Gaia Data Release 3: Chemical cartography of the Milky Way
- Recio-Blanco, A. et al
- arXiv:2206.05534
 | Milky Way stars in the \gspspec\ database (General sample). This HEALPix map in Galactic coordinates has a resolution of 0.46$^\circ$. The colour code corresponds to the median of the stellar distance from the Sun. This colour code enhances thin and thick disc populations in the Galactic plane, far from the solar neighbourhood. The Galactic bulge stars are also visible in the central region. Finally, the higher distance of the Magellanic Clouds and of several globular clusters reveal their presence in the regions far from the Galactic plane otherwise dominated by foreground stars of the solar neighbourhood. |
 | Same as Fig.\ref{Fig.lb} but colour coded with the median of the stellar metallicity \meta\ in each pixel. In the Galactic plane, the higher metallicity values of the thin disc are visible. In the central Galactic regions, a more metal-poor mix of bulge and thick disc populations is present. Far from the disc plane, high-metallicity thin disc stars at low distances from the Sun and more distant metal-poor halo stars are present. |
 | Same as Fig.\ref{Fig.lbBIS} but colour-coded with the median of \alphaFe\ in each pixel. The large structures close to the ecliptic poles are artifacts caused by the \Gaia\ scanning law (see text). Thin disc stars are visible in the plane thanks to their low \alphaFe\ values. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Same as Fig.~\ref{Fig.lbBIS} but for different distance intervals shown from the closest (top panel of left column) to the most distant (bottom panel of right column). The distance ranges adopted in each panel are indicated in their lower right corner together with the number of stars in their bottom left corner. The colour code corresponds to the median of the metallicity and is continuous between the first four subpanels showing rather metal-rich stars, and the two last panels dominated by metal-poor populations. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Galactic maps for the General sample stars colour coded according to stellar count, the median of \meta,\ and the median of \alphaFe\ (from left to right, respectively). The top row shows the maps in Cartesian coordinates (X,Y), with the background image being the Milky Way sketch from \cite{Churchwell2009}. In the bottom row, $R$ and $Z$ are the distances from the Galactic centre and plane, respectively. |
 | Kiel diagrams across the Milky Way for the Medium Quality sample, colour coded according to the median of the mean metallicity. The number of stars in each subpanel is indicated in its upper left corner. The global ($R$, $Z$) distribution of Fig.~\ref{Fig.XY} (bottom row) is shown in the background with grey levels. Moving away from the Sun, the sample becomes dominated by intrinsically bright giants. |
 | Same as Fig.~\ref{Fig.MW_Kiel} but for \alphaFe\ versus \meta\ (star counts). |
 | Kiel diagram of all the Medium Quality stars located within 1~kpc of the Galactic plane. The location of the HotTO, RGB, and Massive subsamples is illustrated. Their spatial distribution and chemical properties are detailed in Figs.~\ref{Fig.SelFuncXY1}, \ref{Fig.SelFuncXY2}, and \ref{Fig.SelFuncXY3}, respectively. |
 | HotTO stars of the Medium Quality sample located within 1~kpc of the Galactic plane. Their XY spatial distribution is shown within $\pm$4~kpc of the Sun, colour coded according to stellar count and the median of the mean metallicity (left and central panels, respectively). The solar position is indicated by a filled star coloured according to solar metallicity (\meta=0.0~dex). The right panel shows the evolution of calcium (top) and sulfur (bottom) abundances with respect to iron abundances versus the mean metallicity. |
