The Bochum Survey of the Southern Galactic Disk: III. Complete Data Release

Abstract

The Southern Galactic Disk Survey (GDS) monitored a mosaic of 268 fields along a $6^\circ$-wide stripe in the southern Galactic disk with simultaneous observations in $r'$ and $i'$ ($7^\mathrm{m} \lesssim r', i' \lesssim 18^\mathrm{m}$) from September 2010 to September 2019. The survey design and data characteristics, as well as first results in $r'i'$, were presented by Haas et al. (2012; Paper I). Hackstein et al. (2015a; Paper II) extended the photometry and analysis process, and introduced the first catalogue including photometry of all 268 fields in $UBVr'i'z'$ and $r'i'$ light curves comprising up to 272 observations per field made between September 2010 and May 2015. Here we describe our custom-made observational scheduler and conclude the GDS with $r'i'$ light curves of up to 407 observations per field until September 2019 and $UBVz'$ light curves for a fraction of the fields. $113\,449$ distinct sources are identified as variables. Together with Paper II, we identified $77\,592$ variables that are not listed in either the International Variable Star Index (VSX) or the cross-match catalogue by Gavras et al. (2023). All emerging catalogues, comprising light curves, photometry, and reduced images, are made publicly available via the German Astrophysical Virtual Observatory (GAVO).

Figures (16)

• Figure 1: Observation plan created with AutoSched for IRIS, applied on 16 January 2018, displayed as elevation versus time. Further blue axes frame the time span that fulfils the required observation conditions, specifically target altitudes that lie above $40^{\circ}$ and a limit on the Sun elevation defined for each telescope. The targets' altitude at the scheduled time is indicated by curves. The proposals corresponding to the targets are given in the legend.
• Figure 2: Observation plan created with AutoSched for RoBoTT, applied on 24 January 2018, displayed as elevation versus time, with specifications as in Figure \ref{['fig:obs_plan_iris']}.
• Figure 3: GDS $r'$ field coverage.
• Figure 4: GDS $i'$ field coverage.
• Figure 5: Offset of GDS $r'$ from SDSS $r_\mathrm{s}$ (left) and GDS $i'$ from SDSS $i_\mathrm{s}$ (right) as a function of SDSS $r_\mathrm{s}-i_\mathrm{s}$ colour for the physically plausible $r_\mathrm{s}-i_\mathrm{s}$ colour range of $-1^\mathrm{m}$ to $5^\mathrm{m}$ for 69 292 sources in $r'$ and 45 046 in $i'$ with clean photometry flags in the SDSS; offsets obtained by least squares fitting of the data in the respective plotted range are indicated by red dashed lines.