A5073890687- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Scientific Research and Discoveries
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Remote Sensing in Agriculture
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Adaptive optics and wavefront sensing
- Solar and Space Plasma Dynamics
- Advanced Vision and Imaging
- Solar Radiation and Photovoltaics
- Computational Physics and Python Applications
- Vehicle Routing Optimization Methods
- Forest Biomass Utilization and Management
- Remote Sensing and LiDAR Applications
- Cosmology and Gravitation Theories
- Smart Agriculture and AI
- Inertial Sensor and Navigation
- Neural Networks and Applications
- Optical Polarization and Ellipsometry
- CCD and CMOS Imaging Sensors
- Robotic Path Planning Algorithms
University of Concepción
2016-2025
Swinburne University of Technology
2013-2017
ETH Zurich
2010
Recent independent results from numerical simulations and observations have shown that brightest cluster galaxies (BCGs) increased their stellar mass by a factor of almost two between z~0.9 z~0.2. The further suggest more than half this is accreted through major mergers. Using sample 18 distant galaxy clusters with over 600 spectroscopically confirmed members them, we search for observational evidence mergers do play significant role. We find merger rate 0.38 +/- 0.14 per Gyr at z~1. While...
[abridged] The mass-size relation of early-type galaxies (ETGs) has been largely studied in the last years to probe mass assembly most massive objects Universe. In this paper, we focus on quiescent ETGs (Mstar/Msol > 3*10^10) living clusters (M200 ~ 10^14 Mstar) at 0.8< z <1.5, as compared those field same epoch. Our sample contains 400 and number field. Therefore, our is approximately an order magnitude larger than previous studies redshift range for galaxy clusters. We find that are...
We study the stellar mass functions (SMFs) of star-forming and quiescent galaxies in 11 galaxy clusters at 1.0<z<1.4, drawn from Gemini Observations Galaxies Rich Early Environments (GOGREEN) survey. Based on more than 500 hours Gemini/GMOS spectroscopy, deep multi-band photometry taken with a range observatories, we probe SMFs down to limit 10^9.7 Msun (10^9.5 for galaxies). At this early epoch, fraction is already highly elevated compared field same redshift. The quenched excess (QFE)...
Using a sample of 4 galaxy clusters at $1.35 < z 1.65$ and 10 $0.85 1.35$, we measure the environmental quenching timescale, $t_Q$, corresponding to time required after is accreted by cluster for it fully cease star formation. Cluster members are selected photometric-redshift criterion, categorized as star-forming, quiescent, or intermediate according their dust-corrected rest-frame colors magnitudes. We employ "delayed-then-rapid" model that relates simulated mass accretion rate observed...
We present results on the environmental dependence of star-forming galaxy main sequence in 11 cluster fields at $1.0 < z 1.5$ from Gemini Observations Galaxies Rich Early Environments Survey (GOGREEN) survey. use a homogeneously selected sample field and galaxies whose membership is derived dynamical analysis. Using [OII]-derived star formation rates (SFRs), we find that have suppressed SFRs fixed stellar mass comparison to their counterparts by factor 1.4 $\pm$ 0.1 ($\sim3.3\sigma$) across...
We describe a new Large Program in progress on the Gemini North and South telescopes: Observations of Galaxies Rich Early Environments (GOGREEN). This is an imaging deep spectroscopic survey 21 galaxy systems at $1<z<1.5$, selected to span factor $>10$ halo mass. The scientific objectives include measuring role environment evolution low-mass galaxies, dynamics stellar contents their host haloes. targets are from SpARCS, SPT, COSMOS SXDS surveys, be evolutionary counterparts today's clusters...
We study the star formation histories (SFHs) and mass-weighted ages of 331 UVJ-selected quiescent galaxies in 11 galaxy clusters field at 1<z<1.5 from Gemini Observations Galaxies Rich Early ENvironments (GOGREEN) survey. determine SFHs individual by simultaneously fitting rest-frame optical spectroscopy broadband photometry to stellar population models. confirm that are consistent with more massive having on average earlier times. Comparing found those field, we find $M_\ast<10^{11.3}$...
We use the EAGLE hydrodynamical simulation to trace quenching history of galaxies in its 10 most massive clusters. two criteria identify moments when suffer significant changes their star formation activity: {\it i)} instantaneous rate (SFR) strongest drop, $\Gamma_{\rm SFR}^{\rm SD}$, and ii)} a "quenching" criterion based on minimum threshold for specific SFR $\lesssim$ 10$^{-11}\rm yr^{-1}$. find that large fraction ($\gtrsim 60\%$) SD}$ outside cluster's R$_{200}$. This ``pre-processed"...
We present the first public data release of GOGREEN and GCLASS surveys galaxies in dense environments, spanning a redshift range $0.8<z<1.5$. The consist deep, multiwavelength photometry extensive Gemini GMOS spectroscopy 26 overdense systems ranging halo mass from small groups to most massive clusters. objective both projects was primarily understand how evolution is affected by their environment, determine physical processes that lead quenching star formation. There an emphasis on...
Abstract Understanding the processes that transform star-forming galaxies into quiescent ones is key to unraveling role of environment in galaxy evolution. We present measurements luminosity functions (LFs) and stellar mass (SMFs) passive red-sequence four clusters at 0.8 &lt; z 1.3, selected using deep VLT observations complemented with data from GCLASS GOGREEN surveys. find a significant enhancement abundance faint/low-mass both LFs SMFs all compared field. This further evidenced by...
We investigate the (large-scale) bar fraction in a mass-complete sample of M > 10^10.5 Msun disk galaxies at 0.2 < z 0.6 COSMOS field. The barred disks strongly depends on mass, morphology, and specific star formation rate (SSFR). At intermediate stellar mass (10^10.5 10^11 Msun) early-type is much higher, all redshifts, by factor ~2, than that late-type disks. This trend reversed higher (M Msun), where bars becomes significantly lower, fractions for with low high SSFRs closely follow those...
