Observations cosmologiques avec un télescope grand champ spatial: Simulations pixels du spectromètre sans fente d'EUCLID

The observations of the supernovae, the cosmic microwave background, and more recently the measurement of baryon acoustic oscillations and the weak lensing effects, converge to a Lambda CDM model, with an accelerating expansion of the today Universe. This model need two dark components to fit the observations, the dark matter and the dark energy. Two approaches seem particularly promising to measure both geometry of the Universe and growth of dark matter structures, the analysis of the weak distortions of distant galaxies by gravitational lensing and the study of the baryon acoustic oscillations. Both methods required a very large sky surveys of several thousand square degrees. In the context of the spectroscopic survey of the space mission EUCLID, dedicated to the study of the dark side of the universe, I developed a pixel simulation tool for analyzing instrumental performances. The proposed method can be summarized in three steps. The first step is to simulate the observables, ie mainly the sources of the sky. I work up a new method, adapted for spectroscopic simulations, which allows to mock an existing survey of galaxies in ensuring that the distribution of the spectral properties of galaxies are representative of current observations, in particular the distribution of the emission lines. The second step is to simulate the instrument and produce images which are equivalent to the expected real images. Based on the pixel simulator of the HST, I developed a new tool to compute the images of the spectroscopic channel of EUCLID. The new simulator have the particularity to be able to simulate PSF with various energy distributions and detectors which have different pixels. The last step is the estimation of the performances of the instrument. Based on existing tools, I set up a pipeline of image processing and performances measurement. My main results were: 1) to validate the method by simulating an existing survey of galaxies, the WISP survey, 2) to determine the tolerances on the energy distribution of the PSF for the slitless spectrometer of EUCLID, 3) to determine the tolerances on the properties of near-infrared detectors of EUCLID.Les observations des supernovae, du fond diffus cosmologique, et plus récemment la mesure des oscillations acoustiques des baryons et des effets de lentilles gravitationnelles faibles, favorisent le modèle cosmologique Lambda CDM pour lequel l'expansion de l'Univers est actuellement en accélération. Ce modèle fait appel à deux composants insaisissables, la matière sombre et l'énergie sombre. Deux approches semblent particulièrement prometteuses pour sonder à la fois la géométrie de l'Univers et la croissance des structures de matière noire, l'analyse des distorsions faibles des galaxies lointaines par cisaillement gravitationnel et l'étude des oscillations acoustiques des baryons. Ces deux méthodes demandent de très grands relevés du ciel, de plusieurs milliers de degrés carrés, en imagerie et en spectroscopie. Dans le contexte du relevé spectroscopique de la mission spatiale EUCLID, dédiée à l'étude des composantes sombres de l'univers, j'ai réalisé des simulations pixels permettant l'analyse des performances instrumentales. La méthode proposée peut se résumer en trois étapes. La première étape est de simuler les observables, c'est à dire principalement les sources du ciel. Pour cela j'ai développé une nouvelle méthode, adapté à la spectroscopie, qui permet d'imiter un relevé existant, en s'assurant que la distribution des propriétés spectrales des galaxies soit représentative des observations actuelles, en particulier la distribution des raies d'émission. La seconde étape est de simuler l'instrument et de produire des images équivalentes aux images réelles attendues. En me basant sur le simulateur pixel du HST, j'ai développé un nouvel outil permettant de simuler les images en spectroscopie sans fente d'EUCLID. Le nouveau simulateur a la particularité de pouvoir simuler des PSF avec une distribution d'énergie variée et des détecteurs dont chaque pixel est différent. La dernière étape est l'estimation des performances de l'instrument. Encore en me basant sur les outils existant, j'ai mis en place un pipeline de traitement des images et de mesure de performances. Mes résultat principaux ont été : 1) de valider la méthode en simulant un relevé de galaxies existant, le relevé WISP, 2) de déterminer les tolérances sur la distribution d'énergie de la PSF du spectromètre sans fente d'EUCLID, 3) de déterminer les tolérances sur les propriétés de détecteurs proche infrarouge d'EUCLID

The WFIRST Galaxy Survey Exposure Time Calculator

This document describes the exposure time calculator for the Wide-Field Infrared Survey Telescope (WFIRST) high-latitude survey. The calculator works in both imaging and spectroscopic modes. In addition to the standard ETC functions (e.g. background and S/N determination), the calculator integrates over the galaxy population and forecasts the density and redshift distribution of galaxy shapes usable for weak lensing (in imaging mode) and the detected emission lines (in spectroscopic mode). The source code is made available for public use.Comment: 44 pages. The current C source code and version history can be found at http://www.tapir.caltech.edu/~chirata/web/software/space-etc/ ; IPAC maintains a web interface at http://wfirst-web.ipac.caltech.edu/wfDepc/wfDepc.js

