Academic literature on the topic 'Galaxies'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Galaxies.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Galaxies"

1

Guhathakurta, P., K. Ing, H. W. Rix, M. Colless, and T. Williams. "Spatially-Resolved Internal Kinematics of 〈z〉 ≈ 0.3 Field Galaxies: Evidence for Rotation." Symposium - International Astronomical Union 171 (1996): 385. http://dx.doi.org/10.1017/s0074180900233044.

Full text
Abstract:
The nature of evolution in faint field galaxies remains a mystery. The Tully-Fisher relation, empirically relating the intrinsic luminosity of a spiral galaxy to its rotation speed, is an important tool for constraining the amount of luminosity evolution in distant field galaxies. Studying the luminosity-vs-linewidth relation for distant galaxies allows one to compare the luminosity of local and distant galaxies. The customary measure of a galaxy's rotation speed is the width of an emission line. It is important, however, to test whether the linewidth is a reliable measure of the galaxy's rotation speed or if it is dominated by turbulent motion within HII regions. In order to do this, we study the spatially-resolved kinematics and distribution of 0[III] gas in about ten 〈B〉∼21 field galaxies at 〈z〉≈0.3.
APA, Harvard, Vancouver, ISO, and other styles
2

Bellovary, Jillian M., Sarra Hayoune, Katheryn Chafla, Donovan Vincent, Alyson Brooks, Charlotte R. Christensen, Ferah D. Munshi, et al. "The origins of off-centre massive black holes in dwarf galaxies." Monthly Notices of the Royal Astronomical Society 505, no. 4 (June 14, 2021): 5129–41. http://dx.doi.org/10.1093/mnras/stab1665.

Full text
Abstract:
ABSTRACT Massive black holes often exist within dwarf galaxies, and both simulations and observations have shown that a substantial fraction of these may be off-centre with respect to their hosts. We trace the evolution of off-centre massive black holes (MBHs) in dwarf galaxies using cosmological hydrodynamical simulations, and show that the reason for off-centre locations is mainly due to galaxy–galaxy mergers. We calculate dynamical time-scales and show that off-centre MBHs are unlikely to sink to their galaxys’ centres within a Hubble time, due to the shape of the hosts’ potential wells and low stellar densities. These wandering MBHs are unlikely to be detected electromagnetically, nor is there a measurable dynamical effect on the galaxy’s stellar population. We conclude that off-centre MBHs may be common in dwarfs, especially if the mass of the MBH is small or the stellar mass of the host galaxy is large. However, detecting them is extremely challenging, because their accretion luminosities are very low and they do not measurably alter the dynamics of their host galaxies.
APA, Harvard, Vancouver, ISO, and other styles
3

Miller, Tim B., and Pieter van Dokkum. "Bayesian Fitting of Multi-Gaussian Expansion Models to Galaxy Images." Astrophysical Journal 923, no. 1 (December 1, 2021): 124. http://dx.doi.org/10.3847/1538-4357/ac2b30.

Full text
Abstract:
Abstract Fitting parameterized models to images of galaxies has become the standard for measuring galaxy morphology. This forward-modeling technique allows one to account for the point-spread function to effectively study semi-resolved galaxies. However, using a specific parameterization for a galaxy’s surface brightness profile can bias measurements if it is not an accurate representation. Furthermore, it can be difficult to assess systematic errors in parameterized profiles. To overcome these issues we employ the Multi-Gaussian expansion (MGE) method of representing a galaxy’s profile together with a Bayesian framework for fitting images. MGE flexibly represents a galaxy’s profile using a series of Gaussians. We introduce a novel Bayesian inference approach that uses pre-rendered Gaussian components, which greatly speeds up computation time and makes it feasible to run the fitting code on large samples of galaxies. We demonstrate our method with a series of validation tests. By injecting galaxies, with properties similar to those observed at z ∼ 1.5, into deep Hubble Space Telescope observations we show that it can accurately recover total fluxes and effective radii of realistic galaxies. Additionally we use degraded images of local galaxies to show that our method can recover realistic galaxy surface brightness and color profiles. Our implementation is available in an open source python package imcascade, which contains all methods needed for the preparation of images, fitting, and analysis of results.
APA, Harvard, Vancouver, ISO, and other styles
4

van Dokkum, Pieter, Zili Shen, Michael A. Keim, Sebastian Trujillo-Gomez, Shany Danieli, Dhruba Dutta Chowdhury, Roberto Abraham, et al. "A trail of dark-matter-free galaxies from a bullet-dwarf collision." Nature 605, no. 7910 (May 18, 2022): 435–39. http://dx.doi.org/10.1038/s41586-022-04665-6.

