On the Structure of the Sagittarius Spiral Arm in the Inner Milky Way

Journal
Date Issued
2024
Author(s)
Bian, S. B.
•
Wu, Y. W.
•
Xu, Y.
•
Reid, M. J.
•
Li, J. J.
•
Zhang, B.
•
Menten, K. M.
•
•
Brunthaler, A.
DOI
Abstract
We report measurements of trigonometric parallax and proper motion for two 6.7 GHz methanol and two 22 GHz water masers located in the far portion of the Sagittarius spiral arm as part of the BeSSeL Survey. Distances for these sources are estimated from parallax measurements combined with three-dimensional kinematic distances. The distances of G033.64−00.22, G035.57−00.03, G041.15−00.20, and G043.89−00.78 are 9.9 ± 0.5, 10.2 ± 0.6, 7.6 ± 0.5, and 7.5 ± 0.3 kpc, respectively. Based on these measurements, we suggest that the Sagittarius arm segment beyond about 8 kpc from the Sun in the first Galactic quadrant should be adjusted radially outward relative to previous models. This supports the suggestion of Xu et al. that the Sagittarius and Perseus spiral arms might merge in the first quadrant before spiraling inward to the far end of the Galactic bar.
Volume
167
Issue
6
Start page
267
Uri
Url
Issn Identifier
0004-6256
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Bian_2024_AJ_167_267.pdf

Description
PDF editoriale
Size

2.09 MB

Format

Adobe PDF

Checksum (MD5)

10ef3894070b1af9a1c565dea813d7ff