Observations cosmologiques avec un télescope grand champ spatial : Simulations pixels du spectromètre sans fente d'EUCLID

Les observations des supernovae, du fond diffus cosmologique, et plus récemment la mesure des oscillations acoustiques des baryons et des effets de lentilles gravitationnelles faibles, favorisent le modèle cosmologique LambdaCDM pour lequel l'expansion de l'Univers est actuellement en accélération. Ce modèle fait appel à deux composants insaisissables, la matière sombre et l'énergie sombre. Deux approches semblent particulièrement prometteuses pour sonder à la fois la géométrie de l'Univers et la croissance des structures de matière noire, l'analyse des distorsions faibles des galaxies lointaines par cisaillement gravitationnel et l'étude des oscillations acoustiques des baryons. Ces deux méthodes demandent de très grands relevés du ciel, de plusieurs milliers de degrés carrés, en imagerie et en spectroscopie. Dans le contexte du relevé spectroscopique de la mission spatiale EUCLID, dédiée à l'étude des composantes sombres de l'univers, j'ai réalisé des simulations pixels permettant l'analyse des performances instrumentales. La méthode proposée peut se résumer en trois étapes. La première étape est de simuler les observables, c'est à dire principalement les sources du ciel. Pour cela j'ai développé une nouvelle méthode, adapté à la spectroscopie, qui permet d'imiter un relevé existant, en s'assurant que la distribution des propriétés spectrales des galaxies soit représentative des observations actuelles, en particulier la distribution des raies d'émission. La seconde étape est de simuler l'instrument et de produire des images équivalentes aux images réelles attendues.The observations of the supernovae, the cosmic microwave background, and more recently the measurement of baryon acoustic oscillations and the weak lensing effects, converge to a LambdaCDM model, with an accelerating expansion of the today Universe. This model need two dark components to fit the observations, the dark matter and the dark energy. Two approaches seem particularly promising to measure both geometry of the Universe and growth of dark matter structures, the analysis of the weak distortions of distant galaxies by gravitational lensing and the study of the baryon acoustic oscillations. Both methods required a very large sky surveys of several thousand square degrees. In the context of the spectroscopic survey of the space mission EUCLID, dedicated to the study of the dark side of the universe, I developed a pixel simulation tool for analyzing instrumental performances. The proposed method can be summarized in three steps.The first step is to simulate the observables, ie mainly the sources of the sky. I work up a new method, adapted for spectroscopic simulations, which allows to mock an existing survey of galaxies in ensuring that the distribution of the spectral properties of galaxies are representative of current observations, in particular the distribution of the emission lines. The second step is to simulate the instrument and produce images which are equivalent to the expected real images. Based on the pixel simulator of the HST, I developed a new tool to compute the images of the spectroscopic channel of EUCLID. The new simulator have the particularity to be able to simulate PSF with various energy distributions and detectors which have different pixel

Euclid flight H2RG IR detectors: per pixel conversion gain from on-ground characterization for the Euclid NISP instrument

International audienceEuclid is a major ESA mission for the study of dark energy planned to launch in 2021. Euclid will probe the expansion history of the Universe using weak lensing and baryonic acoustic oscillations probes. A survey of 15,000 deg2 of the sky with the instrument NISP (Near-Infrared Spectro-Photometer), in the 900 – 2100 nm band, will give both the photometric and spectrometric redshifts of tens of millions of galaxies. The 16 H2RG detectors of the NISP focal plane array are still being characterized at CPPM (Marseille). Already 16 out of 20 flight detectors have been tested and a straightforward analysis done. Performance of the dedicated test benches – in particular control of flux and temperature – as well as an overview of the test flow will be presented. This paper will present methods and some preliminary results on two detectors focusing on the determination of a per pixel conversion gain

Detector chain calibration strategy for the Euclid Flight IR H2RGs

International audienceEuclid is an ESA mission to map the geometry of the Dark Universe with a planned launch date in 2021.1 Two primary cosmological probes, weak gravitational lensing and baryonic acoustic oscillations, are implemented through a VISible imager (VIS) and a Near-Infrared Spectrometer and Photometer (NISP).2 The ground characterization of the NISP Flight Sensor Chip Systems (SCS) followed by the pixel response calibration aims to produce all informations to correct and control the accuracy of the signal. This work reports on the ground characterization of the NISP detector chain. The detector and electrical effects are likely to generate statistical fluctuations and systematic errors on the final flux measurement. The analysis strategies to maintain the pixel relative response accuracy within 1% is proposed in this work. The Euclid NISP test ow is presented and the main concerns of the detector chain calibration, such as non-linearity, charge trapping and de-trapping are discussed on the basis of the analysis of the flight detectors characterization data

The 0.1 < z < 1.65 evolution of the bright end of the OII luminosity function

We present the [Oii] (λλ3729,3726) luminosity function measured in the redshift range 0.

