Download or read book Contraintes spectroscopiques sur les populations stellaires written by Pierre Ocvirk and published by . This book was released on 2005 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Etude spectroscopique de la r gion centrale M 31 written by Monique Joly and published by . This book was released on 1972 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synth se des populations stellaires dans les galaxies proches written by Jihane Moultaka and published by . This book was released on 2001 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Populations stellaires dans les galaxies h tes de noyaux actifs written by Julien Fremaux and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: La population stellaire des galaxies hôtes de noyau actif semble entretenir une relation étroite avec le degré d'activité du noyau. Ces galaxies étant trop éloignées pour qu'il soit possible de les résoudre en étoiles individuelles, il faut faire appel à une méthode de synthèse de population pour déterminer quels types d'étoiles les composent. La comparaison de ces populations stellaires avec celles de galaxies non-actives de même type morphologique nous permettra d'en savoir plus sur l'interaction entre la population stellaire et le noyau actif. Dans cette thèse, nous avons développé une nouvelle méthode de synthèse de population stellaire utilisant le flux reçu de la galaxie comme quantité observable à ajuster et tenant compte des continus non stellaires qui diluent le spectre galactique. Nous avons appliqué cette méthode à la galaxie MCG-6-30-15, de type Seyfert 1. Le domaine de longueur d'onde choisi, dans le proche infrarouge, est particulièrement bien adapté pour l'étude de la région interne des galaxies de Seyfert 1 car, contrairement au domaine visible, il est presque totalement dépourvu de raies d'émission provenant du noyau actif. Cependant, il est difficile de constituer une bibliothèque de spectres stellaires complète dans ce domaine de longueur d'onde, en raison d'un déficit d'observations. Or, cette bibliothèque est un constituant essentiel pour la synthèse de population stellaire. Il pourrait être possible de la compléter avec des spectres théoriques, générés à l'aide de modèles d'atmosphères stellaires, mais en comparant ces spectres à des observations dans le proche infrarouge, nous avons constaté un manque de fiabilité des raies d'absorption calculées.
Download or read book CONTRIBUTION A L ETUDE DES ABONDANCES DES POPULATIONS STELLAIRES written by Frédéric Thévenin and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: PRESENTATION DES RESULTATS ET DIFFICULTES RENCONTRES EN ABORDANT LES PROBLEMES D'EVOLUTION DES GALAXIES ET PLUS PRECISEMENT DE LA GALAXIE. UN EXEMPLE D'APPLICATION SUR LES ETOILES NAINES F MONTRE QU'ELLES NE SUBISSENT AUCUNE ANOMALIE D'ABONDANCES EN ELEMENTS LOURDS PAR LA PHYSIQUE PARTICULIERE DE LEURS ATMOSPHERES. LA SPECTROMETRIE A BASSE RESOLUTION ( EQUIV. A 2A) EST ABORDEE. UNE APPLICATION A LA STRUCTURE GALACTIQUE ET A LA PHOTOMETRIE RGU DE BALE EST PRESENTEE. LE SPECTROMETRE MULTIFENTES ESSEFEM QUI REPOND AU BESOIN DE SPECTROGRAPHIE STATISTIQUE EST PRESENTE ET DISCUT
Download or read book Une nouvelle approche pour la synth se de populations stellaires dans les galaxies written by Eduardo Bica and published by . This book was released on 1987 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOUVELLE METHODE POUR LA SYNTHESE DE POPULATIONS STELLAIRES DANS LES NOYAUX DE GALAXIES UTILISANT UNE BIBLIOTHEQUE DE SPECTRES INTEGRES D'AMAS D'ETOILES. L'AVANTAGE DE CETTE METHODE PORTE SUR DEUX PARAMETRES: L'AGE ET LA METALLICITE. UNE ATTENTION SPECIALE A ETE DONNEE AUX DIFFERENTES SOURCES DE ROUGISSEMENT INTERSTELLAIRE AFFECTANT LES AMAS D'ETOILES ET LES GALAXIES. CETTE APPROCHE PERMET UNE ESTIMATION DIRECTE DE L'EVOLUTION CHIMIQUE A PARTIR DU SPECTRE EN ABSORPTION DES NOYAUX DE GALAXIES
