Related papers: Rediscovering the Galactic outer disk with LAMOST …
Average stellar orbits of the Galactic disk may have some small intrinsic ellipticity which breaks the exact axisymmetry and there may also be some migration of stars inwards or outwards. Both phenomena can be detected through kinematic…
Aims. We explore the outer Galactic disc up to a Galactocentric distance of 30 kpc to derive its parameters and measure the magnitude of its flare. Methods. We obtained the 3D density of stars of type F8V-G5V with a colour selection from…
We find that Galactic disk stars near the anticenter exhibit velocity asymmetries in both the Galactocentric radial and vertical components across the mid-plane as well as azimuthally. These findings are based on LAMOST spectroscopic…
We confirm, quantify, and provide a table of the coherent velocity substructure of the Milky Way disk within 2 kpc of the Sun towards the Galactic anticenter, with 0.2 kpc resolution. We use the radial velocities of ~340,000 F-type stars…
A detailed measurement is made of the metallicity distributions, kinematics and dynamics of the thin and thick disks, across a large disk volume (5.0 $\leq$ $R$ $\leq$ 15.0 kpc and $|Z|$ $\leq$3.0 kpc), by using the LAMOST-APOGEE red clump…
This paper describes test particle simulations of the response of the outer parts of Galactic disks to barring and spiral structure. Simulations are conducted for cold Mestel disks and warm quasi-exponential disks with completely flat…
As part of a stellar population sampling program, a series of photometric probes at various field sizes and depths have been obtained in a low extinction window in the galactic anticentre direction. Such data set strong constraints on the…
High resolution spectra data of red clump stars towards the NGP have been obtained with the high resolution spectrograph Elodie at OHP for Tycho-2 selected stars. Combined with Hipparcos local analogues, we determine both the gravitational…
This study is an investigation of the stellar density profile of the Galactic disc in the Anticentre direction. We select over 40,000 early A stars from IPHAS photometry in the Galactic longitude range 160 < l < 200 close to the equatorial…
We perform analysis of the three-dimensional kinematics of Milky Way disk stars in mono-age populations. We focus on stars between Galactocentric distances of $R=6$ and 14 \,kpc, selected from the combined LAMOST DR4 red clump giant stars…
The observed flaring of HI disk in the outer region of galaxies has been used in the past to determine the shape of the dark matter halo. Previous studies based on this concept suggest a slightly oblate halo (axis ratio ~ 0.8) for our…
We have performed a high mass and force resolution simulation of an idealized galaxy forming from dissipational collapse of gas embedded in a spherical dark matter halo. The simulation includes star formation and effects of stellar…
The mass distribution of the Galactic disk is constructed from the terminal velocity curve and the mass discrepancy-acceleration relation. Mass models numerically quantifying the detailed surface density profiles are tabulated. For $R_0 =…
We investigate the evolution of galactic disks in N-body Tree-SPH simulations. We find that disks, initially truncated at three scale-lengths, can triple their radial extent, solely driven by secular evolution. Both Type I (single…
We present the peculiar in-plane velocities derived from the LAMOST red clump stars. From the variations of the in-plane velocity with the Galactocentric radius for the young and old red clump stars, we are able to identify two types of…
We present a comprehensive study of the kinematic properties of the different Galactic disk populations, as defined by the chemical abundance ratios and stellar ages, across a large disk volume (4.5 $\leq$ R $\leq$ 15.0 kpc and $|Z|$ $\leq$…
Using a sample of nearly 140,000 red clump stars selected from the LAMOST and Gaia Galactic surveys, we have mapped mean vertical velocity $\overline{V_{z}}$ in the $X$-$Y$ plane for a large volume of the Galactic disk (6 $< R < 16$ kpc;…
We consider a thickness of stellar disks of late-type galaxies by analyzing the R and K_s band photometric profiles for two independent samples of edge-on galaxies. The main goal is to verify a hypotesis that a thickness of old stellar…
We present the serendipitous discovery of an extremely broad ($\Delta V_{LSR} \sim 150$ km/s), faint ($T_{mb} < 10 \textrm{mK}$), and ubiquitous 1667 and 1665 MHz ground-state thermal OH emission towards the 2nd quadrant of the outer Galaxy…
The outer stellar halos of galaxies contain vital information about the formation history of galaxies, since the relaxation timescales in the outskirts are long enough to keep the memory, while the information about individual formation…