LISA AIVT Optical Ground Support Equipement technology developments

International audienceThe LISA space interferometer aims at GW detection with »3x10-20/√Hz strain sensitivity, resulting in a displacement sensitivity of 11pm/√Hz over a path length of 2.5x109 m in the frequency range from 3x10-5 to 1 Hz.The LISA France Collaboration is in charge of the ground optical tests of the MOSA (Moving Optical Sub-Assembly), including the Optical Bench, Telescope and Gravitational Reference Sensor. Special check-out equipment is required, such as the Far-Field Optical Ground Support Equipment aiming at measuring the Tilt-To-Length coupling coefficient between angular residual beam jitter and longitudinal path length. The FF-OGSE simulates the incoming jittering beam and measures the associated longitudinal path length change.We present two prototypes – the Zerodur InterFerOmeter and the TTL-OB - that will demonstrate the optical performance, the functional tests, the limits on sensitivity and the precision of the path length measurements achievable on-ground. These two benches are the first part of the design and specification for the FF-OGSE.The Stray Light OGSE aims at stray light characterization in the integrated MOSA. It measures and identifies, separately, the different sources of stray light through the measurement of the corresponding fringe patterns while scanning the laser’s optical frequency

LISA AIVT Optical Ground Support Equipement technology developments

International audienceThe LISA space interferometer aims at GW detection with »3x10-20/√Hz strain sensitivity, resulting in a displacement sensitivity of 11pm/√Hz over a path length of 2.5x109 m in the frequency range from 3x10-5 to 1 Hz.The LISA France Collaboration is in charge of the ground optical tests of the MOSA (Moving Optical Sub-Assembly), including the Optical Bench, Telescope and Gravitational Reference Sensor. Special check-out equipment is required, such as the Far-Field Optical Ground Support Equipment aiming at measuring the Tilt-To-Length coupling coefficient between angular residual beam jitter and longitudinal path length. The FF-OGSE simulates the incoming jittering beam and measures the associated longitudinal path length change.We present two prototypes – the Zerodur InterFerOmeter and the TTL-OB - that will demonstrate the optical performance, the functional tests, the limits on sensitivity and the precision of the path length measurements achievable on-ground. These two benches are the first part of the design and specification for the FF-OGSE.The Stray Light OGSE aims at stray light characterization in the integrated MOSA. It measures and identifies, separately, the different sources of stray light through the measurement of the corresponding fringe patterns while scanning the laser’s optical frequency

LISA AIVT Optical Ground Support Equipement technology developments

International audienceThe LISA space interferometer aims at GW detection with »3x10-20/√Hz strain sensitivity, resulting in a displacement sensitivity of 11pm/√Hz over a path length of 2.5x109 m in the frequency range from 3x10-5 to 1 Hz.The LISA France Collaboration is in charge of the ground optical tests of the MOSA (Moving Optical Sub-Assembly), including the Optical Bench, Telescope and Gravitational Reference Sensor. Special check-out equipment is required, such as the Far-Field Optical Ground Support Equipment aiming at measuring the Tilt-To-Length coupling coefficient between angular residual beam jitter and longitudinal path length. The FF-OGSE simulates the incoming jittering beam and measures the associated longitudinal path length change.We present two prototypes – the Zerodur InterFerOmeter and the TTL-OB - that will demonstrate the optical performance, the functional tests, the limits on sensitivity and the precision of the path length measurements achievable on-ground. These two benches are the first part of the design and specification for the FF-OGSE.The Stray Light OGSE aims at stray light characterization in the integrated MOSA. It measures and identifies, separately, the different sources of stray light through the measurement of the corresponding fringe patterns while scanning the laser’s optical frequency

LISA AIVT Optical Ground Support Equipement technology developments

International audienceThe LISA space interferometer aims at GW detection with »3x10-20/√Hz strain sensitivity, resulting in a displacement sensitivity of 11pm/√Hz over a path length of 2.5x109 m in the frequency range from 3x10-5 to 1 Hz.The LISA France Collaboration is in charge of the ground optical tests of the MOSA (Moving Optical Sub-Assembly), including the Optical Bench, Telescope and Gravitational Reference Sensor. Special check-out equipment is required, such as the Far-Field Optical Ground Support Equipment aiming at measuring the Tilt-To-Length coupling coefficient between angular residual beam jitter and longitudinal path length. The FF-OGSE simulates the incoming jittering beam and measures the associated longitudinal path length change.We present two prototypes – the Zerodur InterFerOmeter and the TTL-OB - that will demonstrate the optical performance, the functional tests, the limits on sensitivity and the precision of the path length measurements achievable on-ground. These two benches are the first part of the design and specification for the FF-OGSE.The Stray Light OGSE aims at stray light characterization in the integrated MOSA. It measures and identifies, separately, the different sources of stray light through the measurement of the corresponding fringe patterns while scanning the laser’s optical frequency