information is used, and in how they distinguish satellite and main haloes; all of these features have some impact on the model galaxies, even after the trees are post-processed and homogenized by galform. The stellar mass function is insensitive to the halo and merger tree finder adopted. However, we find that the number of central and satellite galaxies in galform does depend slightly on the halo finder/tree builder. The number of galaxies without resolved subhaloes depends strongly on the tree builder, with VELOCIraptor, a phase-space finder, showing the largest population of such galaxies. The distributions of stellar masses, cold and hot gas masses, and star formation rates agree well between different halo finders/tree builders. However, because VELOCIraptor has more early progenitor haloes, with these trees galform produces slightly higher star formation rate densities at high redshift, smaller galaxy sizes, and larger stellar masses for the spheroid component. Since in all cases these differences are small we conclude that, when all of the trees are processed so that the main progenitor mass increases monotonically, the predicted galform galaxy populations are stable and consistent for these four halo finders/tree builders.
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    The better half - asymmetric star formation due to ram pressure in the EAGLE simulations
    (2020) Troncoso Iribarren, P.; Padilla, Nelson; Santander, C.; Lagos, C. D. P.; García Lambas, D.; Rodríguez, S.; Contreras, S.
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    The MAGPI survey: Science goals, design, observing strategy, early results and theoretical framework
    (2021) Foster, C.; Mendel, J. T.; Lagos, C. D. P.; Wisnioski, E.; Yuan, T.; D'Eugenio, F.; Barone, T. M.; Harborne, K. E.; Vaughan, S. P.; Schulze, F.; Remus, R-S.; Gupta, A.; Collacchioni, F.; Khim, D. J.; Taylor, P.; Bassett, R.; Croom, S. M.; McDermid, R. M.; Poci, A.; Battisti, A. J.; Bland-Hawthorn, J.; Bellstedt, S.; Colless, M.; Davies, L. J. M.; Derkenne, C.; Driver, S.; Ferre-Mateu, A.; Fisher, D. B.; Gjergo, E.; Johnston, E. J.; Khalid, A.; Kobayashi, C.; Oh, S.; Peng, Y.; Robotham, A. S. G.; Sharda, P.; Sweet, S. M.; Taylor, E. N.; Tran, K. -V. H.; Trayford, J. W.; van de Sande, J.; Yi, S. K.; Zanisi, L.
    We present an overview of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, a Large Program on the European Southern Observatory Very Large Telescope. MAGPI is designed to study the physical drivers of galaxy transformation at a look-back time of 3-4 Gyr, during which the dynamical, morphological, and chemical properties of galaxies are predicted to evolve significantly. The survey uses new medium-deep adaptive optics aided Multi-Unit Spectroscopic Explorer (MUSE) observations of fields selected from the Galaxy and Mass Assembly (GAMA) survey, providing a wealth of publicly available ancillary multi-wavelength data. With these data, MAGPI will map the kinematic and chemical properties of stars and ionised gas for a sample of 60 massive (>7 x 10(10) M-circle dot) central galaxies at 0.25 < z < 0.35 in a representative range of environments (isolated, groups and clusters). The spatial resolution delivered by MUSE with Ground Layer Adaptive Optics (0.6 - 0.8 arcsec FWHM) will facilitate a direct comparison with Integral Field Spectroscopy surveys of the nearby Universe, such as SAMI and MaNGA, and at higher redshifts using adaptive optics, for example, SINS. In addition to the primary (central) galaxy sample, MAGPI will deliver resolved and unresolved spectra for as many as 150 satellite galaxies at 0.25 < z < 0.35, as well as hundreds of emission-line sources at z < 6. This paper outlines the science goals, survey design, and observing strategy of MAGPI. We also present a first look at the MAGPI data, and the theoretical framework to which MAGPI data will be compared using the current generation of cosmological hydrodynamical simulations including EAGLE, MAGNETICUM, HORIZON-AGN, and ILLUSTRIS-TNG. Our results show that cosmological hydrodynamical simulations make discrepant predictions in the spatially resolved properties of galaxies at z approximate to 0.3. MAGPI observations will place new constraints and allow for tangible improvements in galaxy formation theory.