Full text
Abstract:
AbstractThe ultra-diffuse galaxies DF2 and DF4 in the NGC 1052 group share several unusual properties: they both have large sizes1, rich populations of overluminous and large globular clusters2–6, and very low velocity dispersions that indicate little or no dark matter7–10. It has been suggested that these galaxies were formed in the aftermath of high-velocity collisions of gas-rich galaxies11–13, events that resemble the collision that created the bullet cluster14 but on much smaller scales. The gas separates from the dark matter in the collision and subsequent star formation leads to the formation of one or more dark-matter-free galaxies12. Here we show that the present-day line-of-sight distances and radial velocities of DF2 and DF4 are consistent with their joint formation in the aftermath of a single bullet-dwarf collision, around eight billion years ago. Moreover, we find that DF2 and DF4 are part of an apparent linear substructure of seven to eleven large, low-luminosity objects. We propose that these all originated in the same event, forming a trail of dark-matter-free galaxies that is roughly more than two megaparsecs long and angled 7° ± 2° from the line of sight. We also tentatively identify the highly dark-matter-dominated remnants of the two progenitor galaxies that are expected11 at the leading edges of the trail.
APA, Harvard, Vancouver, ISO, and other styles
5

Ludwig, Eric, Julia Falcone, Mariarosa Marinelli, William Ostling, and Charles T. Liu. "The Relation between Gas-phase Metallicity and Stellar Mass Surface Density in Post-starburst E+A and E+A+ Galaxies within the Coma Cluster Observed by the SDSS-IV MaNGA Survey." Research Notes of the AAS 6, no. 12 (December 8, 2022): 259. http://dx.doi.org/10.3847/2515-5172/aca908.

Full text
Abstract:
Abstract We present an analysis of the Mass–Metallicity Relation (MZR) in 29 post-starburst galaxies in the Coma Cluster. Outward from the central dominant galaxy, NGC 4889, we conducted a conical survey of all galaxies observed by the Sloan Digital Sky Survey Data Release 17 (SDSS DR17) Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey within a 5° radius and redshift constraints 0.013 < z < 0.033. We identified 21 E+A galaxies and 8 “E+A+ galaxies” whose spectra matched the criteria of an E+A galaxy, but contain Balmer emission lines, indicating star formation. We utilized the MaNGA data to calculate each galaxy’s star formation rate densities, gas-phase metallicity and stellar mass. We then compared the MZR between E+A galaxies and E+A+ galaxies to observe how varying star formation rates alter this relation.
APA, Harvard, Vancouver, ISO, and other styles
6

Graham, Alister W. "Resequencing the Hubble sequence and the quadratic (black hole mass)–(spheroid stellar mass) relation for elliptical galaxies." Monthly Notices of the Royal Astronomical Society 522, no. 3 (May 2, 2023): 3588–601. http://dx.doi.org/10.1093/mnras/stad1124.

Full text
Abstract:
ABSTRACT One of the most protracted problems in astronomy has been understanding the evolution of galaxy morphology. Much discussion has surrounded how lenticular galaxies may form a bridging population between elliptical and spiral galaxies. However, with recourse to a galaxy’s central black hole mass, accretion-built spiral galaxies have emerged as the bridging population between low-mass lenticular galaxies and the dusty merger-built lenticular galaxies contiguous with elliptical galaxies and ‘brightest cluster galaxies’ in the black hole/galaxy mass diagram. Spiral galaxies, including the Milky Way, appear built from gas accretion and minor mergers onto what were initially lenticular galaxies. These connections are expressed as a new morphology sequence, dubbed the ‘Triangal’, which subsumes elements of the Hubble sequence and the van den Bergh trident and reveals the bridging nature of the often overlooked ellicular galaxies. Furthermore, a quadratic black hole/galaxy mass relation is found to describe ordinary elliptical galaxies. The relation is roughly parallel to the quadratic-like relations observed for the central spheroidal component of spiral galaxies, dust-rich lenticular galaxies, and old dust-poor lenticular galaxies. The brightest cluster galaxies are offset according to expectations from an additional major merger. The findings have implications for feedback from active galactic nuclei, mapping morphology into simulations, and predicting gravitational wave signals from colliding supermassive black holes. A new galaxy speciation model is presented. It disfavours the ‘monolithic collapse’ scenario for spiral, dusty lenticular, and elliptical galaxies. It reveals substantial orbital angular momentum in the Universe’s first galaxies and unites dwarf and ordinary ‘early-type’ galaxies.
APA, Harvard, Vancouver, ISO, and other styles
7

Douglass, Kelly A., and Regina Demina. "Dependence of the Ratio of Total to Visible Mass on Observable Properties of Sloan Digital Sky Survey MaNGA Galaxies." Astrophysical Journal 925, no. 2 (February 1, 2022): 127. http://dx.doi.org/10.3847/1538-4357/ac3b56.

