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The Large Synoptic Survey Telescope (LSST; http://lsst.org) is aplanned, large-aperture, wide-field, ground-based telescope thatwill survey half the sky every few nights in six optical bands from320 to 1050 nm. It will explore a wide range of astrophysicalquestions, ranging from discovering “killer” asteroids, to examiningthe nature of dark energy. The LSST will produce on average 15 terabytes of data per night,yielding an (uncompressed) data set of over 100 petabytes at theend of its 10-year mission. To enable the wide variety of plannedscience, the LSST Project is leading the construction of a new,general-purpose, high-performance, scalable, well documented,open source data processing software stack for O/IR surveys.Prototypes of this stack are already capable of processing datafrom existing cameras (e.g., SDSS, DECam, MegaCam), and formthe basis of the Hyper Supreme-Cam (HSC) Survey data reductionpipeline. In the 2020-ies, running on dedicated HPC facilities, thissystem will enable us to process the LSST data stream in near realtime, with full-dataset reprocessings on annual scale. In this talk, I will review the science goals and the technical designof the LSST, focusing on the data management system, itsarchitecture, the software stack, and the products it will generate. Iwill discuss the exciting opportunities it presents for LSST, and theastronomical software community as a whole. More broadly, I willalso discuss implications of petascale data sets for astronomy inthe 2020s, and ways in which the astronomical community canprepare to make the best use of them. &nbsp

The Large Synoptic Survey Telescope (LSST) is an 8-m optical ground-based telescope being constructed on Cerro Pachon in Chile. LSST will survey half the sky every few nights in six optical bands. The data will be transferred to NCSA and within 60 seconds they will be reduced using difference imaging techniques and detected transients will be announced to the community in the VOEvent format. Annual data releases will be made from all the data during the 10-year mission, with unprecedented depth of coadds and time resolution of catalogs for such a large region of sky. In this paper we present the current status of the data processing software, and describe how to obtain it., Comment: 4 pages, poster paper presented at the Astronomical Data Analysis Software and Systems XXV Conference held in October 2015 in Sydney, Australia

The LSST telescope (Large Synoptic Survey Telescope) is part of the new generation of opticalinstruments whose aim is to achieve a complete map of the Universe. With its wide and largefield of view, it will observed billions of galaxies, in six optical photometric bands. allowing thestudy of many scientifcc subjects. In particular, LSST data will accurately measure Dark Energyparameters through four distinct probes: supernovae, week lensing, clusters and Baryon AcousticOscillations (BAO). The combination of those different probes should allowed the discriminationbetween theoretical models describing the dark energy. This thesis is part of the development ofthe LSST project and presents both an instrumental and a phenomenological study. First, thework concerning the development of the optical calibration bench for LSST's camera is presented.The measurements then performed led to the establishment of the light source final design.The calibration bench will thus allow measurement of the camera focal plan response withinthe six wavelength corresponding to LSST filters. We then present a complete analysis chainwhose objective is to estimate the accuracy with which the characteristics BAOs scale should bemeasured considering LSST simulated data. With this aim,a galaxy catalog were simulate froma CDM cosmology. An enhanced template setting method has been developed, combined withstatistical tests, it allowed a significant improvement of the photo-z reconstruction quality up,in agreement with LSST requirements. A study of the impact of the filterslters transmission curvesallowed the optimization of their bandwidth and showed the importance of their calibration.Finally the BAOs scale was estimated taking into account the photo-z errors, compelling thewhole simulation., Le télescope LSST (Large Synoptic Survey Telescope) fait partie de la nouvelle générationd'instruments optiques ayant pour objectif la réalisation d'une cartographie complète de l'Univers.Son champ de vue, à la fois large et profond, va conduire à l'observation de milliards d'objets, encouvrant la moitié du ciel dans six bandes photométriques. Les données issues des observationsde LSST vont notamment permettre de contraindre les paramètres d'énergie noire avec uneprécision dix fois meilleure que les contraintes actuelles. Quatre des différentes sondes observationnellessensibles au contenu énergétique de l'Univers seront accessible à LSST : les supernovaede type Ia, les amas de galaxies, les lentilles gravitationnelles et les oscillations acoustiques debaryons (BAO). La combinaison de ces sondes devrait permettre de différencier les différentsmodèles théoriques décrivant l'énergie noire. Cette thèse s'inscrit dans le cadre du projet LSSTet présente à la fois un aspect instrumental et une étude phénoménologique. Dans un premiertemps, le travail concernant le développement d'un banc d'étalonnage optique pour la camérasera présenté. Les mesures alors effectuées ont conduit à l'établissement du design canal de lasource de lumière. Le banc d'étalonnage va ainsi permettre une mesure précise de la réponsedu plan focal de la caméra dans les longueurs d'ondes associées aux six filtres de LSST. Nousprésenterons ensuite une chaine d'analyse complète dont l'objectif est d'estimer la précision aveclaquelle il sera possible de mesurer l'échelle caractéristiques des BAOs à partir des données deLSST. Dans ce but un catalogue de galaxies a été simulé à partir d'une cosmologie CDM.L'utilisation d'une méthode de template tting, combinée à différents tests statistiques a permisl'obtention de redshifts photométriques (photo-z) de bonne qualité, respectant les spécificationsLSST. Une étude portant sur l'impact de la transmission des filtres a permis l'optimisation deleur bande-passante et a montré l'importance de leur étalonnage. Enfin l'échelle caractéristiquedes BAO a été estimé en tenant compte des erreurs photo-z, validant l'ensemble de la chaine desimulation.

