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Related papers: Kinematic Distances: A Monte Carlo Method

200 papers

We present a new geometrical method for measuring the distance to the Galactic center (R_0) by solving for the Keplerian orbit of individual stars bound to the black hole associated with the Sgr A* from radial velocity and proper motion…

Astrophysics · Physics 2009-10-31 Samir Salim , Andrew Gould

We increase the number of remote halo tracers by using blue horizontal branch (BHB) stars out to Galactocentric distances of 130 kpc. We use SDSS EDR photometry and the VLT to detect 16 BHB stars at Galactocentric distances 70 < r < 130,…

Astrophysics · Physics 2007-05-23 L. Clewley , S. J. Warren , P. C. Hewett , M. Wilkinson , W. N. Evans

This study presents the methodology for creating a cost-efficient radio astronomy telescope that can be used to detect 21 cm emissions (1420.405 MHz) and determine the distribution and kinematics of neutral hydrogen specifically in the…

Instrumentation and Methods for Astrophysics · Physics 2024-11-04 Jack Phelps

We present a simple set of kinematic criteria that can distinguish between galaxies dominated by ordered rotational motion and those involved in major merger events. Our criteria are based on the dynamics of the warm ionized gas (as traced…

We present a geometrodynamical method for determining distances to orbital streams of HI gas in the Galaxy. The method makes use of our offset from the Galactic centre and assumes that the gas comprising the stream nearly follows a planar…

Astrophysics · Physics 2009-11-13 Shoko Jin , Donald Lynden-Bell

Using the HI Emission/Absorption method, we resolve the kinematic distance ambiguity and derive distances for 149 of 182 (82%) HII regions discovered by the Green Bank Telescope HII Region Discovery Survey (GBT HRDS). The HRDS is an X-band…

Astrophysics of Galaxies · Physics 2015-06-05 L. D. Anderson , T. M. Bania , Dana S. Balser , Robert T. Rood

Stars slingshotted by the supermassive black hole at the Galactic centre will escape the Milky Way so quickly that their trajectories will be almost straight lines. Previous works have shown how these `hypervelocity stars' are subsequently…

Astrophysics of Galaxies · Physics 2020-04-03 Douglas Boubert , Denis Erkal , Alessia Gualandris

We measure the Galactic rotation curve and its first two vertical derivatives in the first and fourth quadrants of the Milky Way using the 21 cm VGPS and SGPS. We find tangent velocities of the atomic gas as a function of galactic longitude…

Astrophysics · Physics 2009-06-23 E. S. Levine , Carl Heiles , Leo Blitz

We apply the statistical methods by Schoenrich, Binney & Asplund to assess the quality of distances and kinematics in the RAVE-TGAS and LAMOST-TGAS samples of Solar neighbourhood stars. These methods yield a nominal distance accuracy of…

Astrophysics of Galaxies · Physics 2017-10-11 Ralph Schönrich , Michael Aumer

Traditional Markov Chain Monte Carlo methods suffer from low acceptance rate, slow mixing and low efficiency in high dimensions. Hamiltonian Monte Carlo resolves this issue by avoiding the random walk. Hamiltonian Monte Carlo (HMC) is a…

Astrophysics · Physics 2008-11-26 Amir Hajian

Large samples of Field Horizontal Branch (FHB) stars make excellent tracers of the Galactic halo; by studying their kinematics, one can infer important physical properties of our Galaxy. Here we present the results of a medium-resolution…

The Milky Way's neutral hydrogen (HI) disk is warped and flared. However, a dearth of accurate HI-based distances has thus far prevented the development of an accurate Galactic disk model. Moreover, the extent to which our Galaxy's stellar…

Astrophysics of Galaxies · Physics 2019-02-05 Xiaodian Chen , Shu Wang , Licai Deng , Richard de Grijs , Chao Liu , Hao Tian

We determine the distance to 38 clusters of galaxies in the redshift range 0.14 < z < 0.89 using X-ray data from Chandra and Sunyaev-Zeldovich Effect data from the Owens Valley Radio Observatory and the Berkeley-Illinois-Maryland…

Astrophysics · Physics 2009-11-11 M. Bonamente , M. Joy , S. La Roque , J. Carlstrom , E. Reese , K. Dawson

The position of the Sun inside the Milky Way's disc hampers the study of the spiral arm structure. We aim to analyse the spiral arms along the line-of-sight towards the Galactic centre (GC) to determine their distance, extinction, and…

Astrophysics of Galaxies · Physics 2021-09-08 Francisco Nogueras-Lara , Rainer Schödel , Nadine Neumayer

The kinematics of galaxies with 10 megaparsecs (10 Mpc) of the Milky Way is investigated using published distances and radial velocities. With respect to the average Hubble flow (isotropic or simple anisotropic), there is NO systematic…

Astrophysics · Physics 2009-11-07 Alan B. Whiting

We determine the influence of the Milky Way's warp on the kinematics of stars across the disc, and therefore measure its precession rate and line of nodes under different assumptions. We do this by applying Jeans' first equation to a model…

Astrophysics of Galaxies · Physics 2024-07-31 Viktor Hrannar Jónsson , Paul J. McMillan

We present a new technique to determine distances to major star-forming regions across the Perseus Molecular Cloud, using a combination of stellar photometry, astrometric data, and $\rm ^{12} CO$ spectral-line maps. Incorporating the Gaia…

We revisit the moving groups (MGs) in the solar neighborhood with a sample of 91969 nearby stars constructed from LAMOST DR7. Using the wavelet technique and Monte Carlo simulations, five MGs together with a new candidate located at $V…

Astrophysics of Galaxies · Physics 2021-11-29 Yong Yang , Jingkun Zhao , Jiajun Zhang , Xianhao Ye , Gang Zhao

Using near infrared UKIDSS Galactic Plane Survey data, we make extinction measurements to individual stars along the same line of sight as molecular clouds. Using an existing 3D extinction map of the inner Galaxy, that provides line of…

Astrophysics of Galaxies · Physics 2015-05-18 J. J. Stead , M. G. Hoare

Pixel-space full spectrum fitting exploiting non-linear $\chi^2$ minimization became a \emph{de facto} standard way of deriving internal kinematics from absorption line spectra of galaxies and star clusters. However, reliable estimation of…

Instrumentation and Methods for Astrophysics · Physics 2020-04-29 Igor V. Chilingarian , Kirill A. Grishin
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