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gaia data release 3 documentation

20.14 Performance verification

20.14.10 chemical_cartography

Orbital parameters, actions, Galactocentric Cartesian coordinates and velocities for the sample of stars used in the DR3 chemical cartographic study of the Milky Way.
For further details see Gaia Collaboration et al. (2023h).

Columns description:

source_id : Source Identifier (long)

A unique single numerical identifier of the source (for a detailed description see gaia_source.source_id).

jr_med : Median radial action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

In axisymmetric potentials, the radial action is an integral of motion that characterises the radial oscillation of a star around its guiding radius. The radial actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the median of the set of radial actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jz_med : Median vertical action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

The vertical action is an integral of motion that characterises the vertical oscillation of a star along its orbit. The vertical actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the median of the set of vertical actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jphi_med : Median azimuthal action per unit mass (positive clockwise) in units of 1967.3865 km s-1 kpc. Equivalent to the median vertical component of the angular momentum. (float)

In axisymmetric potentials, the azimuthal action is a preserved quantity along the orbit of a star around the Galactic Center. It corresponds to the vertical component of the angular momentum and have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the median of the set of azimuthal actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rplane_med : Median in-plane projection of the Galactocentric distance. (float, Length & Distance[kpc])

Given the Cartesian coordinates (X,Y,Z) of a star, the plane-projected distance rplane is computed as (X2+Y2), where X and Y have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc (Gravity Collaboration et al. 2021). This field provides the median of the set of plane-projected distances obtained for different Monte Carlo realisations of the input data.

vrplane_med : Median Galactocentric radial velocity. (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the Galactocentric velocity is computed as the derivative with respect to time of (X2+Y2), where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the median of the set of Galactocentric velocities obtained for different Monte Carlo realisations of the input data.

vz_med : Median vertical velocity. (float, Velocity[km s-1])

This velocity component corresponds to the motion of the star along the direction perpendicular to the Galactic plane. It has been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the median of the set of vertical velocities obtained for different Monte Carlo realisations of the input data.

vphi_med : Median Galactocentric azimuthal velocity (positive clockwise). (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the azimuthal velocity is computed as (YVX-XVY)/(X2+Y2) where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the median of the set of azimuthal velocities obtained for different Monte Carlo realisations of the input data.

zmax_med : Median maximum Galactic height (in absolute value) computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

Median of the maximum value of the vertical distance to the Galactic plane estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the median of the maximum vertical displacements computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rapo_med : Median of the maximum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The apocenter (rapo) is defined as the maximum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the median of the apocenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rperi_med : Median of the minimum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The pericenter (rperi) is defined as the minimum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the median of the pericenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

ecc_med : Median orbital eccentricity computed assuming the Staeckel approximation. (float)

The eccentricity is computed as the ratio (rapo-rperi)/(rapo+rperi), where rapo and rperi refer to the apocenter and pericenter, respectively. It ranges from 0 (circular orbits) to 1 (open orbits). Both the apocenter and the pericenter required to compute the eccentricity have been estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the median of the set of eccentricities computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

x_med : Median of the Cartesian coordinate X. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the median of the set of X coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

y_med : Median of the Cartesian coordinate Y. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the median of the set of Y coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

z_med : Median of the Cartesian coordinate Z. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the median of the set of Z coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

energy_med : Total energy per unit mass assuming median coordinates and velocities. (float, Misc[km2 s-2])

Sum of the kinetic and potential energies (per unit mass) of a star in the Galaxy. The kinetic term is given by the quadratic sum of the velocities (VR, Vϕ, VZ) while the potential term makes use of the rescaled McMillan (2017) potential described in Gaia Collaboration et al. (2023h). This field contains the energy determined by the median values of the velocities and positions computed from several Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jr_hi : Upper confidence limit of the radial action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

In axisymmetric potentials, the radial action is an integral of motion that characterises the radial oscillation of a star around its guiding radius. The radial actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the upper confidence limit (84th percentile) of the set of radial actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jz_hi : Upper confidence limit of the vertical action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

