English
Related papers

Related papers: Weighing the Galactic disk using phase-space spira…

200 papers

We have applied our method for weighing the Galactic disk using phase-space spirals to the Gaia EDR3 proper motion sample. For stars in distant regions of the Galactic disk, the latitudinal proper motion has a close projection with vertical…

Astrophysics of Galaxies · Physics 2022-07-06 Axel Widmark , Chervin F. P. Laporte , Giacomo Monari

We present a new method for inferring the gravitational potential of the Galactic disk, using the time-varying structure of a phase-space spiral in the $(z,w)$-plane (where $z$ and $w$ represent vertical position and vertical velocity). Our…

Astrophysics of Galaxies · Physics 2021-11-30 Axel Widmark , Chervin F. P. Laporte , Pablo F. de Salas

We infer the gravitational potential of the Galactic disk by analysing the phase-space densities of 120 stellar samples in 40 spatially separate sub-regions of the solar neighbourhood, using Gaia's second data release (DR2), in order to…

Astrophysics of Galaxies · Physics 2021-02-10 Axel Widmark , Pablo Fernández de Salas , Giacomo Monari

In this fourth article on weighing the Galactic disk using the shape of the phase-space spiral, we have tested our method on a billion particle three-dimensional N-body simulation, comprised of a Milky Way like host galaxy and a merging…

Astrophysics of Galaxies · Physics 2022-07-06 Axel Widmark , Jason A. S. Hunt , Chervin F. P. Laporte , Giacomo Monari

We use stellar kinematics from the latest Gaia data release (DR2) to measure the local dark matter density $\rho_{\rm DM}$ in a heliocentric cylinder of radius $R= 150 \ {\rm pc}$ and half-height $z= 200 \ {\rm pc}$. We also explore the…

Astrophysics of Galaxies · Physics 2019-04-18 Jatan Buch , John Shing Chau Leung , JiJi Fan

We probe the gravitational force perpendicular to the Galactic plane at the position of the Sun based on a sample of red giants, with measurements taken from the DR3 Gaia catalogue. Measurements far out of the Galactic plane up to 3.5 kpc…

Astrophysics of Galaxies · Physics 2024-07-02 O. Bienaymé , A. C. Robin , J. -B. Salomon , C. Reylé

We use Gaia photometry and astrometry to estimate the vertical spatial structure of the Milky Way at the Solar radius, formally accounting for sample incompleteness (the selection function) and parallax measurement uncertainty. Our results…

Astrophysics of Galaxies · Physics 2022-02-16 Andrew Everall , Vasily Belokurov , N. Wyn Evans , Douglas Boubert , Robert J. J. Grand

We present a novel method for determining the total matter surface density of the Galactic disk by analysing the kinematics of a dynamically cold stellar stream that passes through or close to the Galactic plane. The method relies on the…

Astrophysics of Galaxies · Physics 2020-06-24 Axel Widmark , Khyati Malhan , Pablo F. de Salas , Sofia Sivertsson

Estimates of the dynamical surface mass density at the solar Galactocentric distance are commonly derived assuming that the disk is in vertical equilibrium with the Galactic potential. This assumption has recently been called into question,…

Astrophysics of Galaxies · Physics 2015-05-27 F. J. Sanchez-Salcedo , Chris Flynn , A. M. Hidalgo-Gamez

We used red clump stars to measure the surface mass density of the Galactic disk in the solar neighbourhood. High resolution spectra of red clump stars towards the NGP have been obtained with the ELODIE spectrograph at OHP for Tycho-2…

Astrophysics · Physics 2009-11-11 O. Bienaymé , C. Soubiran , T. V. Mishenina , V. V. Kovtyukh , A. Siebert

We present results from a detailed dynamical analysis of five high surface brightness, late type spirals, studied with the aim to quantify the luminous-to-dark matter ratio inside their optical radii. The galaxies' stellar light…

Astrophysics · Physics 2009-11-07 Thilo Kranz , Adrianne Slyz , Hans-Walter Rix

We determine the total dynamical matter density in the solar neighbourhood using the second Gaia data release (DR2). The dynamical matter density distribution is inferred in a framework of a Bayesian hierarchical model, which accounts for…

Astrophysics of Galaxies · Physics 2019-02-27 Axel Widmark

From a sample of 15651 RR Lyrae with accurate proper motions in Gaia DR2, we measure the azimuthally averaged kinematics of the inner stellar halo between 1.5 kpc and 20 kpc from the Galactic centre. We find that their kinematics are…

Astrophysics of Galaxies · Physics 2019-03-06 Christopher Wegg , Ortwin Gerhard , Marie Bieth

Dynamical estimates of the mass surface density at the solar radius can be made up to a height of 4 kpc using thick disk stars as tracers of the potential. We investigate why different Jeans estimators of the local surface density lead to…

Astrophysics of Galaxies · Physics 2016-01-27 F. J. Sanchez-Salcedo , C. Flynn , J. A. de Diego

I present a new method of deriving the shape of the dark matter (DM) halos of spiral galaxies. The method relies on the comparison of model predictions with high spectral and spatial resolution HI observations of the gas layer. The…

Astrophysics · Physics 2009-10-28 Rob P. Olling

Recent studies have shown that the passage of a massive satellite through the disk of a spiral galaxy can induce vertical wobbles in the disk and produce features such as in-plane rings and phase-space spirals. Here we analyze a…

Astrophysics of Galaxies · Physics 2019-07-10 Tim Haines , Elena D'Onghia , Benoit Famaey , Chervin Laporte , Lars Hernquist

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…

Astrophysics · Physics 2009-11-07 A. Siebert , O. Bienayme , C. Soubiran

We explore the relative importance of the stellar mass density as compared to the inner dark halo, using the observed gas kinematics throughout the disk of the spiral galaxy NGC 4254 (Messier 99). We perform hydrodynamical simulations of…

Astrophysics · Physics 2009-11-06 Thilo Kranz , Adrianne Slyz , Hans-Walter Rix

We extend the concept of galaxy environment from the local galaxy number density to the gravitational potential and its functions like the shear tensor. For this purpose we examine whether or not one can make an accurate estimation of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Hyunbae Park , Juhan Kim , Changbom Park

We study the vertical stellar distribution of the Milky Way thin disk in detail with particular focus on the outer disk. We treat the galactic disk as a gravitationally coupled, three-component system consisting of stars, atomic hydrogen…

Astrophysics of Galaxies · Physics 2018-10-03 Suchira Sarkar , Chanda J Jog
‹ Prev 1 2 3 10 Next ›