English
Related papers

Related papers: Distribution functions for evolved stars in the in…

200 papers

Many of the stars in the Galaxy were formed in binary systems. The widest of these can eventually become disrupted due to a combination of kicks from passing stars and the Galactic tidal field. If the Galactic disk were purely axisymmetric,…

Astrophysics of Galaxies · Physics 2024-07-11 Tomer D. Yavetz

The velocity distribution of neighbouring stars is deduced from the Hipparcos proper motions. We have used a classical Schwarzschild decomposition and also developed a dynamical model for quasi-exponential stellar discs. This model is a 3-D…

Astrophysics · Physics 2007-05-23 O. Bienaymé

The exponential profile has long been hypothesized as the fundamental morphology of galactic disks. The IllustrisTNG simulations reproduce diverse surface-density profiles: Type I (single exponential), Type II (down-bending), and Type III…

Astrophysics of Galaxies · Physics 2026-04-30 Liufei Chen , Min Du , Shuai Lu , Jing Li , Luis C. Ho

We present here a self-consistent, tridimensional model of a disc galaxy composed by a number of ellipsoidal distributions of matter having different flattening and density profile. The model is self-consistent and takes into account the…

Astrophysics · Physics 2009-09-25 E. Pignatelli , G. Galletta

The presence of young stars, aged around several million years and situated within the range of $\sim 0.04-1$ pc from our Galactic center raises a question about their origins and dynamical evolutions. Their kinematics provide an…

Astrophysics of Galaxies · Physics 2024-04-29 Xiao Fan , Qingwen Wu , Jiancheng Wu , Xiangli Lei , Mengye Wang , Fulin Li

The color-magnitude diagram of $ \sim 3 \times 10^5 $ stars obtained for Baade's Window towards the Galactic bulge with the OGLE project reveals a surprisingly narrow main sequence due to galactic disk stars at a distance of $d \sim 2 $…

Astrophysics · Physics 2009-10-22 B. Paczynski , K. Z. Stanek , A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak , M. Mateo

An accelerated logarithmic potential models the mean motion of stars in a flat rotation curve galaxy that sustains a wind system. For stars outside the galactic wind launching region, the asymmetric removal of linear momentum by the wind is…

Astrophysics · Physics 2009-11-13 Fathi Namouni , Massimiliano Guzzo , Elena Lega

Context. Dynamically self-consistent galactic models are necessary for analysing and interpreting star counts, stellar density distributions, and stellar kinematics in order to understand the formation and the evolution of our Galaxy. Aims.…

Astrophysics of Galaxies · Physics 2018-12-12 Olivier Bienaymé , Jérome Leca , Annie C. Robin

We present an approach to the design of distribution functions that depend on the phase-space coordinates through the action integrals. The approach makes it easy to construct a dynamical model of a given stellar component. We illustrate…

Astrophysics of Galaxies · Physics 2015-06-23 Lorenzo Posti , James Binney , Carlo Nipoti , Luca Ciotti

We present a family of spherical models for elliptical galaxies and bulges consisting of a stellar component and a central black hole. All models in this family share the same stellar density profile, which has a steep central cusp. The…

Astrophysics · Physics 2009-11-10 Maarten Baes , Herwig Dejonghe

Young massive stars in the central parsec of our Galaxy are best explained by star formation within at least one, and possibly two, massive self-gravitating gaseous discs. With help of numerical simulations, we here consider whether the…

Astrophysics · Physics 2009-11-13 Alexander Hobbs , Sergei Nayakshin

An extension of Schwarzschild's galaxy-building technique is presented that, for the first time, enables one to build Schwarzschild models with known distribution functions (DFs). The new extension makes it possible to combine a DF that…

Astrophysics · Physics 2009-10-31 Ralf M. Hafner , N. Wyn Evans , Walter Dehnen , James Binney

Diffuse interstellar bands (DIBs) are absorption features seen in optical and infrared spectra of stars that are probably caused by large and complex molecules in the ISM. Here we investigate the Galactic distribution and properties of two…

In a series of papers we study the stellar dynamics of the grand design barred-spiral galaxy NGC~1300. In the first paper of this series we estimate the gravitational potential and we give it in a form suitable to be used in dynamical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 C. Kalapotharakos , P. A. Patsis , P. Grosbol

We present an analysis of high latitude $\delta$ Scuti stars ($\left|b\right|> 1^{\circ}$) in the Galactic bulge region ($-8^{\circ}.3< l<9^{\circ}.4$) using a clean sample of the photometric data of $7,440$ stars recently released by the…

Astrophysics of Galaxies · Physics 2022-08-30 Mami Deka , Sukanta Deb , Kerdaris Kurbah

Sensitive ground-based submillimeter surveys, such as ATLASGAL, provide a global view on the distribution of cold dense gas in the Galactic plane. Here we use the 353 GHz maps from the Planck/HFI instrument to complement the ground-based…

Solar and Stellar Astrophysics · Physics 2016-01-13 T. Csengeri , A. Weiss , F. Wyrowski , K. M. Menten , J. S. Urquhart , S. Leurini , F. Schuller , H. Beuther , S. Bontemps , L. Bronfman , Th. Henning , N. Schneider

We present a method for constructing dynamical models of stellar systems described by distribution functions and constrained by discrete-kinematic data. We implement various improvements compared to earlier applications of this approach,…

Astrophysics of Galaxies · Physics 2026-04-28 Eugene Vasiliev , Anja Feldmeier-Krause , Mattia C. Sormani

An analysis of high-resolution near-infrared spectra of a sample of 45 asymptotic giant branch (AGB) stars towards the Galactic bulge is presented. The sample consists of two subsamples, a larger one in the inner and intermediate bulge, and…

Solar and Stellar Astrophysics · Physics 2016-08-08 S. Uttenthaler , J. A. D. L. Blommaert , P. R. Wood , T. Lebzelter , B. Aringer , M. Schultheis , N. Ryde

We present detailed three-dimensional modelling of the stellar luminosity distribution for the disks of 31 relatively nearby (<= 110 Mpc) edge-on spiral galaxies. In contrast to most of the standard methods available in the literature we…

Astrophysics · Physics 2009-10-31 M. Pohlen , R. -J. Dettmar , R. Luetticke , U. Schwarzkopf

Analytic distribution functions (DFs) for the Galactic disc are discussed. The DFs depend on action variables and their predictions for observable quantities are explored under the assumption that the motion perpendicular to the Galactic…

Astrophysics of Galaxies · Physics 2015-05-14 James Binney