The evolution of Balmer jump selected galaxies in the ALHAMBRA survey

We present a new color-selection technique, based on the Bruzual & Charlot models convolved with the bands of the ALHAMBRA survey, and the redshifted position of the Balmer jump to select star-forming galaxies in the redshift range 0.5 < z < 1.5. These galaxies are dubbed Balmer jump Galaxies BJGs. We apply the iSEDfit Bayesian approach to fit each detailed SED and determine star-formation rate (SFR), stellar mass, age and absolute magnitudes. The mass of the haloes where these samples reside are found via a clustering analysis. Five volume-limited BJG sub-samples with different mean redshifts are found to reside in haloes of median masses $\sim 10^{12.5 \pm 0.2} M_\odot$ slightly increasing toward z=0.5. This increment is similar to numerical simulations results which suggests that we are tracing the evolution of an evolving population of haloes as they grow to reach a mass of $\sim 10^{12.7 \pm 0.1} M_\odot$ at z=0.5. The likely progenitors of our samples at z$\sim$3 are Lyman Break Galaxies, which at z$\sim$2 would evolve into star-forming BzK galaxies, and their descendants in the local Universe are elliptical galaxies.Hence, this allows us to follow the putative evolution of the SFR, stellar mass and age of these galaxies. From z$\sim$1.0 to z$\sim$0.5, the stellar mass of the volume limited BJG samples nearly does not change with redshift, suggesting that major mergers play a minor role on the evolution of these galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star formation and possible minor mergers are the main channels of mass assembly.Comment: 14 pages, 10 figures. Submitted to A&A. It includes first referee's comments. Abstract abridged due to arXiv requirement

Evolution of Balmer jump selected galaxies in the ALHAMBRA survey

Extragalactic astronomy.-- et al.[Context]: Samples of star-forming galaxies at different redshifts have been traditionally selected via color techniques. The ALHAMBRA survey was designed to perform a uniform cosmic tomography of the Universe, and we here exploit it to trace the evolution of these galaxies. [Aims]: Our objective is to use the homogeneous optical coverage of the ALHAMBRA filter system to select samples of star-forming galaxies at different epochs of the Universe and study their properties. [Methods]: We present a new color-selection technique, based on the models of spectral evolution convolved with the ALHAMBRA bands and the redshifted position of the Balmer jump to select star-forming galaxies in the redshift range 0.5 <z< 1.5. These galaxies are dubbed Balmer-jump Galaxies (BJGs). We applied the iSEDfit Bayesian approach to fit each detailed spectral energy distribution and determined star-formation rate (SFR), stellar mass, age, and absolute magnitudes. The mass of the halos in which these samples reside were found through a clustering analysis. [Results]: Five volume-limited BJG subsamples with different mean redshifts are found to reside in halos of median masses ∼10 M slightly increasing toward z = 0.5. This increment is similar to numerical simulations results, which suggests that we trace the evolution of an evolving population of halos as they grow to reach a mass of ∼10 at z = 0.5. The likely progenitors of our samples at z ∼ 3 are Lyman-break galaxies, which at z ∼ 2 would evolve into star-forming BzK galaxies, and their descendants in the local Universe are galaxies with luminosities of 1-3 L. Hence, this allows us to follow the putative evolution of the SFR, stellar mass, and age of these galaxies. [Conclusions]: From z ∼ 1.0 to z ∼ 0.5, the stellar mass of the volume-limited BJG samples changes almost not at all with redshift, suggesting that major mergers play a minor role in the evolution of these galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star formation and possible minor mergers are the main channels of mass assembly.P.T. and A.M.A. acknowledge support from FONDECYT 3140542 and FONDECYT 3160776, respectively. L.I., A.M.A., P.T., S.G., N.P. acknowledge support from Basal-CATA PFB-06/2007. E.J.A. acknowledges support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grant AYA2013-40611-P. A.F.S., V.J.M. and P.A.M. acknowledge partial financial support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grant AYA2013-48623-C2-2, and from Generalitat Valenciana through project PrometeoII 2014/060. B.A. acknowledges received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 656354.Peer Reviewe

The ALHAMBRA survey : B−B-band luminosity function of quiescent and star-forming galaxies at 0.2≤z<10.2 \leq z < 1 by PDF analysis

