Rediscovering the Galactic outer disk with LAMOST data

Content Provider	Scilit
Author	Liu, Chao Xu, Yan Wang, Haifeng Wan, Junchen
Copyright Year	2017
Description	From the derived stellar density profile using LAMOST giant stars, we find that the Galactic disk does not show truncation or break, but smoothly transit to the halo from 19 kpc. The scale length of the outer disk is only 1.6 ± 0.1 kpc, substantially smaller than previous results. This implies that the shapes of the inner and outer disk are different. Meanwhile, the disk flaring is not only found in older populations, but also in younger population. Moreover, the vertical oscillations of the disk are identified in a wide range or R from 8 to 14 kpc. We also find that the velocity dispersion profile as a function of the Galactocentric radius is flat with scale length of 26.3 ± 3.2 kpc. We confirm that the radial velocity profile in outer disk is significantly affected by asymmetric motion. The bar with either a slower or a faster pattern speed can induce the similar radial asymmetric motion.
Related Links	http://arxiv.org/pdf/1712.03977 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/573B7682587166F10308DCAA41D708CF/S1743921317010870a.pdf/div-class-title-rediscovering-the-galactic-outer-disk-with-lamost-data-div.pdf
Ending Page	115
Page Count	7
Starting Page	109
ISSN	17439213
e-ISSN	17439221
DOI	10.1017/s1743921317010870
Journal	Proceedings of the International Astronomical Union
Issue Number	S334
Volume Number	13
Language	English
Publisher	Cambridge University Press (CUP)
Publisher Date	2017-07-01
Access Restriction	Open
Subject Keyword	Proceedings of the International Astronomical Union Astronomy and Astrophysics General Structure Disk Kinematics and Dynamics
Content Type	Text
Resource Type	Article
Subject	Astronomy and Astrophysics Space and Planetary Science