 | HotTO stars of the Medium Quality sample located within 1~kpc of the Galactic plane. Their XY spatial distribution is shown within $\pm$4~kpc of the Sun, colour coded according to stellar count and the median of the mean metallicity (left and central panels, respectively). The solar position is indicated by a filled star coloured according to solar metallicity (\meta=0.0~dex). The right panel shows the evolution of calcium (top) and sulfur (bottom) abundances with respect to iron abundances versus the mean metallicity. |
 | HotTO stars of the Medium Quality sample located within 1~kpc of the Galactic plane. Their XY spatial distribution is shown within $\pm$4~kpc of the Sun, colour coded according to stellar count and the median of the mean metallicity (left and central panels, respectively). The solar position is indicated by a filled star coloured according to solar metallicity (\meta=0.0~dex). The right panel shows the evolution of calcium (top) and sulfur (bottom) abundances with respect to iron abundances versus the mean metallicity. |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for RGB stars within 1~kpc of the Galactic plane |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for RGB stars within 1~kpc of the Galactic plane |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for RGB stars within 1~kpc of the Galactic plane |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for Massive stars located within 400~pc of the Galactic plane, thus focusing attention on the thin disc. The spiral arm structure is visible in the left and central panels. Calcium and nitrogen abundance distributions are shown in the right top and bottom panels, respectively. For comparison, the distribution of the RGB stars in terms of calcium abundance is shown in grey in the top panel |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for Massive stars located within 400~pc of the Galactic plane, thus focusing attention on the thin disc. The spiral arm structure is visible in the left and central panels. Calcium and nitrogen abundance distributions are shown in the right top and bottom panels, respectively. For comparison, the distribution of the RGB stars in terms of calcium abundance is shown in grey in the top panel |
 | Same as Fig.~\ref{Fig.SelFuncXY1} but for Massive stars located within 400~pc of the Galactic plane, thus focusing attention on the thin disc. The spiral arm structure is visible in the left and central panels. Calcium and nitrogen abundance distributions are shown in the right top and bottom panels, respectively. For comparison, the distribution of the RGB stars in terms of calcium abundance is shown in grey in the top panel |
 | Cerium abundances for the coolest Massive and RGB stars of the Medium Quality sample located close to the Galactic plane and colour coded according to stellar density and the median of \CaFe\ (top and bottom panel, respectively). |
 | Radial gradients for metallicity (top) and \alphaFe\ (bottom) for different distances from the Galactic midplane (in kpc; see the legend). The trends are computed as running medians in bins of 0.5\,kpc, with a 40 percent overlap, provided that at least 50 stars are available to compute the median. The shaded areas represent the Poisson uncertainty on the trends. The colours, which are associated to $Z$ distances from the plane, are similar if the $|Z|$ range is the same. |
 | Radial gradients for metallicity (top) and \alphaFe\ (bottom) for different distances from the Galactic midplane (in kpc; see the legend). The trends are computed as running medians in bins of 0.5\,kpc, with a 40 percent overlap, provided that at least 50 stars are available to compute the median. The shaded areas represent the Poisson uncertainty on the trends. The colours, which are associated to $Z$ distances from the plane, are similar if the $|Z|$ range is the same. |
 | Vertical gradients for metallicity (top) and \alphaFe\ (bottom), for different Galactocentric radial ranges. The trends are computed as running medians in bins of 0.5\,kpc, with a 40 percent overlap, provided that at least 50 stars are available to compute the median. Shaded areas represent the Poisson uncertainties on the plotted values. |