Full text
Abstract:
Abstract Using spectroscopic observations from the Sloan Digital Sky Survey Mapping Nearby Galaxies at Apache Point Observatory Data Release 15, we study the relationships between the ratio of total to visible mass and various parameters characterizing the evolution and environment of the galaxies in this survey. Measuring the rotation curve with the relative velocities of the Hα emission line across a galaxy’s surface, we estimate each galaxy’s total mass. We develop a statistical model to describe the observed distribution in the ratio of total to visible mass, from which we extract the most probable value of this mass ratio for a given sample of galaxies. We present the relationships between the ratio of total to visible mass and several characteristics describing galactic evolution, such as luminosity, gas-phase metallicity, distance to the nearest neighbor, and position on the color–magnitude diagram. We find that faint galaxies with low metallicities, typically in the blue cloud, have the highest ratios of total to visible mass. This mass ratio is significantly reduced when we include the H i mass in the total visible mass, implying that feedback mechanisms are not as strong in low-mass galaxies as previously thought. Those galaxies that exhibit the second-highest ratios of total to visible mass are the brightest with high metallicities, typically members of the red sequence or green valley. Active galactic nucleus activity is likely both the quenching mechanism and the feedback that drives the mass ratio higher in these massive galaxies. Finally, we introduce a parameterization that predicts a galaxy’s ratio of total to visible mass based only on its photometry and luminosity.
APA, Harvard, Vancouver, ISO, and other styles
8

Camps-Fariña, Artemi, Patricia Sánchez-Blázquez, Santi Roca-Fàbrega, and Sebastián F. Sánchez. "Variable metallicity yields as tracers of inflows." Proceedings of the International Astronomical Union 17, S373 (August 2021): 246–48. http://dx.doi.org/10.1017/s1743921322003982.

Full text
Abstract:
AbstractPristine gas accretion is expected to be the main driver of sustained star formation in galaxies. We measure the required amount of accreted gas at each moment over a galaxy’s history to produce the observed metallicity at that time given its star-forming history. More massive galaxies tend to have higher accretion rates and a larger drop of the accretion rate towards the present time. Within the same mass bin galaxies that are currently star-forming or in the Green Valley have similar, sustained, accretion histories while retired galaxies had a steep decline in the past. Plotting the T80 of the individual accretion histories, a measure of how sustained they are, versus the stellar mass and current sSFR we see a distribution such that currently star-forming galaxies have sustained or recent accretion and retired galaxies have declined accretion histories.
APA, Harvard, Vancouver, ISO, and other styles
9

Jeon, Seyoung, Sukyoung K. Yi, Yohan Dubois, Aeree Chung, Julien Devriendt, San Han, Ryan A. Jackson, Taysun Kimm, Christophe Pichon, and Jinsu Rhee. "Star Formation History and Transition Epoch of Cluster Galaxies Based on the Horizon-AGN Simulation." Astrophysical Journal 941, no. 1 (December 1, 2022): 5. http://dx.doi.org/10.3847/1538-4357/ac9d8c.

Full text
Abstract:
Abstract Cluster galaxies exhibit substantially lower star formation rates than field galaxies today, but it is conceivable that clusters were sites of more active star formation in the early universe. Herein, we present an interpretation of the star formation history (SFH) of group/cluster galaxies based on the large-scale cosmological hydrodynamic simulation, Horizon-AGN. We find that massive galaxies in general have small values of e-folding timescales of star formation decay (i.e., “mass quenching”) regardless of their environment, while low-mass galaxies exhibit prominent environmental dependence. In massive host halos (i.e., clusters), the e-folding timescales of low-mass galaxies are further decreased if they reside in such halos for a longer period of time. This “environmental quenching” trend is consistent with the theoretical expectation from ram pressure stripping. Furthermore, we define a “transition epoch” as where cluster galaxies become less star-forming than field galaxies. The transition epoch of group/cluster galaxies varies according to their stellar and host-cluster halo masses. Low-mass galaxies in massive clusters show the earliest transition epoch of ∼7.6 Gyr ago in lookback time. However, this decreases to ∼5.2 Gyr for massive galaxies in low-mass clusters. Based on our findings, we can describe a cluster galaxy’s SFH with regard to the cluster halo-to-stellar mass ratio.
APA, Harvard, Vancouver, ISO, and other styles
10

Smith, Eric P., and Paul Hintzen. "Multi-Color Imaging of Selected Southern Interacting Galaxies." International Astronomical Union Colloquium 124 (1990): 55–58. http://dx.doi.org/10.1017/s0252921100004887.

Full text
Abstract:
We present preliminary results from a study of selected Arp-Madore Southern Hemisphere peculiar galaxies. Broadband CCD images (BVRI) of a subset of these galaxies allow us to study each galaxy’s optical morphology, color, and (in a crude manner) degree of nuclear activity, and to compare them with similar data we possess on other active galaxies. Many of these galaxies have optical morphologies closely resembling those of powerful radio galaxies (Smith and Heckman 1989), yet their radio emission is unremarkable. Accurate positions for subsequent spectroscopic studies have been determined along with broad band photometry and morphology studies. Detailed observations of these comparatively bright, low-redshift, well-resolved interacting systems should aid our understanding of the role interactions play in triggering galaxy activity. This work is the initial effort in a long term project to study the role played by the dynamics of the interaction in the production and manifestations of activity in galaxies, and the frequency of galaxy mergers.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Galaxies"

1

Brouillet, Nathalie. "Contenu moléculaire de galaxies en interaction : la galaxie spirale Messier 81 et le groupe de galaxies de M81." Bordeaux 1, 1989. http://www.theses.fr/1989BOR10619.

