2012MNRAS.422.1283F


C.D.S. - SIMBAD4 rel 1.7 - 2019.10.21CEST18:38:42

2012MNRAS.422.1283F - Mon. Not. R. Astron. Soc., 422, 1283-1293 (2012/May-2)

Evidence of a bisymmetric spiral in the Milky way.

FRANCIS C. and ANDERSON E.

Abstract (from CDS):

It is extremely difficult to observe the spiral structure of the Milky Way because of our viewing point within the Galactic disc. The aims of this paper are to clarify the structure of the Galaxy by re-examination of gas distributions and data from the Two Micron All Sky Survey (2MASS), to determine stream memberships among local stars and to show the relationship between streaming motions and spiral structure. To achieve these aims, we extend the spiral pattern found from neutral gas towards the Galactic Centre using data from 2MASS. We select a population of 23 075 local disc stars for which complete kinematic data are available. We plot eccentricity against the true anomaly for stellar orbits and identify streams as dense regions of the plot. We reconstruct the spiral pattern by replacing each star at a random position of the inward part of its orbit.

As a result of this study, we find evidence in 2MASS of a bar of length 4.2±0.1 kpc at angle 30°± 10°. We extend spiral structure by more than a full turn towards the Galactic Centre, and confirm that the Milky Way is a two-armed grand-design bisymmetric spiral with pitch angle 5{img}56±0{img}06. Memberships of kinematic groups are assigned to 98 per cent of local disc stars and it is seen that the large majority of local stars have orbits aligned with this spiral structure.


Abstract Copyright: 2012 The Authors Monthly Notices of the Royal Astronomical Society2012 RAS

Journal keyword(s): stars: kinematics and dynamics - Galaxy: kinematics and dynamics - solar neighbourhood - Galaxy: structure

Simbad objects: 14

goto Full paper

goto View the reference in ADS

Number of rows : 14

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2019
#notes
1 * alf Cet LP? 03 02 16.77307 +04 05 23.0596 6.10 4.17 2.53 1.18 0.02 M1.5IIIa 437 0
2 Cl Melotte 22 OpC 03 47 00 +24 07.0           ~ 2908 0
3 Cl Melotte 25 OpC 04 26 54.00 +15 52 00.0           ~ 2581 0
4 * alf CMa SB* 06 45 08.91728 -16 42 58.0171 -1.51 -1.46 -1.46 -1.46 -1.43 A1V+DA 1373 0
5 NAME Crux-Scutum Spiral Arm reg 12 30 -60.0           ~ 263 0
6 NAME Ursa Major Moving Group MGr 12 32 +57.0           ~ 371 2
7 NAME Sgr A* X 17 45 40.03599 -29 00 28.1699           ~ 3267 3
8 NAME Gal Center reg 17 45 40.04 -29 00 28.1           ~ 11007 0
9 * alf Lac PM* 22 31 17.5013090 +50 16 56.968200 3.78 3.78 3.77 3.77 3.80 A1V 238 0
10 NAME Centaurus Arm PoG ~ ~           ~ 70 0
11 NAME Scutum Spiral Arm PoG ~ ~           ~ 256 0
12 NAME Hercules Stream MGr ~ ~           ~ 167 0
13 NAME Hyades Moving Group MGr ~ ~           ~ 225 1
14 NAME Ori Arm PoG ~ ~           ~ 168 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2012MNRAS.422.1283F and select 'bookmark this link' or equivalent in the popup menu


2019.10.21-18:38:42

© Université de Strasbourg/CNRS

    • Contact