We investigate various galaxy population properties of the massive X-ray luminous cluster XDCP J0044.0-2033 at z=1.58, which constitutes most extreme matter density peak this redshift currently known. analyze deep VLT/HAWK-I NIR data in J- and Ks-bands, complemented by Subaru imaging i V, Spitzer observations 4.5 micron, new spectroscopic with VLT/FORS2. detect a cluster-associated excess about 90 galaxies, follows centrally peaked, compact NFW surface profile concentration c200~10. Based on...
We analyse the evolution of red sequence in a sample galaxy clusters at redshifts $0.8<z<1.5$ taken from HAWK-I Cluster Survey (HCS). The comparison with low-redshift ($0.04<z<0.08$) WIde-field Nearby Galaxy-cluster (WINGS) and other literature results shows that slope intrinsic scatter cluster have undergone little since $z=1.5$. find luminous-to-faint ratio faint end luminosity distribution HCS are consistent those measured WINGS, implying there is no deficit galaxies magnitudes fainter...
We present the WiFeS Atlas of Galactic Globular cluster Spectra, a library integrated spectra Milky Way and Local Group globular clusters. used integral field spectrograph on Australian National University 2.3 m telescope to observe central regions 64 clusters 22 hosted by Way's low mass satellite galaxies. The have wider wavelength coverage (3300 {\AA} 9050 {\AA}) higher spectral resolution (R = 6800) than existing libraries By including Large Small Magellanic Cloud star clusters, we extend...
We aim to characterize the relationship between dust properties. also provide equations estimate accurate properties from limited observational datasets. assemble a sample of 1,630 nearby (z<0.1) galaxies-over large range Mstar, SFR - with multi-wavelength observations available wise, iras, planck and/or SCUBA. The characterization emission comes SED fitting using Draine & Li models, which we parametrize two components (warm and cold ). subsample these galaxies global measurements CO HI are...
We present a detailed analysis of galaxy colours in two clusters at \mbox{z $\sim$ 0.4}, \mbox{MACS J0416.1-2403} and J1206.2-0847}, drawn from the CLASH-VLT survey, to investigate role pre-processing quenching star formation. estimate fractions red blue galaxies within main cluster detected substructures study trends colour as function projected distance substructure centres. Our results show that members have consistent spatial distributions. In particular, inside follow same observed...
We use photometric redshifts and statistical background subtraction to measure stellar mass functions in galaxy group-mass ($4.5-8\times10^{13}~\mathrm{M}_\odot$) haloes at $1<z<1.5$. Groups are selected from COSMOS SXDF, based on X-ray imaging sparse spectroscopy. Stellar ($M_{\mathrm{stellar}}$) computed for quiescent star-forming galaxies separately, their rest-frame $UVJ$ colours. From these we compute the fraction excess (QFE) relative field as a function of $M_{\mathrm{stellar}}$. QFE...
We measure the rate of environmentally-driven star formation quenching in galaxies at $z\sim 1$, using eleven massive ($M\approx 2\times10^{14}\,\mathrm{M}_\odot$) galaxy clusters spanning a redshift range $1.0<z<1.4$ from GOGREEN sample. identify three different types transition galaxies: "green valley" (GV) identified their rest-frame $(NUV-V)$ and $(V-J)$ colours; "blue quiescent" (BQ) galaxies, found blue end quiescent sequence $(U-V)$ colour; spectroscopic post-starburst (PSB) galaxies....
Using data from the WiFeS Atlas of Galactic Globular cluster Spectra we study behaviour calcium triplet (CaT), a popular metallicity indicator in extragalactic stellar population studies. A major caveat these studies is that potential sensitivity to other parameters such as age, abundance and initial mass function has not yet been empirically evaluated. Here present measurements strength CaT feature for 113 globular clusters Milky Way its satellite galaxies. We derive empirical calibrations...
We present a study of the evolution brightest cluster galaxies (BCGs) in sample clusters at $0.05 \leq z<0.35$ from SDSS and WISE with halo masses range $6 \times 10^{13}M_\odot$ (massive groups) - $10^{15.5}M_\odot$ (Coma-like clusters). analyse optical infrared colours stellar BCGs as function mass their host haloes. find that are mostly red quiescent minority ($\sim 9$\%) them star-forming. $g-r$ consistent those sequence same redshifts; however, we detect presence tail blue star-forming...
We present visual-like morphologies over 16 photometric bands, from ultraviolet to near-infrared, for 8412 galaxies in the Cluster Lensing And Supernova survey with Hubble (CLASH) obtained using a convolutional neural network (ConvNet) model. Our model follows Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) main morphological classification scheme, obtaining probability each galaxy at CLASH band of being spheroid, disk, irregular, point source, or unclassifiable. catalog...
Recent observations have shown that the environmental quenching of galaxies at z ~ 1 is qualitatively different to in local Universe. However, physical origin these differences has not yet been elucidated. In addition, while low-redshift comparisons between observed trends and predictions cosmological hydrodynamical simulations are now routine, there relatively few higher redshifts date. Here we confront three state-of-the-art suites (BAHAMAS+MACSIS, EAGLE+Hydrangea, IllustrisTNG) with field...
The study of galaxy morphology is fundamental to understand the physical processes driving structural evolution galaxies. It has long been known that dense environments host high fractions early-type galaxies and low late-type galaxies, indicating environment affects In this paper we present an analysis morphological composition red sequence in a sample 9 clusters at $0.8<z<1.5$ drawn from HAWK-I cluster survey (HCS), with aim investigating evolutionary paths different morphologies. We...