 | Vertical gradients for metallicity (top) and \alphaFe\ (bottom), for different Galactocentric radial ranges. The trends are computed as running medians in bins of 0.5\,kpc, with a 40 percent overlap, provided that at least 50 stars are available to compute the median. Shaded areas represent the Poisson uncertainties on the plotted values. |
 | Same as Fig.~\ref{fig:radial_gradients}, selecting this time the stars as a function of $Z_{\rm max}$ and plotting the guiding radius (defined as ($R_{\rm apo}+R_{\rm peri}$)/2) instead of the observed radius. |
 | Same as Fig.~\ref{fig:radial_gradients}, selecting this time the stars as a function of $Z_{\rm max}$ and plotting the guiding radius (defined as ($R_{\rm apo}+R_{\rm peri}$)/2) instead of the observed radius. |
 | Same as Fig.~\ref{fig:radial_gradients}, but selecting only the stars with \g $\le 2$. |
 | Same as Fig.~\ref{fig:radial_gradients}, but selecting only the stars with \g $\le 2$. |
 | Galactic map of the Toomre diagrams colour coded according to \meta. The circular dashed line delimits the regions where the thin- and thick-disc stars are dominant. The vertical dashed line, $V_\phi = 0$, separates prograde and retrograde rotating stars. Halo stars seem preferentially located at positive $V_\phi$ in many panels. |
 | Galactic map of the velocity distribution $V_Z$ vs.\ $V_\phi$ of giant stars (\g $< 3.5$) with $|Z|< 1$ kpc belonging to the Medium Quality sample. The objects are shown, from left to right, in three Galactocentric distance ranges: $6 |
 | Velocity distribution $V_Z$ vs.\ $V_\phi$ of the Medium quality sample for $|Z|< 1$ and $11 |
 | Galactic map of the velocity distribution $V_Z$ vs.\ $Z$ of the Medium Quality sample for 5.25 < R < 11.25 kpc. From left to right, the radial range is shown in three rings at R = 6.25, 8.25, and 10.25 kpc, each of 2 kpc in width. From top to bottom: Normalised density distribution, $Z-V_Z$ plane coloured as a function of median $V_R$, $V_\phi$, and $\Delta$\meta. |
 | Velocity distribution $V_\phi$ vs.\ $R$ for RGB stars within $|Z|<1$~kpc and $\phi<0$ (left panels) and $\phi> 0$ (right panels). Top panels: Distribution of the overdensity $\Delta N$ (see text). Middle panels: Distribution colour coded according to median metallicity. Bottom panels: Residual metallicity, $\Delta$\meta . Black lines show the known ridges from \citet{Ramos:2018}. |
 | Velocity distribution $V_\phi$ vs.\ $R$ for RGB stars within $|Z|<0.5$~kpc colour coded according to residual \alphaFe, $\Delta$\alphaFe. Black lines show the known ridges from \citet{Ramos:2018}. |
 | Velocity distribution $V_\phi$ vs.\ $R$ for massive giants within $|Z|<1$~kpc. Top panel: Density distribution of the sample. Middle panel: Distribution colour coded according to median metallicity. Bottom panel: Residual metallicity, $\Delta$\meta\ (see text). Black lines shows the known ridges from \citet{Ramos:2018}. |
 | Galactic map of the \alphaFe\ vs. \meta\ distribution of the High Quality sample colour coded according to median $V_\phi$. |
 | Density map in the ($L_Z$, $E$) diagram for the \gspspec\ sample. Dashed ellipses represent the contours of regions discussed in Sect.~\ref{Sec:Dynamics}. The shaded area corresponds to pairs ($L_Z$, $E$) with no physical meaning, in which the upper boundary (solid black line) implies perfect circular orbits. |
 | Zoomed-in version of the area enclosed by grey rectangles in Fig.~\ref{Fig_ELz_dens} imposing the selection criteria described in \citet{Koppelman_et_al19}. The colour code is saturated in the high-density regions to emphasise the details of the selected areas. No solar neighbourhood area is selected in this figure because it would contain no stars due to the applied selection criteria. |
 | Distribution of median metallicities (left panel) and $\alpha-$element enrichment with respect to iron (right panel) in the energy-angular momentum ($E$, $L_Z$) plane for the General sample stars without those sources with \g<0.5. The coloured ellipses illustrate the selected areas associated with \Gaia-Sausage-Enceladus (black), Thamnos (magenta), the Helmi stream (red), Sequoia (orange), and the solar neighbourhood sample (white). |
