Uso de imágenes térmicas para la determinación del estado hídrico de cerezos jóvenes

Comunicación presentada al XXXVII Congreso Nacional de Riegos, celebrado en Don Benito del 4 al 6 de Junio de 2019 y organizada por la Asociación Española de Riegos y Drenajes y la Universidad de ExtremaduraEn regiones áridas y semiáridas, donde el principal factor limitante de la producción es el agua, es clave la aplicación exacta y cuidadosa de los volúmenes de riego de acuerdo con un criterio de programación técnico-económico. En este sentido, el uso de las nuevas tecnologías puede contribuir a la mejora de la eficiencia de uso del agua y sostenibilidad de la agricultura. Con el objetivo de evaluar el uso de imágenes térmicas para determinar el estado hídrico del cultivo y su idoneidad para el manejo del riego se realizó un ensayo en cerezos jóvenes (Prunus avium L.) ‘Lapins’ en 2018. Se establecieron dos tratamientos de riego: i) control, CTL, regado al 115% de la evapotranspiración del cultivo (ETc) durante todo el periodo experimental y ii) déficit severo, SS, regado como CTL hasta finales de junio, momento a partir del cual se alternaron 2 ciclos consecutivos de supresión-reanudación del riego, tras la recuperación del árbol se inició el segundo ciclo. La respuesta de la planta fue proporcional a la intensidad del estrés alcanzado durante los periodos de supresión del riego. Así, la disminución del stock hídrico del suelo provocó la caída del potencial hídrico de tallo y el aumento en la temperatura de la copa. Tras la reanudación del riego, todos los indicadores estudiados alcanzaron valores similares a CTL. El índice térmico obtenido a partir de la diferencia entre las temperaturas del dosel vegetal y la del aire circundante fue un buen indicador del estado hídrico de cerezos jóvenes bajo déficit hídrico severo.Ministerio de Economía, Industria y Competitividad del Gobierno de España, MINECO (Ref. AGL2016-77282-C3-3-R) y la Fundación Séneca de la Región de Murcia (Grupo de excelencia 2016-2019, Ref. 19895/GERM/15

Sistema para la asistencia en la orientación de termo-radiómetros para procesos de medida de temperatura foliar

Poster presentado al XXXVII Congreso Nacional de Riegos, celebrado en Don Benito del 4 al 6 de Junio de 2019 y organizada por la Asociación Española de Riegos y Drenajes y la Universidad de ExtremaduraDesarrollar un nuevo equipo portátil de bajo coste y manejo, para asistir en el proceso de instalación y orientación de termo-radiómetros (IR-120 Campbell Scientific). El equipo diseñado mide en continuo y a distancia la temperatura de copa de árboles en riego completo a través del termo-radiómetro y la compara con la del aire circundante; para ello dispone de un sensor de temperatura y humedad ambiental. Dicha información se muestra en la pantalla.• Ministerio de Economía, Industria y Competitividad (AGL2016-77282-C3-R) • Ministerio de Educación, Cultura y Deporte (FPU17/05155) • Fundación Séneca de la región de Murcia (19895/GERM/15

Influencia del riego deficitario en la aparición de desordenes fisiológicos en cerezas ‘Prime Giant’

Comunicación presentada al XXXVII Congreso Nacional de Riegos, celebrado en Don Benito del 4 al 6 de Junio de 2019 y organizada por la Asociación Española de Riegos y Drenajes y la Universidad de ExtremaduraSe describen los resultados agronómicos obtenidos en un ensayo de riego deficitario controlado realizado en cerezos (Prunus avium L.) combinación ’Prime Giant’/SL64, durante cuatro campañas (2015-2018) en Jumilla (Murcia, España). Los tratamientos de riego ensayados fueron: CTL, regado al 110% ETcg (evapotranspiración del cultivo bajo riego por goteo) durante toda la campaña de riego y RDC con riego al 100% de ETcg durante precosecha y diferenciación floral y al 55% de ETcg el resto de postcosecha. Se monitorizó el potencial matricial de agua en el suelo (Ψm) y se midió periódicamente el potencial hídrico de tallo a mediodía (Ψt). Los diferentes volúmenes de riego promedios aplicados anualmente, 6949 y 4249 m3 ha-1 para CTL y RDC respectivamente, provocaron diferencias significativas en la disponibilidad de agua para la planta y en su estado hídrico durante la postcosecha de todos los años de estudio. Sin embargo, estas diferencias no provocaron que el rendimiento de los cerezos sometidos a RDC fuera menor o mayor proporción de frutos dobles, cuya presencia resultó altamente dependiente de la temperatura del aire durante los primeros días de la postcosecha del año previo. Sí que se observó que los frutos de los árboles bajo RDC presentaban una menor proporción de frutos partidos en cosecha y en los análisis de inducción de partidura en laboratorio.• Ministerio de Economía, Industria y Competitividad del Gobierno de España (MINECO) y Fondo Europeo de Desarrollo Regional (Ref. AGL2016-77282-C3-3-R y AGL2013-49047-C2-1-R) • Fundación Séneca de la Región de Murcia (Grupo de excelencia 2016-2019 Ref. 19895/GERM/15) • Universidad Politécnica de Cartagena (UPCT): beca de iniciación a la actividad investigadora (Víctor Blanco

