Examinando por Autor "Demarco, Ricardo"
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Ítem Gemini Observations of Galaxies in Rich Early Environments (GOGREEN) I: Survey description(Oxford University Press, 2017-10) Balogh, Michael L.; Gilbank, David G.; Muzzin, Adam; Rudnick, Gregory; Cooper, Michael C.; Lidman, Chris; Biviano, Andrea; Demarco, Ricardo; McGee, Sean L.; Nantais, Julie B.; Noble, Allison; Old, Lyndsay; Wilson, Gillian; Yee, Howard K.C.; Bellhouse, Callum; Cerulo, Pierluigi; Chan, Jeffrey; Pintos-Castro, Irene; Simpson, Rane; van der Burg, Remco F.J.; Zaritsky, Dennis; Ziparo, Felicia; Alonso, María Victoria; Bower, Richard G.; Lucia, Gabriella De; Finoguenov, Alexis; Lambas, Diego Garcia; Muriel, Hernan; Parker, Laura C.; Rettura, Alessandro; Valotto, Carlos; Wetzel, AndrewWe describe a new Large Program in progress on the Gemini North and South telescopes: Gemini Observations of Galaxies in Rich Early Environments (GOGREEN). This is an imaging and deep spectroscopic survey of 21 galaxy systems at 1 < z < 1.5, selected to span a factor >10 in halo mass. The scientific objectives include measuring the role of environment in the evolution of low-mass galaxies, and measuring the dynamics and stellar contents of their host haloes. The targets are selected from the SpARCS, SPT, COSMOS, and SXDS surveys, to be the evolutionary counterparts of today's clusters and groups. The newred-sensitive Hamamatsu detectors on GMOS, coupled with the nod-and-shuffle sky subtraction, allow simultaneous wavelength coverage over λ ~ 0.6-1.05 μm, and this enables a homogeneous and statistically complete redshift survey of galaxies of all types. The spectroscopic sample targets galaxies with AB magnitudes z' < 24.25 and [3.6] μm < 22.5, and is therefore statistically complete for stellar masses M* ≳ 1010.3M⊙, for all galaxy types and over the entire redshift range. Deep, multiwavelength imaging has been acquired over larger fields for most systems, spanning u through K, in addition to deep IRAC imaging at 3.6 μm. The spectroscopy is ~50 per cent complete as of semester 17A, and we anticipate a final sample of ~500 new cluster members. Combined with existing spectroscopy on the brighter galaxies from GCLASS, SPT, and other sources, GOGREEN will be a large legacy cluster and field galaxy sample at this redshift that spectroscopically covers a wide range in stellar mass, halo mass, and clustercentric radius. © 2017 The Authors.Ítem The GOGREEN Survey: Evidence of an Excess of Quiescent Disks in Clusters at 1.0(IOP Publishing Ltd, 2021-10-10) Chan, Jeffrey C. C.; Wilson, Gillian; Balogh, Michael; Rudnick, Gregory; van der Burg, Remco F. J.; Muzzin, Adam; Webb, Kristi A.; Biviano, Andrea; Cerulo, Pierluigi; Cooper, M. C.; De Lucia, Gabriella; Demarco, Ricardo; Forrest, Ben; Jablonka, Pascale; Lidman, Chris; McGee, Sean L.; Nantais, Julie; Old, Lyndsay; Pintos-Castro, Irene; Poggianti, Bianca; Reeves, Andrew M. M.; Vulcani, Benedetta; Yee, Howard K. C.; Zaritsky, DennisWe present the results of the measured shapes of 832 galaxies in 11 galaxy clusters at 1.0 < z < 1.4 from the GOGREEN survey. We measure the axis ratio (q), the ratio of the minor to the major axis, of the cluster galaxies from near-infrared Hubble Space Telescope imaging using Sersic profile fitting and compare them with a field sample. We find that the median q of both star-forming and quiescent galaxies in clusters increases with stellar mass, similar to the field. Comparing the axis ratio distributions between clusters and the field in four mass bins, the distributions for star-forming galaxies in clusters are consistent with those in the field. Conversely, the distributions for quiescent galaxies in the two environments are distinct, most remarkably in where clusters show a flatter distribution, with an excess at low q. Modelling the distribution with oblate and