 | \alphaFe\ versus \meta\ diagram for all the stars contained in the regions shown in Fig.~\ref{Fig_ELz_dens} that satisfy the \textit{Medium Quality} selection criteria. The colour code represents the vertical component of the angular momentum $L_Z$. The density plot in the background corresponds to the \textit{Medium Quality} subsample of solar neighbourhood stars. |
 | Distribution of globular cluster stars in the $E$ vs. $L_Z$ diagram (coloured symbols). In the left panel, each cluster is denoted by a different colour and symbol, while in the right panel the colour code represents the metallicity. The density plot in the background corresponds to the General sample. |
 | Distribution of \alphaFe\ abundances with respect to \meta\ for the subsample of GCs with more reliable abundances. Error bars are based on the abundance dispersion within the cluster. A metallicity offset of 0.1~dex with respect to the literature is observed and corrected. Globular cluster stars are generally in the low-S/N regime of the \gspspec\ sample and need more deblending corrections of their spectra due to the crowding. The colour code reflects the GC $L_Z$ median values in solar units. In the background, a density plot with the RGB stars sample distribution is presented. |
 | Distribution of the General sample in the $J_R-L_Z$ diagram colour coded according to density (upper panels), median maximum distance above the Galactic plane $Z_{\rm max}$ (second panels), median metallicity (third panels), and median \alphaFe\ (lower panels). The grey boxes in the left panels indicate the areas for which a zoomed-in version is shown in the right column. The contour lines of the zoomed density plot are included in the right column as a visual reference, while the tentative positions of the ridges are denoted by the dashed lines. Bins with less than ten stars are omitted in the zoomed density plot to enhance the gradient in the colour code. The position of the LSR at ($J_R$, $L_Z$)$=$($0$, $L_{\odot}$) is denoted by the star symbol. |
 | Distributions of \NFe, \MgFe, \SiFe, \SFe, \CaFe\ and \TiFe\ (in each row, respectively) as a function of \meta. The colour bars encode: stellar density (col.~1), median maximum vertical distance to the plane (col.~2), median azimuthal velocity (col.~3), and median eccentricity (col.~4), per cell of 0.04~dex in \meta\ and\ per 0.02~dex in \XFe. The number of selected stars is indicated in the lower left corner of the panels of the first column. |
 | Same as Fig.~\ref{Fig:F7-1} but for \CrFe, \NiFe,\ and \CeFe. |
 | Galactic radial metallicity and [$\alpha$/Fe] gradients traced by open clusters. Top: Cluster \meta\ values as a function of their Galactocentric distance $R$. Clusters are marked by circles colour coded according to their age. The grey shaded areas represent the 68\%\ and 95$\%$ confidence intervals of the linear models resulting from the Bayesian regression, while the black dashed line traces the most probable model. Bottom: Cluster [$\alpha$/Fe] values as a function of their Galactocentric distance $R$. Symbol colours and shaded areas are the same as those in the top panel. |
 | Age dependence of the Galactic metallicity gradient traced by open clusters in the [M/H]--$R$ (blue dots) and [M/H]--r$_{\rm guid}$ (red dots) diagrams. |
 | Kinematic features in the radial metallicity distribution as traced by open clusters. Top: Distribution of open clusters in the V$_{\rm \phi}$--$R$ diagram. The 332 open clusters with [M/H] estimation are shown as grey dots. The red area shows the kernel density estimate of that sample. The Galactic ridges identified by \citet{Ramos:2018} are plotted as in Fig. \ref{FigureKinematics-Vphi-R}. Middle: Locally weighted scatterplot smoothing (LOWESS) regression of cluster V$_{\rm \phi}$ as a function of $R$ (solid line). The shaded area shows the 90$\%$ confidence interval of the LOWESS functions obtained by sampling within the uncertainties of the two variables. Bottom: Residuals between the cluster [M/H] values and the metallicities predicted by the radial metallicity gradient as in Table~\ref{Tab:posteriors_tab} as a function of $R$. As in the middle panel, the solid line shows the LOWESS function and the shaded area shows its 90$\%$ confidence interval. |