Download or read book EVOLUTION SPECTROPHOTOMETRIQUE DES GALAXIES DANS L INFRAROUGE PROCHE SURSAUTS STELLAIRES DANS LES GALAXIES IRAS written by Ariane Lançon and published by . This book was released on 1994 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: CETTE THESE PRESENTE LE DEVELOPPEMENT D'UNE METHODE D'ANALYSE DE SURSAUTS DE FORMATION D'ETOILES ET SON APPLICATION AUX GALAXIES LUMINEUSES DANS L'INFRAROUGE. CES OBJETS, DETECTABLES A DES DISTANCES D'INTERET COSMOLOGIQUE ET SOUVENT IMPLIQUES DANS DES INTERACTIONS, SONT SUSCEPTIBLES DE REPRESENTER DES ETAPES-CLES DE L'EVOLUTION DES GALAXIES. LA METHODE REPOSE SUR LA SYNTHESE EVOLUTIVE DE POPULATIONS STELLAIRES ET DE LEURS PROPRIETES SPECTROPHOTOMETRIQUES INTEGREES, EN PARTICULIER DANS L'INFRAROUGE PROCHE, OU L'EXTINCTION EST RELATIVEMENT FAIBLE ET OU DES SIGNATURES SPECTRALES PHOTOSPHERIQUES (BANDES MOLECULAIRES ET CONTINU) PERMETTENT DE SEPARER LES CONTRIBUTIONS DE POPULATIONS STELLAIRES JEUNES OU EVOLUEES. CES SIGNATURES SONT ETUDIEES D'ABORD EN FONCTION DES PARAMETRES PHYSIQUES DES ETOILES SUR UNE BIBLIOTHEQUE DE 56 SPECTRES STELLAIRES DE REFERENCE ENTRE 1,428 ET 2,5 MICRONS, OBTENUS AU TELESCOPE CANADA-FRANCE-HAWAI PAR SPECTROSCOPIE A TRANSFORMEE DE FOURIER (CHAPITRE 2). LES CHAPITRES 3 ET 4 PRESENTENT LES AMELIORATIONS APPORTEES A UN CODE DE SYNTHESE EVOLUTIVE INITIALEMENT APPLIQUE DANS LE VISIBLE ET L'ULTRAVIOLET, EN VUE DE L'ETUDE D'EPISODES DE FORMATION D'ETOILES VIOLENTS OBSERVES DANS L'INFRAROUGE: INTRODUCTION ET PROLONGEMENT DE NOUVEAUX TRACES D'EVOLUTION STELLAIRE, OPTIMISATION DU CALCUL, MODELISATION COHERENTE DE L'EXTINCTION, DE L'EMISSION DANS L'INFRAROUGE LOINTAIN, DES RAIES DE L'HYDROGENE MOLECULAIRE (2,12 MICRONS) ET DU FER IONISE (1,64 MICRONS), AINSI QUE DES RAIES DE RECOMBINAISON DE L'HYDROGENE ET DE L'HELIUM (2,16 ET 2,06 MICRONS). NOUS INCLUONS LES EFFETS COLLISIONNELS ET LES ECARTS A L'HYPOTHESE OPTIQUEMENT EPAISSE POUR L'HELIUM. APRES L'ETUDE DE 10 SPECTRES DE 1,4 A 2,5 MICRONS DE GALAXIES LUMINEUSES DANS L'INFRAROUGE (CHAPITRE 5), NOUS DETERMINONS AU CHAPITRE 6, A PARTIR DU SPECTRE TYPIQUE DE LA GALAXIE NGC 1614, LES LIMITES SUR LE TAUX DE FORMATION D'ETOILES, L'EXTINCTION, LA FONCTION DE MASSE INITIALE (DEFICIENCE EN ETOILES DE TRES GRANDES ET DE PETITES MASSES). LA PRISE EN COMPTE DE DONNEES SUR L'EXTINCTION DU VISIBLE A L'INFRAROUGE IMPOSE UNE CONTRIBUTION SIGNIFICATIVE DE LA POPULATION EVOLUEE A L'EMISSION ET CONTRAINT LES DISTRIBUTIONS SPATIALES RELATIVES DES DIVERSES COMPOSANTES STELLAIRES ET INTERSTELLAIRES. UNE LIMITE FORTE EST OBTENUE SUR L'EXTINCTION INTERIEURE AUX REGIONS IONISEES. CETTE METHODE PEUT ETRE UTILISEE POUR ETUDIER L'ACTIVITE EN FORMATION D'ETOILES DE GALAXIES PROCHES OU DISTANTES, EN PARTICULIER A PARTIR DES DONNEES QUE FOURNIRONT LE SATELLITE INFRAROUGE INFRARED SPACE OBSERVATORY DE L'AGENCE SPATIALE EUROPEENNE OU LE VERY LARGE TELESCOPE DE L'OBSERVATOIRE EUROPEEN AUSTRAL
Download or read book Populations stellaires des galaxies actives de type Seyfert 2 written by Benoît Joguet and published by . This book was released on 2001 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synth se spectrale de populations stellaires des galaxies written by Sonya Delisle and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colors and populations of galaxies written by and published by . This book was released on 1981 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Report written by Canada-France-Hawaii Telescope Corporation and published by . This book was released on 1988 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The X ray Universe written by Wallace H. Tucker and published by . This book was released on 1985 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beyond the range of optical perception--and of ordinary imaginings--a new and violent universe lay undetected until the advent of space exploration. Supernovae, black holes, quasars and pulsars--these were the secrets of the highenergy world revealed when, for the first time, astronomers attached their instruments to rockets and lofted them beyond the earth's x-ray-absorbing atmosphere. The X-Ray Universe is the story of these explorations and the fantastic new science they brought into being. It is a first-hand account: Riccardo Giacconi is one of the principal pioneers of the field, and Wallace Tucker is a theorist who worked closely with him at many critical periods. The book carries the reader from the early days of the Naval Research Laboratory through the era of V-2 rocketry, Sputnik, and the birth of NASA, to the launching of the Einstein X-Ray Observatory. But this is by no means just a history. Behind the suspenseful, sometimes humorous details of human personality grappling with high technology lies a sophisticated exposition of current cosmology and astrophysics, from the rise and fall of the steady-state theory to the search for the missing mass of the universe.