The vertical action is an integral of motion that characterises the vertical oscillation of a star along its orbit. The vertical actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the upper confidence limit (84th percentile) of the set of vertical actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jphi_hi : Upper confidence limit of the azimuthal action per unit mass (positive clockwise) in units of 1967.3865 km s-1 kpc. (float)

In axisymmetric potentials, the azimuthal action is a preserved quantity along the orbit of a star around the Galactic Center. It corresponds to the vertical component of the angular momentum and have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the upper confidence limit (84th percentile) of the set of azimuthal actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rplane_hi : Upper confidence limit of the in-plane projection of the Galactocentric distance. (float, Length & Distance[kpc])

Given the Cartesian coordinates (X,Y,Z) of a star, the plane-projected distance rplane is computed as (X2+Y2), where X and Y have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc (Gravity Collaboration et al. 2021). This field provides the upper confidence limit (84th percentile) of the set of plane-projected distances obtained for different Monte Carlo realisations of the input data.

vrplane_hi : Upper confidence limit of the Galactocentric radial velocity. (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the Galactocentric velocity is computed as the derivative with respect to time of (X2+Y2), where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the upper confidence limit (84th percentile) of the set of Galactocentric velocities obtained for different Monte Carlo realisations of the input data.

vz_hi : Upper confidence limit of the vertical velocity. (float, Velocity[km s-1])

This velocity component corresponds to the motion of the star along the direction perpendicular to the Galactic plane. It has been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the upper confidence limit (84th percentile) of the set of vertical velocities obtained for different Monte Carlo realisations of the input data.

vphi_hi : Upper confidence limit of the Galactocentric azimuthal velocity (positive clockwise). Equivalent to the upper confidence limit of the vertical component of the angular momentum. (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the azimuthal velocity is computed as (YVX-XVY)/(X2+Y2) where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the upper confidence limit (84th percentile) of the set of azimuthal velocities obtained for different Monte Carlo realisations of the input data.

zmax_hi : Upper confidence limit of the maximum Galactic height (in absolute value) computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

Upper confidence limit (84th percentile) of the maximum value of the vertical distance to the Galactic plane estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the upper confidence limit (84th percentile) of the maximum vertical displacements computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rapo_hi : Upper confidence limit of the of the maximum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The apocenter (rapo) is defined as the maximum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the upper confidence limit (84th percentile) of the apocenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rperi_hi : Upper confidence limit of the of the minimum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The pericenter (rperi) is defined as the minimum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the upper confidence limit (84th percentile) of the pericenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

ecc_hi : Upper confidence limit of the orbital eccentricity computed assuming the Staeckel approximation. (float)

The eccentricity is computed as the ratio (rapo-rperi)/(rapo+rperi), where rapo and rperi refer to the apocenter and pericenter, respectively. It ranges from 0 (circular orbits) to 1 (open orbits). Both the apocenter and the pericenter required to compute the eccentricity have been estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the upper confidence limit (84th percentile) of the set of eccentricities computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

x_hi : Upper confidence limit of the Cartesian coordinate X. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the upper confidence limit (84th percentile) of the set of X coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

y_hi : Upper confidence limit of the Cartesian coordinate Y. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the upper confidence limit (84th percentile) of the set of Y coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

z_hi : Upper confidence limit of the Cartesian coordinate Z. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the upper confidence limit (84th percentile) of the set of Z coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jr_lo : Lower confidence limit of the radial action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

In axisymmetric potentials, the radial action is an integral of motion that characterises the radial oscillation of a star around its guiding radius. The radial actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the lower confidence limit (16th percentile) of the set of radial actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jz_lo : Lower confidence limit of the vertical action per unit mass in units of 1967.3865 km s-1 kpc computed assuming the Staeckel approximation. (float)

The vertical action is an integral of motion that characterises the vertical oscillation of a star along its orbit. The vertical actions have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the lower confidence limit (16th percentile) of the set of vertical actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

jphi_lo : Lower confidence limit of the azimuthal action per unit mass (positive clockwise) in units of 1967.3865 km s-1 kpc. Equivalent to the lower confidence limit of the vertical component of the angular momentum. (float)

