The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance

  title={The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance},
  author={Jacques R. D. L{\'e}pine and Alexandre Roman-Lopes and Zulema Abraham and Thiago C. Junqueira and Yu. N. Mishurov},
  journal={Monthly Notices of the Royal Astronomical Society},
We present a map of the spiral structure of the Galaxy, as traced by molecular carbon monosulphide (CS) emission associated with IRAS sources which are believed to be compact H ii regions. The CS line velocities are used to determine the kinematic distances of the sources in order to investigate their distribution in the galactic plane. This allows us to use 870 objects to trace the arms, a number larger than that of previous studies based on classical H ii regions. The distance ambiguity of… 

Tracing the Galactic spiral structure with embedded clusters

In the present work we investigate the properties of 18 embedded clusters (ECs). The sample includes 11 previously known clusters and we report the discovery of 7 ECs on WISE images, thus

The observed spiral structure of the Milky Way

Context. The spiral structure of the Milky Way is not yet well determined. The keys to understanding this structure are to increase the number of reliable spiral tracers and to determine their

A new method for estimating the pattern speed of spiral structure in the Milky Way

In the last few decades many eorts have been made to understand the eect of spiral arms on the gas and stellar dynamics in the Milky Way disc. One of the fundamental parameters of the spiral

Kinematics of symmetric Galactic longitudes to probe the spiral arms of the Milky Way with Gaia

We model the effects of the spiral arms of the Milky Way on the disk stellar kinematics in the Gaia observable space. We also estimate the Gaia capabilities of detecting the predicted signatures. We

Overlapping abundance gradients and azimuthal gradients related to the spiral structure of the Galaxy

The connection between some features of the metallicity gradient in the Galactic disc, best revealed by Open Clusters and Cepheids, and the spiral structure, has been explored. The step-like abrupt

Radial migration of the Sun in the Milky Way: a statistical study

The determination of the birth radius of the Sun is important to understand the evolution and consequent disruption of the Sun's birth cluster in the Galaxy. Motivated by this fact, we study the

High Galactic latitude runaway stars as tracers of the spiral arms

A direct observation of the spiral structure of the Galaxy is hindered by our position in the middle of the Galactic plane. We propose a method based on the analysis of the birthplaces of high

Dynamics of the Spiral-Arm Corotation and Its Observable Footprints in the Solar Neighborhood

This article discusses the effects of the spiral-arm corotation on the stellar dynamics in the Solar Neighborhood (SN). All our results presented here rely on: (1) observational evidence that the Sun

Photometric distances to young stars in the inner Galactic disk

We present results of the first extensive and deep CCD photometric survey carried out in the field of the open cluster Trumpler 27, an object in the constellation of Sagittarius not far from the

A new model for gravitational potential perturbations in disks of spiral galaxies. An application to our Galaxy

Aims. We propose a new, more realistic description of the perturbed gravitational potential of spiral galaxies, with spiral arms having Gaussian-shaped groove profiles. The aim is to reach a



Star-forming complexes and the spiral structure of our Galaxy

We have carried out a multiwavelength study of the plane of our Galaxy in order to establish a star-forming-complex catalogue which is as complete as possible. Features observed include H, H109, CO,

Spiral Structure in the Outer Galactic Disk. I. The Third Galactic Quadrant

We combine optical and radio observations to trace the spiral structure in the third quadrant of the Milky Way. The optical observations consist of a large sample of young open clusters and

Direct Determination of the Spiral Pattern Rotation Speed of the Galaxy

The rotation velocity of the spiral pattern of the Galaxy is determined by direct observation of the birthplaces of open clusters of stars in the Galactic disk as a function of their age. Our

The spiral structure of our Milky Way Galaxy

Context. The spiral structure of our Milky Way Galaxy is not yet known. HII regions and giant molecular clouds are the most prominent spiral tracers. Models with 2−4 arms have been proposed to

Spatial distribution of Galactic Hii regions

We present a new, detailed, analysis of the spatial distribution of Galactic H II regions, exploiting a far richer data base than used in previous analyses. Galactocentric distances have been derived

Statistics of young starforming complexes in spiral galaxies using NIR photometry

Aims. Very young stellar clusters and cluster complexes may be embedded in dust lanes along spiral arms in disk galaxies and escape detection in visual bands. Observations in the near-infrared K-band

A new model for the infrared brightness of the Galaxy

We present a model that reproduces the near-infrared brightness distribution of the Galaxy, and we compare its predictions with the results of the Spacelab observations obtained by Kent et al. and

Kinematics of young stars. II. Galactic spiral structure

The young star velocity eld is analysed by means of a galactic model which takes into account solar motion, dierential galactic rotation and spiral arm kinematics. We use two samples of Hipparcos

Globular Cluster System and Milky Way Properties Revisited

Aims. Updated data of the 153 Galactic globular clusters are used to readdress fundamental parameters of the Milky Way, such as the distance of the Sun to the Galactic centre, the bulge and halo

The distance to the center of the Galaxy

For nearly a century astronomers have expended considerable effort to determine the size of the Milky Way. This effort is worthwhile because any change in the value of the distance from the Sun to