English
Related papers

Related papers: Refining the Oort and Galactic constants

200 papers

The rotation curve (RC) of the Milky Way out to $\sim$ 100 kpc has been constructed using $\sim$ 16,000 primary red clump giants (PRCGs) in the outer disk selected from the LSS-GAC and the SDSS-III/APOGEE survey, combined with $\sim$ 5700…

The rotation curve of the Milky Way is commonly used to estimate the local dark matter density $\rho_{{\rm DM},\odot}$. However, the estimates are subject to the choice of the distribution of baryons needed in this type of studies. In this…

Astrophysics of Galaxies · Physics 2019-10-16 P. F. de Salas , K. Malhan , K. Freese , K. Hattori , M. Valluri

Recent measurements of the Milky Way rotation curve found a sharp decline at around $15$-$20$ kpc from the center of the Galaxy, suggesting that the Galactic dark matter halo is much less massive than predicted by other dynamical tracers.…

Astrophysics of Galaxies · Physics 2025-03-11 Xiaowei Ou , Lina Necib , Andrew Wetzel , Anna Frebel , Jeremy Bailin , Micah Oeur

We have studied a sample of more than 25 000 young stars with proper motions and trigonometric parallaxes from the Gaia DR2 catalogue. The relative errors of their parallaxes do not exceed 10\%. The selection of stars belonging to active…

Astrophysics of Galaxies · Physics 2020-08-26 O. I. Krisanova , V. V. Bobylev , A. T. Bajkova

A straightforward determination of the circular-speed curve vc(R) of the Milky Way suggests that near the Sun, vc starts to rise approximately linearly with R. If this result were correct, the Galactic mass density would have to be…

Astrophysics · Physics 2016-06-08 James Binney , Walter Dehnen

In order to test the reliability of determinations of the shapes of galaxies' dark matter halos, we have made such measurements for the Milky Way by two independent methods, which make use of the stellar kinematics in the solar…

Astrophysics · Physics 2017-01-04 R. P. Olling , M. R. Merrifield

We measure the line-of-sight accelerations of 26 binary pulsars due to the Milky Way's gravitational potential, and produce a 3-dimensional map of the acceleration field of the Galaxy. Acceleration measurements directly give us the change…

Astrophysics of Galaxies · Physics 2024-05-22 Thomas Donlon , Sukanya Chakrabarti , Lawrence M. Widrow , Michael T. Lam , Philip Chang , Alice C. Quillen

Using an outer rotation curve of the Galaxy, we explore the galactic constants and the mass of the Galaxy. We show that \Theta_0 of 200 km/s is more favorable than the IAU standard value of 220 km/s, and also show that if \Theta_0 is…

Astrophysics · Physics 2015-06-24 Mareki Honma , Yoshiaki Sofue

By evaluating angular momentum directions of open cluster (OC) samples across various Galactocentric radii, we assessed their orbital plane inclinations. Our findings reveal that, without considering the local tilt of the Galactic disk near…

Astrophysics of Galaxies · Physics 2024-12-31 Liming Peng , Zhihong He

We apply a statistical deconvolution of the parallax errors based on Lucy's inversion method (LIM) to the Gaia-DR3 sources to measure their three dimensional velocity components in the range of Galactocentric distances $R$ between 8 kpc and…

Astrophysics of Galaxies · Physics 2023-01-04 Hai-Feng Wang , Žofia Chrobáková , Martín López-Corredoira , Francesco Sylos Labini

We propose a method to determine the galactic constants R_0 (distance to the Galactic Center) and V_0 (rotation velocity of the Sun) from measurements of distances, radial velocities and proper motions of objects near the solar circle. This…

Astrophysics of Galaxies · Physics 2015-05-28 Y. Sofue , T. Nagayama , M. Matsui , A. Nakagawa

We investigate the rotation curve of the Milky Way using a multi-component mass model including a stellar disk, a gaseous disk, a bulge/bar component, and a dark-matter halo. The stellar and gas contributions are calibrated using recent…

Astrophysics of Galaxies · Physics 2026-03-17 Zi Liu

Orbital properties of stars, computed from their six-dimensional phase space measurements and an assumed Galactic potential, are used to understand the structure and evolution of the Galaxy. Stellar actions, computed from orbits, have the…

The kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia\,EDR3 catalog has been studied. For some of these stars, there are line-of-sight velocities. On the basis of the nonlinear rotation model, the parameters…

Astrophysics of Galaxies · Physics 2023-04-05 V. V. Bobylev , A. T. Bajkova

The aim of the analysis of data from the Gaia Space Observatory is to obtain kinematic parameters of the collective motion of stars in a part of our galaxy. This research is based on a statistical analysis of the motion of {$55,038,539$}…

Astrophysics of Galaxies · Physics 2025-02-18 Petr Zavada , Karel Píška

From multi-epoch WFPC2/HST observations we present astrometric measurements of the absolute motion of the bulge stars. The presence of an extragalactic point-source candidate allows us to measure the difference between the Oort constants,…

Astrophysics · Physics 2007-05-23 L. R. Bedin , G. Piotto , I. R. King , J. Anderson

We measure the circular velocity curve $v_{\rm c}(R)$ of the Milky Way with the highest precision to date across Galactocentric distances of $5\leq R \leq 25$ kpc. Our analysis draws on the $6$-dimensional phase-space coordinates of…

Astrophysics of Galaxies · Physics 2019-03-06 Anna-Christina Eilers , David W. Hogg , Hans-Walter Rix , Melissa Ness

In the fundamental quest of the rotation curve of the Milky Way, the tangent-point (TP) method has long been the simplest way to infer velocities for the inner, low latitude regions of the Galactic disk from observations of the gas…

Astrophysics of Galaxies · Physics 2015-06-03 Laurent Chemin , Florent Renaud , Caroline Soubiran

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 =…

Astrophysics of Galaxies · Physics 2016-01-13 Stacy S. McGaugh