Galactic spiral structure
@article{Francis2009GalacticSS, title={Galactic spiral structure}, author={Charles Francis and Erik Anderson}, journal={Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences}, year={2009}, volume={465}, pages={3425 - 3446} }
We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars belong to one of these streams. The results of our investigation have led us to re-examine the hydrogen maps of the Milky Way, from which we identify the possibility of a symmetric two-armed spiral with half the conventionally accepted pitch angle. We describe…
Figures from this paper
21 Citations
Indications of an Unmodelled Component in Spectrographic Measurements of Local Stars
- Physics
- 2009
Context: While CDM models and MOND give explanations for flat rotation curves of other galaxies, both present observational problems and the local gradient of the Milky Way's rotation curve is not…
A Synthesis of Fundamental Parameters of Spiral Arms, Based on Recent Observations in the Milky Way
- Physics
- 2013
Recent advances in the
position and shape of each spiral arm in the Milky Way (pitch angle, shape,
number, inter-arm separation
at the Sun) are evaluated and compared, and a statistical analysis…
Peculiarities of galactic rotation in the solar neighborhood from the data on red clump giants
- Physics
- 2008
The three-dimensional Ogorodnikov-Milne model was used to investigate the local velocity field on the basis of the tangential velocities of more than 53 000 red giants which were identified as most…
The Lin–Shu type density wave structure of our Galaxy: line-of-sight velocities of 396 HII regions
- Physics
- 2015
In this fifth paper in a series, we check again the Lin–Shu idea of small-amplitude density waves in our Galaxy. The updated catalogue of Galactic objects of Hou and Han (Hou and Han in Astron…
Chemically tagging the Hyades Supercluster - A homogeneous sample of F6-K4 kinematically selected northern stars
- Physics
- 2012
Stellar kinematic groups are kinematical coherent groups of stars that might have a common origin. These groups are dispersed throughout the Galaxy over time by the tidal effects of both Galactic…
Chemical tagging of the Ursa Major moving group: A northern selection of FGK stars
- Physics
- 2014
Stellar kinematic groups are kinematical coherent groups of stars which might share a common origin.These groups spread through the Galaxy over time due to tidal effects caused by Galactic rotation…
Quantifying the contamination by old main-sequence stars in young moving groups: the case of the Local Association
- Physics, Geology
- 2009
Context. The associations and moving groups of young stars are excellent laboratories for investigating stellar formation in the solar neighborhood. Previous results have confirmed that a…
Calibration of RAVE distances to a large sample of Hipparcos stars
- Physics
- 2013
A magnitude limited population of 18 808 Hipparcos stars is used to calibrate distances for 52 794 RAVE stars, including dwarfs, giants, and pre-main sequence stars. I give treatments for a number of…
Spin: Ubiquitous, Fundamental, Purposeful: Its Complementary Interactions with Gravity
- Physics
- 2020
In a prior article we explained how axial spin of celestial bodies interact with mutual gravitation in the phenomenon of synchronous rotation of our moon and the major moons of the gas giants. We…
Stars and substars nearest to the Sun: A study review
- Physics
- 2013
The structure of the solar neighborhood and its position in the galaxy, including the galactocentric distances, are analyzed. Catalogues are examined of near-sun stars and substars, which are…
References
SHOWING 1-10 OF 43 REFERENCES
Star-forming complexes and the spiral structure of our Galaxy
- Physics
- 2003
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,…
The Distribution of Nearby Stars in Velocity Space Inferred from HIPPARCOS Data
- Physics
- 1998
The velocity distribution f(v) of nearby stars is estimated, via a maximum likelihood algorithm, from the positions and tangential velocities of a kinematically unbiased sample of 14,369 stars…
The stellar velocity distribution in the solar neighbourhood
- Physics, Geology
- 2003
We explore the heating of the velocity distribution in the solar neighbourhood by stochastic spiral waves. Our investigation is based on direct numerical integration of initially circular…
Sinfoni in the galactic center : Young stars and infrared flares in the central light-month
- Physics
- 2005
We report on 75 mas resolution, near-IR imaging spectroscopy within the central 30 lt-days of the Galactic center, taken with the new adaptive optics-assisted integral-field spectrometer SINFONI on…
The distribution of nearby stars in phase space mapped by Hipparcos II. Inhomogeneities among A-F type stars
- Physics
- 1998
A volume limited and absolute magnitude limited sample of A-F type dwarfs within 125 parsecs of the Sun is searched for inhomogeneities in the density- velocity space, expecting signatures of the…
The spiral structure of our Milky Way Galaxy
- Physics
- 2009
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…
The distribution of nearby stars in phase space mapped by Hipparcos - III. Clustering and streaming among A-F type stars
- Physics
- 1998
This paper presents the detailed results obtained in the search of density-velocity inhomogeneities in a volume limited and absolute magnitude limited sample of A-F type dwarfs within 125 parsecs of…
The Geneva–Copenhagen Survey of the Solar Neighbourhood
- Physics, GeologyPublications of the Astronomical Society of Australia
- 2004
Abstract We report on a new survey of metallicities, ages, and Galactic orbits for a complete, magnitude-limited, and kinematically unbiased all-sky sample of 16 682 nearby F- and G-dwarfs. Our ∼ 63…
The saturation of disk heating in the solar neighborhood and evidence for a merger 9 Gyrs ago
- Physics, Geology
- 2000
We re-examine the age-velocity dispersion relation in the solar neighborhood using improved stellar age estimates that are based on Hipparcos parallaxes and recent stellar evolution calculations. The…
Globular Cluster System and Milky Way Properties Revisited
- Physics
- 2006
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…