Full text
Abstract:
La distribution et l'abondance du gaz atomique et moleculaire dans les galaxies permettent l'etude de leur histoire et de la formation stellaire. Nous nous sommes interesses a la galaxie spirale messier 81, qui est consideree comme un prototype ideal pour tester la theorie des ondes de densite. Nous avons decouvert la presence d'une emission co dans m81 et une cartographie etendue a revele une deficience moleculaire au centre ainsi qu'une distribution annulaire. Des observations a plus haute resolution spatiale nous ont aussi permis de comparer les distributions relatives du co et d'autres traceurs de bras spiraux. M81 etant le membre principal d'un groupe de galaxies nous avons etudie son interaction gravitationnelle avec ses 2 plus proches compagnons et nous avons cherche a simuler les distributions observees du gaz interstellaire
APA, Harvard, Vancouver, ISO, and other styles
2

Belfort, Patrick. "Proprietes infrarouges et optiques des galaxies iras : des galaxies normales aux galaxies a flambee." Paris 7, 1987. http://www.theses.fr/1987PA077184.

Full text
Abstract:
Grace au satellite iras, on a decouvert un type de galaxies dont le rapport luminosite infrarouge sur bleue peut atteindre 100 ou plus; ces galaxies qu'on suppose subir des flambees de formation d'etoile sont l'objet de cette these. Un modele photometrique simple a ete construit pour rendre compte des proprietes ir lointain et optique de ces galaxies a flambees. La photometrie ccd d'un certain echantillon de galaxies iras a ete realisee pour tester le modele: l'accord modele-observation est satisfaisant et la force, ainsi que l'extinction des flambees ont pu etre estimees
APA, Harvard, Vancouver, ISO, and other styles
3

Belfort, Patrick. "Propriétés infrarouges et optiques des galaxies Iras des galaxies normales aux galaxies à flambée /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37602748s.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Snaith, Owain N. "The environment of galaxies and groups of galaxies." Thesis, University of Central Lancashire, 2011. http://clok.uclan.ac.uk/2931/.

Full text
Abstract:
In this thesis, we employ two numerical tools - semi- analytical models and N-body plus hydrodynamical simulations of large scale structure and individual galaxies - to explore the underlying physics governing the formation and evolution of groups of galaxies, and the role of environment in generating polar structures around disk galaxies. Using phenomenological models of baryonic physics imposed upon large-scale dissipationless simulations of the Universe, semi-analytic models (SAMs) are one of the principal methods used to model large samples of model galaxies. We sought to examine the properties of groups of galaxies with a range of densities using SAMs applied specifically to the industry-standard Millennium Run; for this work, we make use of the well-known Munich and Durham models, and their descendants. We are especially interested in how group properties change as we change the linking length of our Friends- of-Friends group finder. We compare the group populations and richness in these models and compare them both with observations and high-resolution N- body simulations. This leads us to the conclusion that the Durham models produce a much larger population of compact objects than the Munich models. We also explore the group dynamics and morphology as a function of density. We compare the luminosity distributions of galaxy groups using publicly available SAMs in order to explore
APA, Harvard, Vancouver, ISO, and other styles
5

Gruel, Nicolas. "Nature et formation des galaxies : les galaxies compactes lumineuses." Observatoire de Paris, 2002. https://hal.archives-ouvertes.fr/tel-02071406.

Full text
Abstract:
L’évolution de la luminosité infrarouge et de l’UV peut s’expliquer par une chute de la formation stellaire entre les décalages spectraux de 0. 4 à 1, c’est-à-dire depuis 7 à 10 milliards d’années. Cette chute est due à deux types de galaxies : les galaxies infrarouges et les galaxies compactes lumineuses. Au cours de cette thèse, j’ai particulièrement étudié un échantillon de spectres de ces galaxies compactes observées au VLT. Ces objets sont très importants : il y a environ 7 milliards d’années ces galaxies représentaient la population dominante. De plus, malgré leur petite taille, elles rayonnent de l’ordre de 100 fois plus d’énergie que les galaxies locales irrégulières auxquelles les études précédentes les ont assimilées du fait de leurs caractéristiques photométriques et dynamiques semblables. Pour quelques objets, il existe des images prises par le télescope spatial, elles montrent que la plupart de ces galaxies sont en interaction ou du moins possèdent une seconde composante à moins de 10 kpc. L’ensemble des indices réunis que ces objets pourraient être non pas les progéniteurs des galaxies naines compactes locales mais ceux des galaxies spirales
The evolution of the luminosity function in UV is related to the increase in the global star formation rate density up to z ~ 1. This increase is mainly due to two differents types of galaxies : the luminous infrared galaxies (LIRGs) and the luminous compacts galaxies (LCGs). In this thesis, I study a representative sample of LCGs using VLT and HST data at redshift 0. 4-0. 9. About 7 Giga years ago, these galaxies were the dominant galaxy population in number density. Despite their relative small size, they radiate near 100 times more energy than the population of star-forming Blue Compact Galaxies. Spectroscopic analysis show LCGs are composed of a mixed stellar populations, which includes at least : a young burst (less than 10 8 years) superimposed to an older population (more than 1 Giga year). HST images reveal these galaxies are often in interaction or have a multiple component at less than 10 kpc. Our study suggest that these objects may be the progenitors of today’s population of spirals galaxies
APA, Harvard, Vancouver, ISO, and other styles
6

