Unveiling the Boxy Bulge and Bar of the Andromeda Spiral Galaxy

  title={Unveiling the Boxy Bulge and Bar of the Andromeda Spiral Galaxy},
  author={Rachael L. Beaton and Steven R. Majewski and Puragra Guhathakurta and Michael F. Skrutskie and Roc M. Cutri and John Good and Richard J. Patterson and E. Athanassoula and Martin Bureau},
  journal={The Astrophysical Journal Letters},
  pages={L91 - L94}
A new, 2.8 deg2 J, H, Ks near-infrared (NIR) survey from the 2MASS 6X program across the extent of the optical disk of the Andromeda (M31) galaxy provides a clear view of the M31 center almost completely unfettered by dust extinction and reveals a high-contrast bulge with very boxy isophotes dominating the NIR light to a semimajor axis of ~700'' (2.6 kpc). The inner bulge (≲50'') isophotes are relatively circular but show some twisting. Beyond this, (1) the M31 bulge ellipticity increases, (2… 

M31* and its circumnuclear environment

We present a multiwavelength investigation of the circumnuclear environment of the Andromeda galaxy (M31), utilizing archival Chandra, FUSE, GALEX, HST and Spitzer data as well as ground-based

The star formation history in the M31 bulge

We present the study of stellar populations in the central 5.5' (~1.2 kpc) of the M31 bulge by using the optical color magnitude diagram derived from HST ACS WFC/HRC observations. In order to enhance

A revised Λ CDM mass model for the Andromeda Galaxy

We present an updated mass model for M31 that makes use of a Spitzer 3.6-μm image, a mass-to-light ratio gradient based on the galaxy's B - R colour profile, and observed rotation curve data from a

The extended disc and halo of the Andromeda galaxy observed with Spitzer-IRAC

We present the first results from an extended survey of the Andromeda galaxy (M31) using 41.1 h of observations by Spitzer-IRAC at 3.6 and 4.5 µm. This survey extends previous observations to the

An almost head-on collision as the origin of two off-centre rings in the Andromeda galaxy

Numerical simulations indicate that both rings result from a companion galaxy plunging through the centre of the disk of M31, the closest spiral galaxy to the Milky Way, and the most likely interloper is M32.

Stellar populations of the central region of M 31

Aims. We continue the analysis of the data set of our spectroscopic observation campaign of M 31, whose ultimate goal is to provide an understanding of the three-dimensional structure of the bulge,

Evidence for non-axisymmetry in M31 from wide-field kinematics of stars and gas

As the nearest large spiral galaxy, M31 provides a unique opportunity to learn about the structure and evolutionary history of this galaxy type in great detail. Among the many observing programs

The Herschel exploitation of local galaxy andromeda (HELGA): IV. Dust scaling relations at sub-kpc resolution

Context. Dust and stars play a complex game of interactions in the interstellar medium and around young stars. The imprints of these processes are visible in scaling relations between stellar

The Herschel Exploitation of Local Galaxy Andromeda (HELGA) - I. Global far-infrared and sub-mm morphology

We have obtained Herschel images at five wavelengths from 100 to 500 micron of a ~5.5x2.5 degree area centred on the local galaxy M31 (Andromeda), our nearest neighbour spiral galaxy, as part of the


We have constructed an extended composite luminosity profile for the Andromeda galaxy, M31, and have decomposed it into three basic luminous structural components: a bulge, a disk, and a halo. The



Unravelling the mystery of the M31 bar

The inclination of M31 is too close to edge-on for a bar component to be easily recognized and is not sufficiently edge-on for a boxy/peanut bulge to protrude clearly out of the equatorial plane.

The photometric structure of the inner Galaxy

The light distribution in the inner few kiloparsecs of the Milky Way is recovered non­ parametrically from a dust-corrected near-infrared COBEIDIRBE surface brightness map of the inner Galaxy. The

COBE diffuse infrared background experiment observations of the galactic bulge

Low angular resolution maps of the Galactic bulge at 1.25, 2.2, 3.5, and 4.9 micrometers obtained by the Diffuse Infrared Background Experiment (DIRBE) onboard NASA's Cosmic Background Explorer

Improving the triaxial bulge model of M31

A detailed hydrodynamical model of the gas flow in the triaxial gravitational potential of the bulge of the Andromeda galaxy (M31) has recently been proposed by Berman, and shown to provide excellent

Spiral arms, bar shape and bulge microlensing in the Milky Way

A new model for the luminosity distribution in the inner Milky Way is found, using a non-parametric penalized maximum-likelihood algorithm to deproject a dereddened COBE/ DIRBE L-band map of the

Hydrodynamic simulations of the triaxial bulge of M 31

The interstellar gas flow in the inner disk of M 31 is modelled using a new, two dimensional, grid based, hydrodynamics code. The potential of the stellar bulge is derived from its surface brightness

K-band observations of boxy bulges – I. Morphology and surface brightness profiles

Kn-band images, unsharp-masked images, as well as major-axis and vertically- summed surface brightness profiles are presented for 30 edge-on spiral galaxies, most with a boxy or peanut-shaped (B/PS)

The Stellar bar in NGC 1068

High-resolution 2-micron mapping of the inner disk of NGC 1068 reveals a bar extending to + or - 16 arcsec from the nucleus at position angle 48 deg. The stellar mass distribution, presumably traced

On the nature of bulges in general and of box/peanut bulges in particular: input from N-body simulations

Objects designated as bulges in disc galaxies do not form a homogeneous class. I distinguish three types: the classical bulges, the properties of which are similar to those of ellipticals and which

Erratum - the Photometric Properties of Box / Peanut Galactic Bulges

Optical and near-IR photometry is presented for a sample of 14 edge-on galaxies displaying «box/peanut» bulge structure. The observed luminosity distributions are modelled using a 2D non-linear,