Our goal is to study the evolution of the $B-$band luminosity function (LF) since $z=1$ using ALHAMBRA data. We used the photometric redshift and the $I-$band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with $I\leq24$ mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift-magnitude-galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also included in our analysis. We modelled the LF with a redshift-dependent Schechter function affected by the same selection effects than the data. The measured ALHAMBRA LF at $0.2\leq z<1$ and the evolving Schechter parameters both for quiescent and star-forming galaxies agree with previous results in the literature. The estimated redshift evolution of $M_B^* \propto Qz$ is $Q_{\rm SF}=-1.03\pm0.08$ and $Q_{\rm Q}=-0.80\pm0.08$, and of $\log \phi^* \propto Pz$ is $P_{\rm SF}=-0.01\pm0.03$ and $P_{\rm Q}=-0.41\pm0.05$. The measured faint-end slopes are $\alpha_{\rm SF}=-1.29\pm0.02$ and $\alpha_{\rm Q}=-0.53\pm0.04$. We find a significant population of faint quiescent galaxies, modelled by a second Schechter function with slope $\beta=-1.31\pm0.11$. We find a factor $2.55\pm0.14$ decrease in the luminosity density $j_B$ of star-forming galaxies, and a factor $1.25\pm0.16$ increase in the $j_B$ of quiescent ones since $z=1$, confirming the continuous build-up of the quiescent population with cosmic time. The contribution of the faint quiescent population to $j_B$ increases from 3% at $z=1$ to 6% at $z=0$. The developed methodology will be applied to future multi-filter surveys such as J-PAS.Comment: Accepted for publication in Astronomy and Astrophysics. 25 pages, 20 figures, 7 table

Galaxy clusters and groups in the ALHAMBRA Survey

We present a catalogue of 348 galaxy clusters and groups with $0.2<z<1.2$ selected in the 2.78 $deg^2$ ALHAMBRA Survey. The high precision of our photometric redshifts, close to $1\%$, and the wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder (BCF), whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both $70\%$ completeness and purity down to dark matter halo masses of $M_h\sim3\times10^{13}\rm M_{\odot}$ for $z<0.85$. Cluster redshifts are expected to be recovered with $\sim0.6\%$ precision for $z<1$. We also expect to measure cluster masses with $\sigma_{M_h|M^*_{CL}}\sim0.25-0.35\, dex$ precision down to $\sim3\times10^{13}\rm M_{\odot}$, masses which are $50\%$ smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour-magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z$<$0.5).Comment: Accepted for publication in MNRAS. Catalogues and figures available online and under the following link: http://bascaso.net46.net/ALHAMBRA_clusters.htm

A Ks-band-selected catalogue of objects in the ALHAMBRA survey

The original ALHAMBRA catalogue contained over 400,000 galaxies selected using a synthetic F814W image, to the magnitude limit AB(F814W)$\approx$24.5. Given the photometric redshift depth of the ALHAMBRA multiband data (=0.86) and the approximately $I$-band selection, there is a noticeable bias against red objects at moderate redshift. We avoid this bias by creating a new catalogue selected in the $K_s$ band. This newly obtained catalogue is certainly shallower in terms of apparent magnitude, but deeper in terms of redshift, with a significant population of red objects at $z>1$. We select objects using the $K_s$ band images, which reach an approximate AB magnitude limit $K_s \approx 22$. We generate masks and derive completeness functions to characterize the sample. We have tested the quality of the photometry and photometric redshifts using both internal and external checks. Our final catalogue includes $\approx 95,000$ sources down to $K_s \approx 22$, with a significant tail towards high redshift. We have checked that there is a large sample of objects with spectral energy distributions that correspond to that of massive, passively evolving galaxies at $z > 1$, reaching as far as $z \approx 2.5$. We have tested the possibility of combining our data with deep infrared observations at longer wavelengths, particularly Spitzer IRAC data

A Ks-band-selected catalogue of objects in the ALHAMBRA survey

Large scale structure and cosmolog

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

The ALHAMBRA survey⋆: B-band luminosity function of quiescent and star-forming galaxies at 0.2 ≤ z < 1 by PDF analysis