Epinat, Benoit. "Des Galaxies Proches Aux Galaxies Lointaines: Etudes Cinématique et Dynamique." Phd thesis, Université de Provence - Aix-Marseille I, 2008. http://tel.archives-ouvertes.fr/tel-00413769.

Full text
Abstract:
L'étude cinématique des galaxies locales et lointaines permet de contraindre les scénarios de formation et d'évolution des galaxies. Pour cela, la spectroscopie à champ intégral permet une étude détaillée de la cinématique des galaxies proches et fournit depuis peu des indices sur la cinématique des galaxies lointaines. Cette thèse s'appuie principalement sur l'utilisation de l'échantillon cinématique de galaxies locales GHASP. Cet échantillon de référence composé de 203 galaxies spirales et irrégulières de l'Univers local dans des environnements peu denses observées par interférométrie de Fabry-Perot autour de la raie Hα (6563 Å) est le plus grand échantillon de données Fabry-Perot à ce jour. Après un passage en revue des principes de l'interférométrie Fabry-Perot et des nouveautés apportées à la réduction des données Fabry-Perot, mon implication dans le développement du 3D-NTT, nouvel instrument utilisant deux Fabry-Perot est exposée de même que ma participation au projet de spectrographe à grand champ pour les ELT, WFSpec, dont l'objectif est l'étude de l'évolution des galaxies. Je présente dans une deuxième partie les données GHASP. Cet échantillon a été entièrement réduit et analysé à l'aide de nouvelles méthodes. L'analyse cinématique de l'échantillon à partir des cartes cinématiques 2D a été initiée en particulier avec l'étude de la distribution des halos de matière sombre, de la forme des courbes de rotation, de l'influence des potentiels barrés et de la dispersion de vitesses du gaz ionisé. Dans une troisième partie, cet échantillon local sert de point de référence pour l'étude de la cinématique des galaxies lointaines. L'échantillon GHASP est projeté à grand décalage spectral (z = 1.7) afin de déterminer les biais observationnels liés au manque de résolution spatiale des données cinématiques de galaxies lointaines obtenues par SINFONI, OSIRIS et GIRAFFE. L'analyse cinématique de nouvelles observations SINFONI y est également présentée, et l'ensemble des données cinématiques 2D de la littérature est mis en regard avec les résultats obtenus sur l'échantillon GHASP, mettant en évidence une évolution du support dynamique des galaxies avec le temps.
APA, Harvard, Vancouver, ISO, and other styles
7

White, David Allen. "The multiphase medium of elliptical galaxies and clusters of galaxies." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240155.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Epinat, Benoît. "Des galaxies proches aux galaxies lointaines : études cinématique et dynamique." Aix-Marseille 1, 2008. https://tel.archives-ouvertes.fr/tel-00413769v3.