triaxial components, we find that the cluster and field sample difference is consistent with an excess of flattened oblate quiescent galaxies in clusters. The oblate population contribution drops at high masses, resulting in a narrower q distribution in the massive population than at lower masses. Using a simple accretion model, we show that the observed q distributions and quenched fractions are consistent with a scenario where no morphological transformation occurs for the environmentally quenched population in the two intermediate-mass bins. Our results suggest that environmental quenching mechanism(s) likely produce a population that has a different morphological mix than those resulting from the dominant quenching mechanism in the field.Ítem GOGREEN: A critical assessment of environmental trends in cosmological hydrodynamical simulations at z ≈ 1(Oxford University Press, 2023-01-01) Kukstas, Egidijus; Balogh, Michael L.; McCarthy, Ian G.; Bahé, Yannick M.; De Lucia, Gabriella; Jablonka, Pascale; Vulcani, Benedetta; Baxter, Devontae C.; Biviano, Andrea; Cerulo, Pierluigi; Chan, Jeffrey C.; Cooper, M. C.; Demarco, Ricardo; Finoguenov, Alexis; Font, Andreea S.; Lidman, Chris; Marchioni, Justin; McGee, Sean; Muzzin, Adam; Nantais, Julie; Old, Lyndsay; Pintos-Castro, Irene; Poggianti, Bianca; Reeves, Andrew M. M.; Rudnick, Gregory; Sarron, Florian; van der Burg, Remco; Webb, Kristi; Wilson, Gillian; Yee, Howard K. C.; Zaritsk, DennisRecent observations have shown that the environmental quenching of galaxies at z ∼1 is qualitatively different to that in the local Universe. However, the physical origin of these differences has not yet been elucidated. In addition, while low-redshift comparisons between observed environmental trends and the predictions of cosmological hydrodynamical simulations are now routine, there have been relatively few comparisons at higher redshifts to date. Here we confront three state-of-the-art suites of simulations (BAHAMAS+MACSIS, EAGLE+Hydrangea, IllustrisTNG) with state-of-the-art observations of the field and cluster environments from the COSMOS/UltraVISTA and GOGREEN surveys, respectively, at z ∼1 to assess the realism of the simulations and gain insight into the evolution of environmental quenching. We show that while the simulations generally reproduce the stellar content and the stellar mass functions of quiescent and star-forming galaxies in the field, all the simulations struggle to capture the observed quenching of satellites in the cluster environment, in that they are overly efficient at quenching low-mass satellites. Furthermore, two of the suites do not sufficiently quench the highest mass galaxies in clusters, perhaps a result of insufficient feedback from AGN. The origin of the discrepancy at low stellar masses (M* ≲ 1010 M⊙), which is present in all the simulations in spite of large differences in resolution, feedback implementations, and hydrodynamical solvers, is unclear. The next generation of simulations, which will push to significantly higher resolution and also include explicit modelling of the cold interstellar medium, may help us to shed light on the low-mass tension.Ítem GOGREEN: A critical assessment of environmental trends in cosmological hydrodynamical simulations at z ≈ 1(Oxford University Press, 2023-01) Kukstas, Egidijus; Balogh, Michael L.; Mccarthy, Ian G.; Bahe, Yannick M.; De Lucia, Gabriella; Jablonka, Pascale; Vulcani, Benedetta; Baxter, Devontae C.; Biviano, Andrea; Cerulo, Pierluigi; Chan, Jeffrey C.; Cooper M.C.; Demarco, Ricardo; Finoguenov, Alexis; Font, Andreea S.; Lidman, Chris; Marchioni, Justin; Mcgee, Sean; Muzzin, Adam; Nantais, Julie; Old, Lyndsay; Pintos-Castro, Irene; Poggianti, Bianca; Reeves, Andrew M. M.; Rudnick, Gregory; Sarron, Florian; Van Der Burg, Remco; Webb, Kristi; Wilson, Gillian; Yee, Howard K. C.; Zaritsky, DennisRecent observations