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Related papers: Disk-Bulge-Halo Models for the Andromeda Galaxy

200 papers

The circumgalactic medium (CGM) surrounding galaxies is believed to be a significant reservoir of baryons, yet its total mass remains poorly constrained. We present a novel approach to probe the CGM of the Andromeda galaxy (M31) using fast…

The last few months have seen the measurements of the radial velocities of all of the dwarf spheroidal companions to the Andromeda galaxy (M31) using the spectrographs (HIRES and LRIS) on the Keck Telescope. This paper summarises the data…

Astrophysics · Physics 2009-10-31 N. W. Evans , M. I. Wilkinson , P. Guhathakurta , E. K. Grebel , S. S. Vogt

We discuss the morphology, photometry and kinematics of the bars which have formed in three N-body simulations. These have initially the same disc and the same halo-to-disc mass ratio, but their haloes have very different central…

Astrophysics · Physics 2009-11-07 E. Athanassoula , A. Misiriotis

We study the neutral hydrogen properties of a sample of 20 bulgeless disk galaxies (Sd - Sdm Hubble types), an interesting class that can be used to constrain galaxy formation and evolution, especially the role of mergers versus internal…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Linda C. Watson , Eva Schinnerer , Paul Martini , Torsten Boeker , Ute Lisenfeld

We present a photometric survey of the stellar halo of the Andromeda galaxy, using Suprime-Cam on the Subaru Telescope. A detailed analysis of VI color-magnitude diagrams of the resolved stellar population is used to measure properties such…

Astrophysics of Galaxies · Physics 2009-12-18 M. Tanaka , M. Chiba , Y. Komiyama , P. Guhathakurta , J. S. Kalirai , M. Iye

We describe a novel framework to model galaxy spectra with two cospatial stellar populations, such as may represent a bulge & bar or thick & thin disc, and apply it to APOGEE spectra in the inner $\sim$2 kpc of M31, as well as to stacked…

We present evidence for a metal-poor, [Fe/H]$\sim-1.4$ $\sigma$=0.2 dex, stellar halo component detectable at radii from 10 kpc to 70 kpc, in our nearest giant spiral neighbor, the Andromeda galaxy. This metal-poor sample underlies the…

Astrophysics · Physics 2008-11-26 S. C. Chapman , R. Ibata , G. F. Lewis , A. M. N. Ferguson , M. Irwin , A. McConnachie , N. Tanvir

M31 has a giant stream of stars extending far to the south and a great deal of other tidal debris in its halo, much of which is thought to be directly associated with the southern stream. We model this structure by means of Bayesian…

Recent observations have revealed that high surface-brightness, metal-rich debris is present over large regions of the Andromeda (M31) stellar halo. We use a set of numerical models to determine whether extended metal-rich debris is…

Stellar kinematics and metallicity are key to exploring formation scenarios for galactic disks and halos. In this work, we characterized the relationship between kinematics and photometric metallicity along the line-of-sight to M31's disk.…

This paper argues that the Milky Way galaxy is probably the largest member of the Local Group. The evidence comes from estimates of the total mass of the Andromeda galaxy (M31) derived from the three dimensional positions and radial…

Astrophysics · Physics 2008-11-26 N. W. Evans , M. I. Wilkinson

We use simulations to study the growth of a pseudobulge in an isolated thin exponential stellar disc embedded in a static spherical halo. We observe a transition from later to earlier morphological types and an increase in bar prominence…

The well-known bar instability of rotationally-supported disk galaxy models has been studied extensively since its first discovery over half a century ago. We were therefore very surprised to find cases of disks embedded in rigid halos,…

Astrophysics of Galaxies · Physics 2025-10-24 J. A. Sellwood , Victor P. Debattista , R. G. Carlberg

We present the discovery of an inhomogenous, low-surface brightness, extended disk-like structure around the Andromeda galaxy (M31) based on a large kinematic survey of more than 2800 stars with the Keck/DEIMOS spectrograph. The stellar…

Astrophysics · Physics 2008-11-26 R. Ibata , S. Chapman , A. M. N. Ferguson , G. Lewis , M. Irwin , N. Tanvir

Abridged: Recent simulations have explored different ways to form accretion disks around low-mass stars. We aim to present observables to differentiate a rotationally supported disk from an infalling rotating envelope toward deeply embedded…

Solar and Stellar Astrophysics · Physics 2015-04-29 Daniel Harsono , Ewine van Dishoeck , Simon Bruderer , Zhi-Yun Li , Jes Jorgensen

We present new mass estimates for Andromeda (M31) using the orbital angular momenta of four satellite galaxies (M33, NGC 185, NGC 147, IC 10) derived from existing proper motions, distances, and line-of-sight velocities. We infer two masses…

Astrophysics of Galaxies · Physics 2023-05-17 Ekta Patel , Kaisey S. Mandel

The central supermassive black hole (SMBH) of the Andromeda galaxy, known as M31*, exhibits dim electromagnetic emission and is inferred to have an extremely low accretion rate for its remarkable mass ($\sim10^8~\rm~M_\odot$). In this work,…

Astrophysics of Galaxies · Physics 2025-07-16 Zhao Su , Zhiyuan Li , Zongnan Li

We provide a set of microlensing optical depth maps for M31. Optical depths towards Andromeda were calculated on the basis of a four component model of the lens and source populations: disk and bulge sources lensed by bulge, M31 halo and…

Astrophysics · Physics 2007-05-23 Geza Gyuk , Arlin Crotts

Using the 100-m radio telescope at Effelsberg, we mapped a large area around the Andromeda Galaxy in the 21-cm line emission of neutral hydrogen to search for high-velocity clouds (HVCs) out to large projected distances in excess of 100…

Astrophysics · Physics 2009-11-13 Tobias Westmeier , Christian Brüns , Jürgen Kerp

We use the adiabatic compression theory to build a physically well - motivated Milky Way mass model in agreement with the observational data. The visible mass of the Galaxy is distributed in a spheroidal bulge and a multi - components disc…

Astrophysics · Physics 2009-11-10 V. F. Cardone , M. Sereno