Temnáenergietvořícípřibližně70%hmotyvesmíruz·stávájednouznejvětšch záhad moderní fyziky. K pochopení její podstaty jsou potřeba přesná kosmolog- ická měření. Jedním z projekt· zkoumající tuto exotickou formu hmoty bude i Large Synoptic Survey Telescope, který pom·že potvrdit či vyvrátit standardní kosmologický model (ΛCDM). Pro úspěch projektu je potřeba prozkoumat r·zné teorie temné energie. Jednou z alternativních teoríí vysvětlujících urychlenou expanzi vesmíru je tzv. chameleoní gravitace. Chameleon je nové skalární pole s hmotou závisející na okolní hustotě. V hustých prostředích jako je například Sluneční soustava získává pole velkou hmotu a propaguje se pouze na malých vzdálenostech díky čemuž m·že uniknout standardním test·m gravitace. V prá- ci mimo jiné studujeme chování chameleoního pole v okolí hvězd a v galaxiích. Ukazujeme také za jakých okolností je toto pole možné detekovat pomocí spek- troskopických měření a slabého čočkování.

An overview of the image differencing approach being developed for the Large Synoptic Survey Telescope.

The Large Synoptic Survey Telescope (LSST; http://lsst.org) is a planned, large-aperture, wide-field, ground-based telescope that will survey half the sky every few nights in six optical bands from 320 to 1050 nm. It will explore a wide range of astrophysical questions, from studies of the Solar System, to examining the nature of dark energy. LSST is an integrated survey system. The observatory, telescope, camera and data management systems will be built to conduct the LSST survey and will not support 'PI mode' in the classical sense. Instead, the ultimate, science-enabling, deliverable of LSST will be the fully reduced data. This poster presents the baseline design and contents of LSST data products. There will be three main categories. "Level 1" data products will be generated continuously every observing night and include measurements such as alerts to objects that have changed brightness or position. They will be broadcast world-wide using VO protocols. "Level 2" data products will be made available as annual Data Releases and will include images and measurements of quantities such as positions, fluxes, and shapes, as well as variability information such as orbital parameters for moving objects and an appropriate compact description of light curves. The exact contents of Level 2 products will be set by the desire to minimize the necessity to independently reprocess the image data. Finally, approximately 10% of LSST's computing capability will be made available to the community for generation of "Level 3" data products. These will be used to perform custom analyses not fully enabled by Level 1/2, while taking advantage of co-location of computation with the entire LSST data set.