Full text
Abstract:
L’étude cinématique des galaxies locales et lointaines permet de contraindre les scénarios de formation et d’évolution des galaxies. Pour cela, la spectroscopie à champ intégral permet une étude détaillée de la cinématique des galaxies proches et fournit depuis peu des indices sur la cinématique des galaxies lointaines. Cette thèse s’appuie principalement sur l’utilisation de l’échantillon cinématique de galaxies locales GHASP. Cet échantillon de référence composé de 203 galaxies spirales et irrégulières de l’Univers local dans des environnements peu denses observées par interférométrie de Fabry-Perot autour de la raie Ha (6563 Å) est le plus grand échantillon de données Fabry-Perot à ce jour. Après un passage en revue des principes de l’interférométrie Fabry-Perot et des nouveautés apportées à la réduction des données Fabry-Perot, mon implication dans le développement du 3D-NTT, nouvel instrument utilisant deux Fabry-Perot est exposée de même que ma participation au projet de spectrographe à grand champ pour les ELT, WFSpec, dont l’objectif est l’étude de l’évolution des galaxies. Je présente dans une deuxième partie les données GHASP. Cet échantillon a été entièrement réduit et analysé à l’aide de nouvelles méthodes. L’analyse cinématique de l’échantillon à partir des cartes cinématiques 2D a été initiée en particulier avec l’étude de la distribution des halos de matière sombre, de la forme des courbes de rotation, de l’influence des potentiels barrés et de la dispersion de vitesses du gaz ionisé. Dans une troisième partie, cet échantillon local sert de point de référence pour l’étude de la cinématique des galaxies lointaines. L’échantillon GHASP est projeté à grand décalage spectral (z = 1. 7) afin de déterminer les biais observationnels liés au manque de résolution spatiale des données cinématiques de galaxies lointaines obtenues par SINFONI, OSIRIS et GIRAFFE. L’analyse cinématique de nouvelles observations SINFONI y est également présentée, et l’ensemble des données cinématiques 2D de la littérature est mis en regard avec les résultats obtenus sur l’échantillon GHASP, mettant en évidence une évolution du support dynamique des galaxies avec le temps
Kinematical studies of low and high redshift galaxies enables to probe galaxy formation and evolution scenarios. Integral field spectroscopy is a powerful tool to study with accuracy nearby galaxies kinematics. Recent observations also gives a new 2D vision of high redshift galaxies kinematics. This work mostly relies on the kinematical sample of galaxies GHASP. This control sample, composed of 203 local spiral and irregular galaxies in low density environments observed with Fabry-Perot techniques in the Ha line (6563 Å), is by now the largest sample of Fabry-Perot data. After a revue on Fabry-Perot interferometry and a presentation of new data reduction procedures, my implications on both 3D-NTT Fabry-Perot instrument and the wide field spectrograph project (WFSpec) for galaxy evolution study with the european ELT are developed. The second section is dedicated to GHASP data. This sample have been fully reduced and analysed using new methods. The kinematical analysis of 2D kinematical maps has been undertaken with the study of the dark matter distribution, the rotation curves shape, bar signatures and the ionized gas velocity dispersion. In a third section, this local reference sample is used as a zero point for high redshift galaxies kinematical studies. The GHASP sample is projected at high redshift (z = 1. 7) in order to disentangle evolution effects from distance biases in high redshift galaxies kinematical data observed with SINFONI, OSIRIS and GIRAFFE. The kinematical analysis of new SINFONI high redshift observations is also presented and high redshift data found in the literature are compared with GHASP projected sample, suggesting some evolution of the galaxy dynamical support within the ages
APA, Harvard, Vancouver, ISO, and other styles
9

Lima-Neto, Gastao Bierrenbach. "Formation de galaxies elliptiques et structure des amas de galaxies." Paris 7, 1993. http://www.theses.fr/1993PA077317.

Full text
Abstract:
Le theme de cette these est l'etude de la formation et de la structure de galaxies elliptiques au sein de groupes et amas de galaxies. Cette etude se divise selon deux approches principales: l'analyse des proprietes physiques et morphologiques de deux amas de galaxies, abell 85 et 2199 ; et l'etude numerique de la formation de galaxies elliptiques par coalescence de galaxies spirales. Les amas de galaxies ont ete analyses a partir de cliches pris par le detecteur ipc a bord du satellite einstein dans le domaine de rayonnement x. Le gaz intra-amas responsable de l'emission x est suppose etre en equilibre avec le potentiel de l'amas et sert de traceur de ce dernier. En utilisant une technique d'ajustement des cliches par des images de synthese, il est possible de determiner le profil radial de densite du gaz emetteur ainsi que sa morphologie et la presence des sous-structures. En tirant profit des proprietes spectrales du detecteur, le profil de temperature du gaz est estime. L'etude de la formation de galaxies elliptiques se fait par le biais de simulations a n-corps, en utilisant un code en arbre et un code de somme directe sur un ordinateur massivement parallele. Trois classes de conditions initiales ont ete realisees: deux galaxies spirales de masse semblable placees soit en orbite circulaire, soit sur une trajectoire de collision de plein fouet ; des groupes de galaxies spirales en equilibre du viriel ; un effondrement sans collision d'un gaz froid. Les galaxies spirales suivent le modele de miyamoto & nagai a trois composantes bulbe, disque et halo. Les simulations ont ete suivies jusqu'a la formation d'un objet elliptique central en equilibre quasi-stationnaire. Les proprietes physiques et morphologiques de l'objet final des simulations sont confrontees a des modeles issus de la physique statistique appliquee a des systemes gravitationnels en equilibre. Les structures fines, variation de l'ellipticite, deformation et rotation des isocontours, ont ete comparees a des donnees observationnelles. Une modification de la mecanique newtonienne a ete aussi consideree dans le cadre de l'etude de la structure du gaz intra-amas
APA, Harvard, Vancouver, ISO, and other styles
10

Chemin, Laurent. "Cinématique et dynamique de galaxies spirales." Paris 6, 2003. http://www.theses.fr/2003PA066052.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Galaxies"

1

Parcerisa, Josep. Metro: Galàxies metropolitanes = galaxias metropolitanas = metropolitan galaxies. Barcelona: Edicions UPC, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Simon, Seymour. Galaxies. New York: Morrow Junior Books, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Estalella, Robert. Galaxies. Hauppauge, N.Y: Barron's Educational Series, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Consortium, ESNS, ed. Galaxies. London: ILEA Consortium, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Simon, Seymour. Galaxies. New York: Morrow Junior Books, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