Euclid Collaboration IV: Impact of Undetected Galaxies on Weak-Lensing Shear Measurements

In modern weak-lensing surveys, the common approach to correct for residual systematic biases in the shear is to calibrate shape measurement algorithms using simulations. These simulations must fully capture the complexity of the observations to avoid introducing any additional bias. In this paper we study the importance of faint galaxies below the observational detection limit of a survey. We simulate simplified Euclid VIS images including and excluding this faint population, and measure the shift in the multiplicative shear bias between the two sets of simulations. We measure the shear with three different algorithms: a moment-based approach, model fitting, and machine learning. We find that for all methods, a spatially uniform random distribution of faint galaxies introduces a shear multiplicative bias of the order of a few times $10^{-3}$. This value increases to the order of $10^{-2}$ when including the clustering of the faint galaxies, as measured in the Hubble Space Telescope Ultra-Deep Field. The magnification of the faint background galaxies due to the brighter galaxies along the line of sight is found to have a negligible impact on the multiplicative bias. We conclude that the undetected galaxies must be included in the calibration simulations with proper clustering properties down to magnitude 28 in order to reach a residual uncertainty on the multiplicative shear bias calibration of a few times $10^{-4}$, in line with the $2\times10^{-3}$ total accuracy budget required by the scientific objectives of the Euclid survey. We propose two complementary methods for including faint galaxy clustering in the calibration simulations.Comment: Version published in A&

Euclid : Superluminous supernovae in the Deep Survey

Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z similar to 4 and therefore, offer the possibility of probing the distant Universe. Aims. We aim to investigate the possibility of detecting SLSNe-I using ESA's Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods. We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS. To estimate the uncertainties, we calculated their distribution with two different set-ups, namely optimistic and pessimistic, adopting different star formation densities and rates. We also applied a standardization method to the peak magnitudes to create a simulated Hubble diagram to explore possible cosmological constraints. Results. We show that Euclid should detect approximately 140 high-quality SLSNe-I to z similar to 3.5 over the first five years of the mission (with an additional 70 if we lower our photometric classification criteria). This sample could revolutionize the study of SLSNe-I at z > 1 and open up their use as probes of star-formation rates, galaxy populations, the interstellar and intergalactic medium. In addition, a sample of such SLSNe-I could improve constraints on a time-dependent dark energy equation-of-state, namely w (a), when combined with local SLSNe-I and the expected SN Ia sample from the Dark Energy Survey. Conclusions. We show that Euclid will observe hundreds of SLSNe-I for free. These luminous transients will be in the Euclid data-stream and we should prepare now to identify them as they offer a new probe of the high-redshift Universe for both astrophysics and cosmology.Peer reviewe

Euclid preparation. III. Galaxy cluster detection in the wide photometric survey, performance and algorithm selection

Galaxy cluster counts in bins of mass and redshift have been shown to be a competitive probe to test cosmological models. This method requires an efficient blind detection of clusters from surveys with a well-known selection function and robust mass estimates, which is particularly challenging at high redshift. The Euclid wide survey will cover 15 000 deg2 of the sky, avoiding contamination by light from our Galaxy and our solar system in the optical and near-infrared bands, down to magnitude 24 in the H-band. The resulting data will make it possible to detect a large number of galaxy clusters spanning a wide-range of masses up to redshift ∼2 and possibly higher. This paper presents the final results of the Euclid Cluster Finder Challenge (CFC), fourth in a series of similar challenges. The objective of these challenges was to select the cluster detection algorithms that best meet the requirements of the Euclid mission. The final CFC included six independent detection algorithms, based on different techniques, such as photometric redshift tomography, optimal filtering, hierarchical approach, wavelet and friend-of-friends algorithms. These algorithms were blindly applied to a mock galaxy catalog with representative Euclid-like properties. The relative performance of the algorithms was assessed by matching the resulting detections to known clusters in the simulations down to masses of M₂₀₀ ∼ 10^(13.25) M⊙. Several matching procedures were tested, thus making it possible to estimate the associated systematic effects on completeness to 80% completeness for a mean purity of 80% down to masses of 10¹⁴ M⊙ and up to redshift z = 2. Based on these results, two algorithms were selected to be implemented in the Euclid pipeline, the Adaptive Matched Identifier of Clustered Objects (AMICO) code, based on matched filtering, and the PZWav code, based on an adaptive wavelet approach

