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[en] This is an introductory paper to theoretical and experimental gravitational wave research. In the first part, we give the precise mathematical description of a weak gravitational wave in the general framework of metric theories. Then we discuss the effect of these waves on material systems and the principle of the present detectors. The third part concerns the generation of gravitational radiations and reviews the possible astrophysical sources. Finally, we discuss the limitations and the state of the art of present detectors
Journal
Annales de Physique (Paris); ISSN 0003-4169; 
; v. 10(3); p. 201-218
; v. 10(3); p. 201-218
[en] We study a one arm pendular Fabry-Perot interferometer with specifications corresponding to the two arms interferometers designed to detect gravitational radiation. We consider the non linearities originating from the radiation force and the effects of time delays due to the finite length of the arm. We derive the exact and the associated ''predictivised'' equations for the motion of the suspended mirror. We show that effects of time delays increase considerably the stability of the device when the optical relaxation time is of the order of the period of the pendulum, a case of relevance when light is recycled. However the thermal noise does not seem to be much modified when calculated within a simple approximation scheme
Journal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 10(3); p. 241-252
; v. 10(3); p. 241-252
[en] A review is made on the results concerning the stellar populations in the central region of the galaxies
[fr]
Il est presente une revue des resultats obtenus sur les populations stellaires dans les regions centrales des galaxiesJournal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 4(2); p. 147-149
; v. 4(2); p. 147-149
[en] There is to-day a general agreement to consider General Relativity as the most efficient theory to describe the observational data in cosmology. In particular, Friedmann's Models offer good interpretation of the Hubble's Law and of the 30K cosmic radiation considered as the present residual energetic effect to the big bang. To-day cosmologists begin to study the energetic component of the universe, while, during the past years, only its material component was taken in account. The study of the early universe is now approaching the primeval explosion. At this knowledge level, the fondamental structures of our mind are reflected upon the object of their studies and there exists a parallel between the physical universe and the mathematical universe of the sets
[fr]
Actuellement la plupart des astrophysiciens s'accordent a reconnaitre que la theorie de la Relativite Generale reste celle qui regroupe le plus de faits observationnels relatifs a la cosmologie. Les modeles de Friedmann en particulier rendent bien compte de la loi de Hubble et de la loi du refroidissement energetique qui conduit aujourd'hui a l'observation d'un rayonnement cosmique de 30K. Apres etre restee longtemps l'etude de la seule composante materielle de l'univers, la cosmologie aborde aujourd'hui l'etude de sa composante energetique, remontant le passe de l'univers jusqu'a l'approche de son explosion primordiale. A ce niveau de connaissance, les structures de la raison se projettent sur leur objet et un parallele se dessine entre l'univers physique et l'univers mathematique des ensemblesJournal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 4(2); p. 209-212
; v. 4(2); p. 209-212
[en] The basic ideas of the model microfield method are shortly reviewed. Recent applications to the broadening of the alkali metal resonance lines, of hydrogen lines and of overlapping helium lines are presented. Some approximations are discussed with special emphasis on the problem of the ion dynamics
[fr]
Les idees de base de la methode du microchamp modele sont brievement rappelees. Des applications recentes a l'elargissement des raies de resonance des metaux alcalins, de l'hydrogene et des raies d'helium a composante interdite sont presentees. On discute de quelques approximations en mettant particulierement l'accent sur le probleme de la dynamique des ionsJournal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 5(4); p. 219-226
; v. 5(4); p. 219-226
[en] The main laser-induced collisional ionization processes are examined according to the shape and the relative position of the input and output channel potential curves. The different cases are illustrated by a few systems under experimental investigation, with emphasis on beam experiments
Journal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 9(4); p. 647-656
; v. 9(4); p. 647-656
[en] The present role of Quantum Chemistry in the field of interstellar molecules is illustrated by structure and reactivity studies concerning the (CS + H)+, (SiO + H)+, (SiS + H)+ systems
Journal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 9(4); p. 617-620
; v. 9(4); p. 617-620
[en] In this extragalactic workshop, it is necessary to keep in mind that a large number of extragalactic researches rest on a very precarious observational galactic basis: first, the intrinsic luminosity calibration is presently based on a very small number of accurate data; second, there is no statistically correct representation of the solar neighourhood. The European astrometric satellite project Hipparcos offers a solution able to bring a fundamental improvement to this situation: trigonometric parallax (and therefore absolute magnitude) and proper motion survey of all stars brighter than apparent magnitude 9 (60000 stars) and observation of 40000 stars with magnitude between 9 and 14, and this with a very high accuracy and a perfect homogeneity
[fr]
Dans le cadre de ces journees extragalactiques sol-espace, il convient de rappeler que beaucoup de recherches extragalactiques reposent sur une galactique observationnelle tres precaire: d'une part, la calibration des luminosites intrinseques est actuellement basee sur un nombre tres restreint de donnees precises; d'autre part nous ne disposons pas d'une representation statistique correcte du voisinage solaire. Le projet de satellite astrometrique europeen HIPPARCOS propose une solution capable d'ameliorer de maniere fondamentale cette situation: survey en parallaxe trigonometrique (donc en magnitude absolue) et en mouvement propre de toutes les etoiles jusqu'a la magnitude apparente 9 (60000 etoiles) et mesures de 40000 etoiles de magnitude comprise entre 9 et 14, et ceci avec une tres grande precision et une homogeneite parfaiteJournal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 4(2); p. 163-165
; v. 4(2); p. 163-165
[en] A bidimensional classification for galaxies with active nuclei (N galaxies, Seyfert galaxies, quasars and BL Lac objects) based on a morphological and a spectroscopic criteria is proposed. It is suggested that a quasaar or an N galaxy should be called a Seyfert 1 if their spectrum shows broad Balmer lines; that an extragalatic star-like object should be called a quasar, even if it is has the spectrum of an BL Lac object, etc
[fr]
On propose une classification bidimensionnelle des galaxies a noyau actif (galaxies N, galaxies de Seyfert, objets de type BL Lacertae et quasars), basee sur un critere morphologique et un critere spectroscopique. On suggere qu'un quasar ou une galaxie N doivent etre baptises galaxie de Seyfert de type 1 si leur spectre presente des raies de Balmer larges en emission; qu'un objet extragalactique d'aspect stellaire doit etre appele quasar meme si son spectre est celui d'un objet de type BL Lac, etcJournal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 4(2); p. 197-203
; v. 4(2); p. 197-203
[en] The manner in which laser spectroscopic techniques can be use to probe collisional processes in atomic vapors is reviewed. A discussion of the saturation spectroscopy of three-level systems, coherent transient spectroscopy, and a beam-laser spectroscopy system is presented. It is shown that such experiments can provide useful information on both the total and differential cross sections for atom-atom scattering
Journal
Annales de Physique (Paris); ISSN 0003-4169; ; v. 5(4); p. 199-206
; v. 5(4); p. 199-206
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