World Book, Inc. Galaxies. Chicago: World Book, 2010.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Company, Addison-Wesley Publishing, ed. Galaxies. [Don Mills, ON]: Addison-Wesley Publishers, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Elish, Dan. Galaxies. New York: Marshall Cavendish Benchmark, 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Trammel, Howard K. Galaxies. New York: Children's Press, 2010.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Sipiera, Paul P. Galaxies. New York: Children's Press, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Galaxies"

1

Karttunen, Hannu, Pekka Kröger, Heikki Oja, Markku Poutanen, and Karl Johan Donner. "Galaxies." In Fundamental Astronomy, 347–69. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-662-05333-1_18.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

van der Kruit, P. C., G. A. Tammann, S. d’Odorico, J. Einasto, I. D. Karchentsev, E. Ye Khachikian, J. Lequeux, et al. "Galaxies." In Reports on Astronomy, 293–331. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2981-4_20.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Inglis, Michael David. "Galaxies." In Field Guide to the Deep Sky Objects, 241–92. London: Springer London, 2001. http://dx.doi.org/10.1007/978-1-4471-3680-4_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Karttunen, Hannu, Pekka Kröger, Heikki Oja, Markku Poutanen, and Karl Johan Donner. "Galaxies." In Fundamental Astronomy, 403–28. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-662-11794-1_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Bergeron, Jacqueline. "Galaxies." In Reports on Astronomy, 277–303. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1100-3_20.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

West, Richard M. "Galaxies." In Reports on Astronomy, 313–52. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5392-5_20.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Kitchin, Chris, and Robert W. Forrest. "Galaxies." In Seeing Stars, 113–28. London: Springer London, 1998. http://dx.doi.org/10.1007/978-1-4471-0621-0_9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Parker, Barry. "Galaxies." In Colliding Galaxies, 15–40. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4899-3348-5_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Inglis, Michael. "Galaxies." In The Patrick Moore Practical Astronomy Series, 239–58. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-11644-0_14.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Karttunen, Hannu, Pekka Kröger, Heikki Oja, Markku Poutanen, and Karl Johan Donner. "Galaxies." In Fundamental Astronomy, 387–420. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-53045-0_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Galaxies"

1

Chugunov, I. V., and A. A. Marchuk. "Examination of azimuthally-averaged surface brightness profiles of the spiral arms using decomposition." In 51-st All-Russian with international participation student scientific conference "Physics of Space", 353–56. Ural University Press, 2024. http://dx.doi.org/10.15826/b978-5-7996-3848-1.76.

Full text
Abstract:
We analyze the contribution of spiral arms to the azimuthally-averaged surface brightness profiles of galaxies’ using results of the decomposition of 29 galaxies in the infrared. We show that spiral arms contribution to the galaxy luminosity varies strongly with the galac- tocentric distance. We obtain the characteristic values of the “bump” height on the galaxy’s azimuthally-averaged profile which is caused by the spiral arms. Our results can be applied for the rough estimates of axisymmetric components’ share in galaxy’s light, which is important for determination of disk parameters based on azimuthally-averaged profiles, or for analysis of the spectral energy distribution in galaxy.
APA, Harvard, Vancouver, ISO, and other styles
2

Holanda, João Pedro, Melissa Sales, Marcus Ferraz, and Roney Santos. "Morphological Classification of Galaxies with Different Grayscale Images Using Deep Learning." In Encontro Nacional de Inteligência Artificial e Computacional. Sociedade Brasileira de Computação - SBC, 2023. http://dx.doi.org/10.5753/eniac.2023.234521.

Full text
Abstract:
In recent years, several images of galaxies have been collected by telescopes, so that they could be morphologically analyzed using artificial intelligence devices. Thus, this work aims to analyze new image processing approaches, using grayscale conversion algorithms, in order to explore their influence on CNN (Convolutional Neural Networks). Images from the Galaxies10 DECals dataset of two different types of galaxies were used, which were grayscaled and analyzed separately on the CNN. Aspects such as the influence of redshift and the average pixel value have been studied, since grayscale conversions depend on the influence of each channel. It was concluded that, besides altering the assertiveness of the CNN, the applied grayscales also facilitate recognition by the CNN in specific cases.
APA, Harvard, Vancouver, ISO, and other styles
3