have shown that the environmental quenching of galaxies at z ∼1 is qualitatively different to that in the local Universe. However, the physical origin of these differences has not yet been elucidated. In addition, while low-redshift comparisons between observed environmental trends and the predictions of cosmological hydrodynamical simulations are now routine, there have been relatively few comparisons at higher redshifts to date. Here we confront three state-of-the-art suites of simulations (BAHAMAS+MACSIS, EAGLE+Hydrangea, IllustrisTNG) with state-of-the-art observations of the field and cluster environments from the COSMOS/UltraVISTA and GOGREEN surveys, respectively, at z ∼1 to assess the realism of the simulations and gain insight into the evolution of environmental quenching. We show that while the simulations generally reproduce the stellar content and the stellar mass functions of quiescent and star-forming galaxies in the field, all the simulations struggle to capture the observed quenching of satellites in the cluster environment, in that they are overly efficient at quenching low-mass satellites. Furthermore, two of the suites do not sufficiently quench the highest mass galaxies in clusters, perhaps a result of insufficient feedback from AGN. The origin of the discrepancy at low stellar masses (M* ≲ 1010 M⊙), which is present in all the simulations in spite of large differences in resolution, feedback implementations, and hydrodynamical solvers, is unclear. The next generation of simulations, which will push to significantly higher resolution and also include explicit modelling of the cold interstellar medium, may help us to shed light on the low-mass tension. © 2022 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.Ítem The GOGREEN Survey: A deep stellar mass function of cluster galaxies at 1.0 < z < 1.4 and the complex nature of satellite quenching(EDP Sciences, 2020-06-01) van der Burg, Remco F. J.; Rudnick, Gregory; Balogh, Michael L.; Muzzin, Adam; Lidman, Chris; Old, Lyndsay J.; Shipley, Heath; Gilbank, David; McGee, Sean; Biviano, Andrea; Cerulo, Pierluigi; Chan, Jeffrey C. C.; Cooper, Michael; De Lucia, Gabriella; Demarco, Ricardo; Forrest, Ben; Gwyn, Stephen; Jablonka, Pascale; Kukstas, Egidijus; Marchesini, Danilo; Nantais, Julie; Noble, Allison; Pintos-Castro, Irene; Poggianti, Bianca; Reeves, Andrew M. M.; Stefanon, Mauro; Vulcani, Benedetta; Webb, Kristi; Wilson, Gillian; Yee, Howard; Zaritsky, DennisWe study the stellar mass functions (SMFs) of star-forming and quiescent galaxies in 11 galaxy clusters at 1.0 < z < 1.4 drawn from the Gemini Observations of Galaxies in Rich Early ENvironments (GOGREEN) survey. Based on more than 500 h of Gemini/GMOS spectroscopy and deep multi-band photometry taken with a range of observatories, we probe the SMFs down to a stellar mass limit of 109.7 M (109.5 M for star-forming galaxies). At this early epoch, the fraction of quiescent galaxies is already highly elevated in the clusters compared to the field at the same redshift. The quenched fraction excess (QFE) represents the fraction of galaxies that would be star-forming in the field but are quenched due to their environment. The QFE is strongly mass dependent, and increases from ∼30% at M? = 109.7 M to ∼80% at M? = 1011.0 M . Nonetheless, the shapes of the SMFs of the two individual galaxy types, star-forming and quiescent galaxies, are identical between cluster and field to high statistical precision. Nevertheless, along with the different quiescent fractions, the total galaxy SMF is also environmentally dependent, with a relative deficit of low-mass galaxies in the clusters. These results are in stark contrast with findings in the local Universe, and therefore require a substantially different quenching mode to operate at early times. We discuss these results in light of several popular quenching models.