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Related papers: The local density of matter mapped by Hipparcos

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We determine the surface density of matter in the disc of the Galaxy at the solar position using K giant stars. The local space density and luminosity function of the giants is determined using parallaxes from the Hipparcos satellite; for…

Astrophysics · Physics 2009-11-10 Johan Holmberg , Chris Flynn

Hipparcos data provide the first, volume limited and absolute magnitude limited homogeneous tracer of stellar density and velocity distributions in the solar neighbourhood. The density of A-type stars more luminous than $M_v=2.5$ can be…

Astrophysics · Physics 2007-05-23 M. Crézé , E. Chereul , O. Bienaymé , C. Pichon

We have re-estimated the surface density of the Galactic disk in the solar neighborhood within $\pm$ 0.4 kpc of the Sun using parallaxes and proper motions of a kinematically and spatially unbiased sample of 1476 old bright red giant stars…

Astrophysics · Physics 2009-11-10 V. I. Korchagin , T. M. Girard , T. V. Borkova , D. I. Dinescu , W. F. van Altena

We determine the total dynamical density in the solar neighbourhood using the Tycho-Gaia Astrometric Solution (TGAS) catalogue. Astrometric measurements of proper motion and parallax of stars inform us of both the stellar number density…

Astrophysics of Galaxies · Physics 2019-11-04 Axel Widmark , Giacomo Monari

We determine the Galactic potential in the solar neigbourhood from RAVE observations. We select red clump stars for which accurate distances, radial velocities, and metallicities have been measured. Combined with data from the 2MASS and…

We measured the surface mass density of the Galactic disk at the solar position, up to 4 kpc from the plane,by means of the kinematics of ~400 thick disk stars. The results match the expectations for the visible mass only, and no dark…

Astrophysics of Galaxies · Physics 2012-04-19 C. Moni Bidin , G. Carraro , R. A. Mendez , R. Smith

The surface density and vertical distribution of stars, stellar remnants, and gas in the solar vicinity form important ingredients for understanding the star formation history of the Galaxy as well as for inferring the local density of dark…

Astrophysics of Galaxies · Physics 2015-11-18 Christopher F. McKee , Antonio Parravano , David J. Hollenbach

We estimated the dynamical surface mass density (Sigma) at the solar Galactocentric distance between 2 and 4 kpc from the Galactic plane, as inferred from the observed kinematics of the thick disk. We find Sigma(z=2 kpc)=57.6+-5.8 Mo pc^-2,…

Astrophysics of Galaxies · Physics 2015-05-20 C. Moni Bidin , G. Carraro , R. A. Mendez , W. F. van Altena

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

New and more reliable distances and proper motions of a large number of stars in the Tycho-Gaia Astrometric Solution (TGAS) catalogue allow to calculate the local matter density distribution more precisely than earlier. We devised a method…

Astrophysics of Galaxies · Physics 2017-11-15 Rain Kipper , Elmo Tempel , Peeter Tenjes

We estimated the dynamical surface mass density Sigma at the solar position between Z=1.5 and 4 kpc from the Galactic plane, as inferred from the kinematics of thick disk stars. The formulation is exact within the limit of validity of a few…

Astrophysics of Galaxies · Physics 2015-06-04 C. Moni Bidin , G. Carraro , R. A. Mendez , R. Smith

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

The velocity distribution of neighbouring stars is deduced from the Hipparcos proper motions. We have used a classical Schwarzschild decomposition and also developed a dynamical model for quasi-exponential stellar discs. This model is a 3-D…

Astrophysics · Physics 2007-05-23 O. Bienaymé

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

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

An analysis of the kinematics of 412 stars at 1-4 kpc from the Galactic mid-plane by Moni Bidin et al. (2012) has claimed to derive a local density of dark matter that is an order of magnitude below standard expectations. We show that this…

Astrophysics of Galaxies · Physics 2013-04-24 Jo Bovy , Scott Tremaine

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 present the recent robust determination of the value of the Dark Matter density at the Sun's location ($\rho_\odot$) with a technique that does not rely on a global mass-modeling of the Galaxy. The method is based on the local equation…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-18 Fabrizio Nesti , Paolo Salucci

The rotation curve, the total mass and the gravitational potential of the Galaxy are sensitive measurements of the dark matter halo profile. In this publication cuspy and cored DM halo profiles are analysed with respect to recent…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-30 Markus Weber , Wim de Boer

We present a method to derive the dynamical mass of face-on galaxy disks using their neutral hydrogen (HI) velocity dispersion. We have applied the method to nearby, gas rich galaxies that have extended HI gas disks and have low…

Astrophysics of Galaxies · Physics 2020-02-05 Mousumi Das , Stacy McGaugh , Roger Ianjamasimanana , James Schombert , K. S. Dwarakanath
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