Blain, Andrew W. "Infrared galaxies." In COSMO--98. ASCE, 1999. http://dx.doi.org/10.1063/1.59389.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Wyse, Rosemary F. G. "Normal galaxies." In Astrophysics from the Moon. AIP, 1990. http://dx.doi.org/10.1063/1.39329.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Putman, Mary E., Jana Grcevich, J. E. G. Peek, Robert Minchin, and Emmanuel Momjian. "Feeding Galaxies." In THE EVOLUTION OF GALAXIES THROUGH THE NEUTRAL HYDROGEN WINDOW. AIP, 2008. http://dx.doi.org/10.1063/1.2973567.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Muxlow, Tom W. B., R. J. Beswick, Anita Richards, and H. J. Thrall. "Starburst galaxies." In 8th European VLBI Network Symposium. Trieste, Italy: Sissa Medialab, 2007. http://dx.doi.org/10.22323/1.036.0031.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Sparks, William B. "Plasmas in Galaxies: Ionized Gas in Elliptical Galaxies." In PLASMAS IN THE LABORATORY AND IN THE UNIVERSE: New Insights and New Challenges. AIP, 2004. http://dx.doi.org/10.1063/1.1718470.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Järvelä, Emilia, Anne Lähteenmäki, and Marco Berton. "Host galaxies of jetted narrow-line Seyfert 1 galaxies." In Revisiting narrow-line Seyfert 1 galaxies and their place in the Universe. Trieste, Italy: Sissa Medialab, 2018. http://dx.doi.org/10.22323/1.328.0046.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Zasov, A., A. Khoperskov, N. Zaitseva, and S. Khrapov. "When dwarf galaxies turn to be spiral?" In ASTRONOMY AT THE EPOCH OF MULTIMESSENGER STUDIES. Proceedings of the VAK-2021 conference, Aug 23–28, 2021. Crossref, 2022. http://dx.doi.org/10.51194/vak2021.2022.1.1.173.

Full text
Abstract:
Spiral structure is rarely observed in dwarf galaxies because the formation of spiral arms requires special conditions. Weanalyze the sample of about 40 dS-galaxies found among the bright late-type galaxies with M B > −18 m and photometricdiameter D 25 < 12 kpc. These galaxies do not differ statistically from non-dS galaxies apart from the lower average gas (HI)fraction. To check the conditions of formation of spiral structure we carried out a series of direct N-body/hydrodynamicsimulations of dynamic evolution of low-mass stellar/gaseous discs varying the initial parameters of galaxies. We came toconclusion that the gravitational mechanism of formation of spiral structure is effective only for thin stellar/gaseous discs,non-typical for dwarf galaxies. The thicker stellar disc, the more gas is required for the spiral structure to form. The reducedgas content in most dS-galaxies may be a result of more efficient star formation in their relatively thin discs.
APA, Harvard, Vancouver, ISO, and other styles
10

Takagi, T. "Silicate-break galaxies." In THE SPECTRAL ENERGY DISTRIBUTIONS OF GAS-RICH GALAXIES: Confronting Models with Data; International Workshop. AIP, 2005. http://dx.doi.org/10.1063/1.1913947.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Galaxies"

1

España Fontán, Paula, and Maria Angeles Gomez Flechoso. Effects of the orbit orientation on the evolution of dwarf satellite galaxies. Fundación Avanza, May 2023. http://dx.doi.org/10.60096/fundacionavanza/2492022.

Full text
Abstract:
Cosmological models propose a hierarchical scenario for galaxy evolution, where dwarf galaxies are accreted in the halo of larger ones. We study the effect of the satellite’s orbital orientation on the planar alignment of satellite galaxies.
APA, Harvard, Vancouver, ISO, and other styles
2

Dey, A., J. Shields, and W. Van Breugel. Radio loud far-infrared galaxies. Office of Scientific and Technical Information (OSTI), March 1990. http://dx.doi.org/10.2172/6850837.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Избрехт, А. Р. COSMOLOGICAL REDSHIFT OF GALAXIES’ SPECTRA. DOI СODE, 2015. http://dx.doi.org/10.18411/doicode-2023.162.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Blanton, Elizabeth L., T. E. Clarke, Craig L. Sarazin, Scott W. Randall, and Brian R. McNamara. AGN Feedback in Clusters of Galaxies. Fort Belvoir, VA: Defense Technical Information Center, January 2010. http://dx.doi.org/10.21236/ada520956.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Medoff, Jonah, Alex Drlica-Wagner, Burçin Mutlu-Pakdil, and Jeff Carlin. Detecting Dwarf Galaxies Around NGC 55. Office of Scientific and Technical Information (OSTI), November 2023. http://dx.doi.org/10.2172/2212418.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Springmann, Alessondra. Host Galaxies of X-Shaped Radio Sources. Office of Scientific and Technical Information (OSTI), September 2006. http://dx.doi.org/10.2172/892607.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Leung, Y., Y. Zhang, B. Yanny, K. Herner, J. Annis, A. Palmese, A. Sampaio-Santos, et al. The Diffuse Light Envelope of Luminous Red Galaxies. Office of Scientific and Technical Information (OSTI), May 2020. http://dx.doi.org/10.2172/1637638.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Rykoff, E. S. The L_X-M relation of Clusters of Galaxies. Office of Scientific and Technical Information (OSTI), May 2008. http://dx.doi.org/10.2172/928354.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Smullen, Rachel, and Soumi De. Black Holes, Crashing Galaxies, and Strange New Planets. Office of Scientific and Technical Information (OSTI), June 2021. http://dx.doi.org/10.2172/1787271.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Behroozi, Peter. Using Cumulative Number Densities to Compare Galaxies Across Cosmic Time. Office of Scientific and Technical Information (OSTI), October 2013. http://dx.doi.org/10.2172/1095532.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography