We have matched the ultraviolet (UV) sources in GUVcat_AIS with optical databases that have similar depth and wide sky coverage. GUVcat_AIS has Galaxy Evolution Explorer (GALEX) far-UV (FUV, λ _eff ∼ 1528 Å) and near-UV (NUV, λ _eff ∼ 2310 Å) photometry of ≈83million sources, covering 24,788squaredegrees of the sky, with a typical depth of FUV=19.9 and NUV=20.8AB mag. Matches with Gaia and the Sloan Digital Sky Survey (SDSS) databases are presented here. Gaia datarelease2 (DR2), covering the entire GUVcat footprint, detected about one-third of the GUVcat_AIS sources. We found 31,925,294 GaiaDR2 counterparts to 30,024,791 GUVcat_AIS unique sources, with photometry in the GaiaG band and often also in GaiaBP and RP bands; 26,275,572 matches have a parallax measurement, 21,084,628,18,588,140,and16,357,505 have a parallax error less than 50%, 30%, and 20%, respectively. The match with SDSS data release 14 (DR14) yields 23,310,532 counterparts to 22,207,563 unique GUVcat_AIS sources, 10,167,460 of which are pointlike, over a total overlap area of ≈11,100squaredegrees (Bianchi et al. 2019). SDSS adds five optical magnitudes to the UV photometry : u, g, r, i, z, and optical spectra of 860,224 matched sources. We used a match radius of 3″, consistent with previous works, although the positions agree to ≲15 for the majority of (pointlike) matched sources, in order to identify possible multiple matches whose UV flux could be unresolved in GALEX imaging. The catalogs can be trimmed to a tighter match radius using the provided separation. The multiband photometry is used to identify classes of astrophysical objects that are prominent in UV, to characterize the content of the GUVmatch catalogs, where stars in different evolutionary stages, quasi-stellar objects, and galaxies can be separated.

我们将GUVcat _AIS 中的紫外线 (UV) 源与具有相似深度和广阔天空覆盖范围的光学数据库进行了匹配。GUVcat _AIS 拥有 Galaxy Evolution Explorer (GALEX) 远紫外 (FUV, λ _eff ∼ 1528 Å) 和近紫外 (NUV, λ _eff ∼ 2310 Å) 约 8300 万个光源，覆盖 24,788 平方度的天空，具有典型的FUV=19.9 和 NUV=20.8AB mag 的深度。此处提供了与 Gaia 和斯隆数字巡天 (SDSS) 数据库的匹配。Gaia datarelease2 (DR2)，覆盖整个GUVcat足迹，检测到大约三分之一的GUVcat _AIS 源。我们发现 31,925,294 GaiaDR2 对应物与 30,024,791 GUVcat_AIS 独特的来源，在 Gaia G波段进行测光，通常也在 GaiaBP 和 RP 波段进行测光；26,275,572 个匹配具有视差测量值，21,084,628,18,588,140 和 16,357,505 个匹配的视差误差分别小于 50%、30% 和 20%。与 SDSS 数据版本 14 (DR14) 的匹配产生 23,310,532 个对应物与 22,207,563 个独特的GUVcat _AIS 源，其中 10,167,460 个是点状的，总重叠面积约为 11,100 平方度（Bianchi 等人 20,167,460）。SDSS 为紫外光度测量增加了五个光学量级：u , g , r , i , z，以及 860,224 个匹配源的光谱。我们使用了 3 英寸的匹配半径，与之前的工作一致，尽管对于大多数（点状）匹配源，位置同意≲15，以便识别可能的多个匹配，其紫外线通量在 GALEX 成像中可能无法解析。可以使用提供的间隔将目录修剪为更紧密的匹配半径。多波段光度测量用于识别在紫外线中突出的天体物理物体的类别，以表征GUVmatch目录的内容，其中可以分离处于不同演化阶段的恒星、准恒星物体和星系。