Euclid: On the reduced shear approximation and magnification bias for Stage IV cosmic shear experiments

Stage IV weak lensing experiments will offer more than an order of magnitude leap in precision. We must therefore ensure that our analyses remain accurate in this new era. Accordingly, previously ignored systematic effects must be addressed. In this work, we evaluate the impact of the reduced shear approximation and magnification bias, on the information obtained from the angular power spectrum. To first-order, the statistics of reduced shear, a combination of shear and convergence, are taken to be equal to those of shear. However, this approximation can induce a bias in the cosmological parameters that can no longer be neglected. A separate bias arises from the statistics of shear being altered by the preferential selection of galaxies and the dilution of their surface densities, in high-magnification regions. The corrections for these systematic effects take similar forms, allowing them to be treated together. We calculate the impact of neglecting these effects on the cosmological parameters that would be determined from Euclid, using cosmic shear tomography. We also demonstrate how the reduced shear correction can be calculated using a lognormal field forward modelling approach. These effects cause significant biases in Omega_m, n_s, sigma_8, Omega_DE, w_0, and w_a of -0.51 sigma, -0.36 sigma, 0.37 sigma, 1.36 sigma, -0.66 sigma, and 1.21 sigma, respectively. We then show that these lensing biases interact with another systematic: the intrinsic alignment of galaxies. Accordingly, we develop the formalism for an intrinsic alignment-enhanced lensing bias correction. Applying this to Euclid, we find that the additional terms introduced by this correction are sub-dominant

Euclid: the selection of quiescent and star-forming galaxies using observed colours

The Euclid mission will observe well over a billion galaxies out to z ∼ 6 and beyond. This will offer an unrivalled opportunity to investigate several key questions for understanding galaxy formation and evolution. The first step for many of these studies will be the selection of a sample of quiescent and star-forming galaxies, as is often done in the literature by using well-known colour techniques such as the ‘UVJ’ diagram. However, given the limited number of filters available for the Euclid telescope, the recovery of such rest-frame colours will be challenging. We therefore investigate the use of observed Euclid colours, on their own and together with ground-based u-band observations, for selecting quiescent and star-forming galaxies. The most efficient colour combination, among the ones tested in this work, consists of the (u − VIS) and (VIS − J) colours. We find that this combination allows users to select a sample of quiescent galaxies complete to above ∼70 per cent and with less than 15 per cent contamination at redshifts in the range 0.75 65 per cent completeness level and contamination below 20 per cent at 1 < z < 2 for finding quiescent galaxies. In comparison, the sample of quiescent galaxies selected with the traditional UVJ technique is only ∼20 per cent complete at z < 3, when recovering the rest-frame colours using mock Euclid observations. This shows that our new methodology is the most suitable one when only Euclid bands, along with u-band imaging, are available

Euclid: the selection of quiescent and star-forming galaxies using observed colours

The Euclid mission will observe well over a billion galaxies out to z ∼ 6 and beyond. This will offer an unrivalled opportunity to investigate several key questions for understanding galaxy formation and evolution. The first step for many of these studies will be the selection of a sample of quiescent and star-forming galaxies, as is often done in the literature by using well-known colour techniques such as the ‘UVJ’ diagram. However, given the limited number of filters available for the Euclid telescope, the recovery of such rest-frame colours will be challenging. We therefore investigate the use of observed Euclid colours, on their own and together with ground-based u-band observations, for selecting quiescent and star-forming galaxies. The most efficient colour combination, among the ones tested in this work, consists of the (u − VIS) and (VIS − J) colours. We find that this combination allows users to select a sample of quiescent galaxies complete to above ∼70 per cent and with less than 15 per cent contamination at redshifts in the range 0.75 65 per cent completeness level and contamination below 20 per cent at 1 < z < 2 for finding quiescent galaxies. In comparison, the sample of quiescent galaxies selected with the traditional UVJ technique is only ∼20 per cent complete at z < 3, when recovering the rest-frame colours using mock Euclid observations. This shows that our new methodology is the most suitable one when only Euclid bands, along with u-band imaging, are available