Download or read book An Introduction to Differential Manifolds written by Jacques Lafontaine and published by Springer. This book was released on 2015-07-29 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an introduction to differential manifolds. It gives solid preliminaries for more advanced topics: Riemannian manifolds, differential topology, Lie theory. It presupposes little background: the reader is only expected to master basic differential calculus, and a little point-set topology. The book covers the main topics of differential geometry: manifolds, tangent space, vector fields, differential forms, Lie groups, and a few more sophisticated topics such as de Rham cohomology, degree theory and the Gauss-Bonnet theorem for surfaces. Its ambition is to give solid foundations. In particular, the introduction of “abstract” notions such as manifolds or differential forms is motivated via questions and examples from mathematics or theoretical physics. More than 150 exercises, some of them easy and classical, some others more sophisticated, will help the beginner as well as the more expert reader. Solutions are provided for most of them. The book should be of interest to various readers: undergraduate and graduate students for a first contact to differential manifolds, mathematicians from other fields and physicists who wish to acquire some feeling about this beautiful theory. The original French text Introduction aux variétés différentielles has been a best-seller in its category in France for many years. Jacques Lafontaine was successively assistant Professor at Paris Diderot University and Professor at the University of Montpellier, where he is presently emeritus. His main research interests are Riemannian and pseudo-Riemannian geometry, including some aspects of mathematical relativity. Besides his personal research articles, he was involved in several textbooks and research monographs.
Download or read book A New Astronomy written by David Peck Todd and published by . This book was released on 1906 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronomy written by P. M. Banks and published by Elsevier. This book was released on 2013-09-24 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aeronomy, Part A is an attempt to make a comprehensive exposition of the processes in aeronomy, the study of composition, movement, and thermal balance of the upper regions of the planetary atmosphere. The text covers topics such as atmospheric regions and atmospheric density, the temperature and molecular mass of the atmosphere; the permanent constituents and the molecular and isotonic composition of the homosphere; and the transition from the homosphere to the heterosphere. Also covered are topics such as the temperature gradient and energies in the thermosphere, conditions at 200km and above 250km, solar radiation and ionization, and aeronomic reactions. The book is recommended for scientists, especially natural physicists, who would like to know more about the field of aeronomy and its advances.
Download or read book All One Universe written by Poul Anderson and published by Macmillan + ORM. This book was released on 1997-05-15 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Poul Anderson himself has put together a retrospective collection of his recent writings, fiction and nonfiction, under the title All One Universe. This is the first major Poul Anderson collection in a decade. It encompasses all his strengths as a teller of tales and, in addition, provides a running commentary in the story notes and in the essays on other literary figures such as Rudyard Kipling, Johannes B. Jensen, and John W. Campbell, Jr., commentary that illuminates the fiction, gives personal insight into the mind of this fine writer, and provides a unifying personality for All One Universe. All One Universe, then, represents the new best of Poul Anderson. It is a rich, varied selection of quintessential science fiction as well as four essays, mostly from recent years, by one of the great science fiction writers of the century. His stories are filled with roaring energy, the soul of poetry, and dark imaginings. At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.