Lopez-Sanjuan, C. et. al.Aims. Our goal is to study the evolution of the B-band luminosity function (LF) since z ∼ 1 using ALHAMBRA data. Methods. We used the photometric redshift and the I-band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with I ≤ 24 mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift - magnitude - galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also included in our analysis. Results. We modelled the LF with a redshift-dependent Schechter function affected by the same selection effects than the data. The measured ALHAMBRA LF at 0.2 ≤ z < 1 and the evolving Schechter parameters both for quiescent and star-forming galaxies agree with previous results in the literature. The estimated redshift evolution of M∗B ∝ Qz is QSF = -1.03±0.08 and QQ = -0.80±0.08, and of log10φ∗ ∝ Pz is PSF = -0.01±0.03 and PQ = -0.41 ± 0.05. The measured faint-end slopes are αSF = -1.29 ± 0.02 and αQ = -0.53 ± 0.04. We find a significant population of faint quiescent galaxies with MB ≳ -18, modelled by a second Schechter function with slope β = -1.31 ± 0.11. Conclusions. We present a robust methodology to compute LFs using multi-filter photometric data. The application to ALHAMBRA shows a factor 2.55 ± 0.14 decrease in the luminosity density jB of star-forming galaxies, and a factor 1.25 ± 0.16 increase in the jB of quiescent ones since z = 1, confirming the continuous build-up of the quiescent population with cosmic time. The contribution of the faint quiescent population to jB increases from 3% at z = 1 to 6% at z = 0. The developed methodology will be applied to future multi-filter surveys such as J-PAS. © 2017 ESO.This work has been mainly funded by the FITE (Fondos de Inversiones de Teruel) and the projects AYA2015-66211-C2-1, AYA2012-30789, AYA200614056, and CSD2007-00060. We also acknowledge support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2010-15081, AYA2010-15169, AYA2010-22111-C03-01, AYA201022111- C03-02, AYA2011-29517-C03-01, AYA2012-39620, AYA2013-40611P, AYA2013-42227-P, AYA2013-43188-P, AYA2013-48623-C2-1, AYA201348623- C2-2, ESP2013-48274, AYA2014-58861-C3-1, Aragon Government Research Group E103, Generalitat Valenciana projects Prometeo 2009/064 and PROMETEOII/2014/060, Junta de Andalucia grants TIC114, JA2828, P10FQM-6444, and Generalitat de Catalunya project SGR-1398. E. T. acknowledges the support by the ETAg grants IUT26-2, IUT40-2, and by the European Regional Development Fund (TK133). A. M. acknowledges the financial support of the Brazilian funding agency FAPESP (Post-doc fellowship - process number 2014/11806-9). B. A. has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 656354.Peer reviewe

Galaxy clusters and groups in the ALHAMBRA survey

Ascaso, Begoña et al.We present a catalogue of 348 galaxy clusters and groups with 0.2 < z < 1.2 selected in the 2.78 deg2 Advanced Large, Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey. The high precision of our photometric redshifts, close to 1 per cent, and the wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder, whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both 70 per cent completeness and purity down to dark matter halo masses of Mh ∼ 3 × 1013 M⊙ for z < 0.85. Cluster redshifts are expected to be recovered with ∼0.6 per cent precision for z < 1. We also expect to measure cluster masses with σMh|M∗CL∼0.25-0.35dexσMh|MCL∗∼0.25-0.35dex precision down to ∼ 3 × 1013 M⊙, masses which are 50 per cent smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour–magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z < 0.5).We acknowledge support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2010-22111-C03-02, AYA2010-15169, AYA2012-30789, AYA2013-48623-C2-2, AYA2013-42227-P, AYA2013-40611-P, AYA2011-29517-C03-01, AYA2014-58861-C3-1, AYA2010-15081, Generalitat Valenciana projects PROMETEOII/2014/060, Junta de Andalucia grant TIC114, JA2828, Aragon Gorvernment-Research Group E103. MP acknowledges financial support from JAE-Doc program of the Spanish National Research Council (CSIC), co-funded by the European Social Fund. PAM acknowledges support from ERC StG Grant DEGAS-259586 and from the Science and Technology Facilities Council grants ST/K003305/1 and ST/L00075X/1.Peer Reviewe

A Ks-band-selected catalogue of objects in the ALHAMBRA survey

The original ALHAMBRA catalogue contained over 400 000 galaxies selected using a synthetic F814W image, to the magnitude limit AB(F814W) ≈ 24.5. Given the photometric redshift depth of the ALHAMBRA multiband data (〈 z〉 = 0.86) and the approximately I-band selection, there is a noticeable bias against red objects at moderate redshift.We avoid this bias by creating a new catalogue selected in the Ks band. This newly obtained catalogue is certainly shallower in terms of apparent magnitude, but deeper in terms of redshift, with a significant population of red objects at z > 1. We select objects using the Ks band images, which reach an approximate AB magnitude limit Ks ≈ 22. We generate masks and derive completeness functions to characterize the sample. We have tested the quality of the photometry and photometric redshifts using both internal and external checks. Our final catalogue includes ≈95 000 sources down to Ks ≈ 22, with a significant tail towards high redshift. We have checked that there is a large sample of objects with spectral energy distributions that correspond to that of massive, passively evolving galaxies at z > 1, reaching as far as z ≈ 2.5. We have tested the possibility of combining our data with deep infrared observations at longer wavelengths, particularly Spitzer IRAC data. © 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.This work was mainly supported by the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2010-22111-C03-02 and AYA2013-48623-C2-2, and by the Generalitat Valenciana through project PrometeoII 2014/060. We also acknowledge support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2012-39620, AYA2013-40611-P, AYA2013-42227-P, AYA2013-43188-P, AYA2013-48623-C2-1, ESP2013-48274, AYA2014-58861-C3-1, Junta de Andalucia grants TIC114, JA2828, P10-FQM-6444, and Generalitat de Catalunya project SGR-1398. BA has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 656354. PTI acknowledges support from CONICYT Chile grant FONDECYT 3140542.Peer reviewe