 | Galactic map of the fractional residuals between trigonometric and Bayesian distances. {\it Left panel:} full ACS. {\it Right panel:} the same but for the Medium Quality chemical abundances, ACS$_{\rm MQ}$, subsample. |
 | Galactic map of the fractional residuals between trigonometric and Bayesian distances. {\it Left panel:} full ACS. {\it Right panel:} the same but for the Medium Quality chemical abundances, ACS$_{\rm MQ}$, subsample. |
 | Fractional residuals as a function of trigonometric distances ($r_\varpi$). The red line shows the median of the residuals, while the yellow curves trace the 16\% and 84\% quantiles. {\it Left panel:} Full ACS. {\it Right panel:} ACS$_{\rm MQ}$. |
 | Fractional residuals as a function of trigonometric distances ($r_\varpi$). The red line shows the median of the residuals, while the yellow curves trace the 16\% and 84\% quantiles. {\it Left panel:} Full ACS. {\it Right panel:} ACS$_{\rm MQ}$. |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Same as Fig.~\ref{Fig.lb2} but for \alphaFe . |
 | Illustration of the impact of different calibrations on the observed \alphaFe\ vs. \meta\ trends for the samples defined in Sect.~\ref{Sec:selFunc}: HotTO (orange), RGB (grey, with the inner and outer thin disc in pink and green, respectively), and Massive (turquoise) samples. Upper panel: Raw data (no calibration). Left middle panel: Calibrated \alphaFe\ based on \g\ and no \meta\ calibration. This is the solution used throughout the different sections of this article. Right middle panel: Calibrated \alphaFe\ and \meta\ based on \g. Left lower panel: Calibrated \alphaFe\ based on \T\ and no \meta\ calibration. Right left panel: calibrated \alphaFe\ and \meta\ based on \T. |
 | Illustration of the impact of different calibrations on the observed \alphaFe\ vs. \meta\ trends for the samples defined in Sect.~\ref{Sec:selFunc}: HotTO (orange), RGB (grey, with the inner and outer thin disc in pink and green, respectively), and Massive (turquoise) samples. Upper panel: Raw data (no calibration). Left middle panel: Calibrated \alphaFe\ based on \g\ and no \meta\ calibration. This is the solution used throughout the different sections of this article. Right middle panel: Calibrated \alphaFe\ and \meta\ based on \g. Left lower panel: Calibrated \alphaFe\ based on \T\ and no \meta\ calibration. Right left panel: calibrated \alphaFe\ and \meta\ based on \T. |
 | Illustration of the impact of different calibrations on the observed \alphaFe\ vs. \meta\ trends for the samples defined in Sect.~\ref{Sec:selFunc}: HotTO (orange), RGB (grey, with the inner and outer thin disc in pink and green, respectively), and Massive (turquoise) samples. Upper panel: Raw data (no calibration). Left middle panel: Calibrated \alphaFe\ based on \g\ and no \meta\ calibration. This is the solution used throughout the different sections of this article. Right middle panel: Calibrated \alphaFe\ and \meta\ based on \g. Left lower panel: Calibrated \alphaFe\ based on \T\ and no \meta\ calibration. Right left panel: calibrated \alphaFe\ and \meta\ based on \T. |
 | Galactic distribution $(R,Z)$ of 4\,682\,659 stars of the General sample with good astrometric parameters, i.e. not duplicated sources with RUWE $ < 1.4$. Sources are colour coded according to the mean $V_\phi$ (left panel) and $\sigma_{Vz}$ (right panel). |
 | Galactic distribution $(R,Z)$ of 4\,682\,659 stars of the General sample with good astrometric parameters, i.e. not duplicated sources with RUWE $ < 1.4$. Sources are colour coded according to the mean $V_\phi$ (left panel) and $\sigma_{Vz}$ (right panel). |
 | Velocity distribution $V_Z$ vs.\ $V_\phi$ for the Medium Quality stars with good astrometric parameters, $10 |
 | Kiel diagrams of the individual abundances samples. The colour bars show the number of stars per 50~K by 0.05~dex bin. |