Preliminary overview presentation on the LSST Winter 2013 Stripe 82 Data Challenge.

A status update from the Large Synoptic Survey Telescope Data Management team.

This thesis work focuses on the use of deep, wide field surveys to extract new cosmological information. Precise photometry plays a large role in this quest, through the determination of photometric redshifts and the propagation of photometric errors into the cosmological results. This is a unifying theme which effectively ties both parts of the thesis together. After a general review of cosmology and the measurements that support the ΛCDM model, and a description of the Large Synoptic Survey Telescope (LSST), the first part of this work deals with the influence of the variation of main atmospheric constituents on ground-based photometry, focusing particularly on the LSST site at Cerro Pachón, Chile. We process all recent available data on ozone, water vapor and aerosols to construct a long-term atmospheric simulation and estimate quantitatively how the spatial and temporal gradients of these constituents would affect LSST calibration process. The second part of this work starts with a theoretical description of gravitational lensing, concentrating on the weak lensing aspect. After discussing the advantages and difficulties of cosmic shear measurements, we explore the use of cosmic magnification, together with the redshift tomography enabled by the LSST, to constrain cosmological models. We find that cosmic magnification covariance is beset by intrinsic clustering but nevertheless represents a useful probe of galaxy bias and dark energy that complements cosmic shear, and which can increase the robustness of cosmological constraints from lensing surveys., Ce travail de thèse se focalise sur l'usage de grands sondages pour extraire de l'information sur la cosmologie. Une photométrie de précision joue un rôle clé dans cette quête à travers la détermination de redshifts photométriques ainsi que la propagation des erreurs dans les résultats cosmologiques ; thème unissant les deux parties de cette thèse. Après une revue de la cosmologie et des mesures favorisant le modèle ΛCDM, ainsi qu'une description du Large Synoptic Survey Telescope (LSST), la première partie de ce travail se porte sur l'étude de la variation des principaux constituants de l'atmosphère sur la photométrie au sol, au niveau du site du LSST à Cerro Pachón, au Chili. Nous utilisons des données récentes sur l'ozone, la vapeur d'eau et les aérosols pour en construire une simulation de longue durée et estimer quantitativement l'influence des gradients spatiaux et temporels de ces constituants sur la procédure de la calibration du LSST. La deuxième partie de ce travail débute par une description théorique de l'effet de lentille gravitationnelle, avec un accent sur le lentillage faible. Après une comparaison des avantages et inconvénients inhérents aux mesures de cisaillement cosmique, nous explorons l'utilisation de l'amplification cosmique conjointement à la séparation tomographique en redshift permise par le LSST afin de contraindre les modèles. Nous trouvons que l'amplification cosmique, bien qu'affectée par le clustering intrinsèque, représente une sonde prometteuse du biais des galaxies et de l'énergie noire, complémentaire au cisaillement cosmique, et qui augmente la robustesse des contraintes cosmologiques provenant des mêmes relevés.

The Large Synoptic Survey Telescope (LSST) is an 8-m optical ground- based telescope being constructed on Cerro Pachon in Chile. LSST will survey half the sky every few nights in six optical bands. LSST Education and Public Outreach (EPO) is investigating requirements and technologies to create a next generation sky viewer. We discuss and survey current sky viewer technologies and identify new features re- quired for an LSST EPO Skyviewer.

The Large Synoptic Survey Telescope (LSST) is an 8-m optical ground- based telescope being constructed on Cerro Pachon in Chile. LSST will survey half the sky every few nights in six optical bands. LSST Education and Public Outreach (EPO) is investigating requirements and technologies to create a next generation sky viewer. We discuss and survey current sky viewer technologies and identify new features re- quired for an LSST EPO Skyviewer.