In axisymmetric potentials, the azimuthal action is a preserved quantity along the orbit of a star around the Galactic Center. It corresponds to the vertical component of the angular momentum and have been computed numerically by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). The product of these parameters is used as normalisation constant for this field (RV=1967.3865 km s-1 kpc). This field contains the lower confidence limit (16th percentile) of the set of azimuthal actions computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rplane_lo : Lower confidence limit of the in-plane projection of the Galactocentric distance. (float, Length & Distance[kpc])

Given the Cartesian coordinates (X,Y,Z) of a star, the plane-projected distance rplane is computed as (X2+Y2), where X and Y have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc (Gravity Collaboration et al. 2021). This field provides the lower confidence limit (16th percentile) of the set of plane-projected distances obtained for different Monte Carlo realisations of the input data.

vrplane_lo : Lower confidence limit of the Galactocentric radial velocity. (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the Galactocentric velocity is computed as the derivative with respect to time of (X2+Y2), where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the lower confidence limit (16th percentile) of the set of Galactocentric velocities obtained for different Monte Carlo realisations of the input data.

vz_lo : Lower confidence limit of the vertical velocity. (float, Velocity[km s-1])

This velocity component corresponds to the motion of the star along the direction perpendicular to the Galactic plane. It has been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the lower confidence limit (16th percentile) of the set of vertical velocities obtained for different Monte Carlo realisations of the input data.

vphi_lo : Lower confidence limit of the Galactocentric azimuthal velocity (positive clockwise). (float, Velocity[km s-1])

Given the Cartesian coordinates (X,Y,Z) of a star, the azimuthal velocity is computed as (YVX-XVY)/(X2+Y2) where X, Y and their respective velocities have been computed assuming a Galactocentric distance of the Sun R=8.249 kpc and a circular velocity at R of V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field provides the lower confidence limit (16th percentile) of the set of azimuthal velocities obtained for different Monte Carlo realisations of the input data.

zmax_lo : Lower confidence limit of the maximum Galactic height (in absolute value) computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

Lower confidence limit (16th percentile) of the maximum value of the vertical distance to the Galactic plane estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the lower confidence limit (16th percentile) of the maximum vertical displacements computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rapo_lo : Lower confidence limit of the of the maximum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The apocenter (rapo) is defined as the maximum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the lower confidence limit (16th percentile) of the apocenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

rperi_lo : Lower confidence limit of the of the minimum Galactocentric distance computed assuming the Staeckel approximation. (float, Length & Distance[kpc])

The pericenter (rperi) is defined as the minimum Galactocentric distance of a star along its orbit. It is estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the lower confidence limit (16th percentile) of the pericenters computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

ecc_lo : Lower confidence limit of the orbital eccentricity computed assuming the Staeckel approximation. (float)

The eccentricity is computed as the ratio (rapo-rperi)/(rapo+rperi), where rapo and rperi refer to the apocenter and pericenter, respectively. It ranges from 0 (circular orbits) to 1 (open orbits). Both the apocenter and the pericenter required to compute the eccentricity have been estimated by Galpy (Bovy 2015) for a rescaled version of the potential of McMillan (2017). The Galactocentric distance of the Sun is set at R=8.249 kpc and the circular velocity at R is V=238.5 km s-1 (Gravity Collaboration et al. 2021; Schönrich et al. 2010). This field contains the lower confidence limit (16th percentile) of the set of eccentricities computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

x_lo : Lower confidence limit of the Cartesian coordinate X. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the lower confidence limit (16th percentile) of the set of X coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

y_lo : Lower confidence limit of the Cartesian coordinate Y. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the lower confidence limit (16th percentile) of the set of Y coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.

z_lo : Lower confidence limit of the Cartesian coordinate Z. (float, Length & Distance[kpc])

The adopted convention for the Cartesian coordinate system locates the Galactic Center at the origin and the Sun at (X,Y,Z)=(R,0,Z), where R=8.249 kpc (Gravity Collaboration et al. 2021) and Z=0.0208 kpc (Bennett and Bovy 2019). This field contains the lower confidence limit (16th percentile) of the set of Z coordinates computed for different Monte Carlo realisations of the proper motions, distances and line-of-sight velocities.