juliensimon/gaia-dr3-chemical-cartography

Gaia DR3化学制图目录提供了约560万颗恒星的银河轨道参数，这些参数源自Gaia天体测量、径向速度以及径向速度光谱仪（RVS）的化学丰度数据。每颗恒星在银河系引力势中的轨道通过作用积分（Jr、Jz、Jphi）、轨道极值（rapo、rperi、zmax）、偏心率以及当前在柱面和笛卡尔银河中心坐标系中的相空间位置来完整表征。所有参数均提供了三个置信边界（中位数、上、下1-sigma），这些边界通过轨道积分传播了来自自行、视差和径向速度测量的不确定性。作用量是银河考古学中最强大的坐标，因为在平滑势中，它们在许多轨道周期内是守恒的（或近似守恒）。不同的恒星族占据作用量空间中独特且不重叠的区域：薄盘集中在（Jr≈0, Jz≈0, |Jphi|≈1500–2000 kpc·km/s）附近，厚盘在相似的Jphi下向更高的Jr和Jz扩散，来自被破坏的矮星系的吸积晕星在特征性的（Jr, Jz, Jphi）位置形成运动学流，而原位晕则占据高偏心率（ecc>0.7）的逆行轨道。将轨道作用量与来自同一光谱的化学丰度（[Fe/H]、[α/Fe]）相结合，能够对银河系的组装历史进行化学动力学剖析——这是化学制图的主要科学目标。这是迄今为止为银河系恒星组编的最大运动学目录，相较于之前的巡天如RAVE DR6（约450,000颗恒星）、GALAH DR4（约600,000颗恒星）或APOGEE DR17（约700,000颗恒星），其规模提升了一个数量级。托姆雷图（sqrt(vz² + vR²) vs vφ）清晰地区分了薄盘、厚盘和晕族。zmax与rapo的散点图或偏心率分布揭示了银河系中原位物质和吸积物质的相对贡献。该数据集适用于表格分类和表格回归任务。The Gaia DR3 Chemical Cartography catalog provides galactic orbital parameters for approximately 5.6 million stars derived from Gaia astrometry, radial velocities, and chemical abundances from the Radial Velocity Spectrometer (RVS). Each stars orbit in the Milky Ways gravitational potential is fully characterized by action integrals (Jr, Jz, Jphi), orbital extremes (rapo, rperi, zmax), eccentricity, and current phase-space position in both cylindrical and Cartesian Galactocentric coordinates. All parameters are provided with three confidence bounds (median, upper, lower 1-sigma) that propagate uncertainties from proper motion, parallax, and radial velocity measurements through the orbital integration. Actions are the most powerful coordinates for galactic archaeology because they are conserved (or nearly so) over many orbital periods in a smooth potential. Different stellar populations occupy distinct, non-overlapping regions of action space: the thin disk concentrates near (Jr ≈ 0, Jz ≈ 0, |Jphi| ≈ 1500–2000 kpc·km/s), the thick disk spreads to higher Jr and Jz at similar Jphi, accreted halo stars from disrupted dwarf galaxies form kinematic streams at characteristic (Jr, Jz, Jphi) loci, and the in-situ halo occupies high-eccentricity (ecc > 0.7) retrograde orbits. Combining orbital actions with chemical abundances ([Fe/H], [α/Fe]) from the same spectra enables chemo-dynamical dissection of the Galaxys assembly history — the primary science goal of chemical cartography. This is the largest kinematic catalog ever assembled for Milky Way stars, representing an order-of-magnitude improvement over previous surveys such as RAVE DR6 (~450,000 stars), GALAH DR4 (~600,000 stars), or APOGEE DR17 (~700,000 stars). The Toomre diagram (sqrt(vz² + vR²) vs vφ) cleanly separates thin disk, thick disk, and halo populations. Scatter plots of zmax vs rapo or ecc distributions reveal the relative contributions of in-situ and accreted material across the Galaxy. This dataset is suitable for tabular classification, tabular regression tasks.