The SDSS-V focal plane fiber-positioning hardware and survey strategy were designed around the core science cases, whose target densities — and relative infrared vs optical needs — vary dramatically across the sky, from Baade’s window to high-latitudes. This inevitably leaves unallocated (or “open”) fibers.
In response to this SDSS-V opened a (series of) collaboration-internal “open fiber proposal” call. DR18 reflects the 30 target category proposals that resulted from the first call in November 2020. Boundary conditions for these proposals were that:
- the science goals — complementing core science — could be reached with single 15~minute exposures using either the APOGEE (infrared) or BOSS (optical) spectrographs;
- the targeting information was freely available to all SDSS-V members, and a target selection function could be specified.
Much of the proposed science fell into three broad categories:
- more extensive surveying of AGNs and X-ray sources across the sky;
- broader stellar physics, in particular binary star physics, across the color-magnitude diagram (CMD);
- studying the Milky Way’s stellar halo and metal-poor population, which (intentionally) had not been a focus of the Galactic Genesis program.
These programs were reviewed by an consortium-internal independent panel in early 2021, and their target categories are listed in the table below.
| Carton Name | Description | Instrument | Available Targets1 |
|---|---|---|---|
| openfibertargets_nov2020_3 | Bright Eclipsing Binaries | BOSS | 34689 |
| openfibertargets_nov2020_5 | Extremely Metal-Poor (EMP) Stars, Galactic Halo (SkyMapper [Fe/H]<-3 candidates) | BOSS | 39099 |
| openfibertargets_nov2020_6a | Galactic Halo in S (SkyMapper BHBs) | BOSS | 50611 |
| openfibertargets_nov2020_6b | Galactic Halo in S (SkyMapper distant and/or metal-poor RGBs) | BOSS | 340436 |
| openfibertargets_nov2020_6c | Galactic Halo in S (SkyMapper metal-poor dwarfs) | BOSS | 890043 |
| openfibertargets_nov2020_8 | Young Galactic Disk, Young/Massive Stars Spectra of stars in coeval moving groups | BOSS/APOGEE | 704638 |
| openfibertargets_nov2020_9 | F Star Physics, Young/Massive Stars Spectra of 10% of the F-stars TESS lightcurves | BOSS/APOGEE | 1197354 |
| openfibertargets_nov2020_10 | Binaries, RVs in chemically anomalous stars one addl. epoch for APOGEE stars with anomalous X/H | BOSS/APOGEE | 917 |
| openfibertargets_nov2020_11 | All QSOs/AGN, Quasars Second Epochs for SDSS-I/II Quasars observed only once | BOSS | 39684 |
| openfibertargets_nov2020_12 | Binaries, Close Binary Stars one additional epoch for binaries from APOGEE | BOSS/APOGEE | 33577 |
| openfibertargets_nov2020_14 | Binaries, MS-WD Binaries spatially unresolved Ms+WD pairs | BOSS | 10798 |
| openfibertargets_nov2020_15 | Open Cluster Survey X/H / age gradients from open clusters (all *>50% member) | BOSS/APOGEE | 177185 |
| openfibertargets_nov2020_17 | Census of all YSO <500pc, Young/Massive Stars get spectra (RV, logg, Teff) for all YSOs within 500pc | BOSS | 32891 |
| openfibertargets_nov2020_18 | All QSOs/AGN, Hard X-ray Sources get 10,000 hard-band selected X-ray sources (eROSITA is softer) | BOSS | 10012 |
| openfibertargets_nov2020_19a | TESS 2min cadence, Gaia IDs | BOSS/APOGEE | 224773 |
| openfibertargets_nov2020_19b | TESS 2min cadence, Legacy Survey IDs | BOSS/APOGEE | 1605 |
| openfibertargets_nov2020_19c | TESS 2min cadence, PanSTARRS IDs | BOSS/APOGEE | 1615 |
| openfibertargets_nov2020_22 | Binaries, Ellipsoidal Binaries Very close binaries with ellipsoidal TESS light curve variations | APOGEE | 28408 |
| openfibertargets_nov2020_24 | Chemodynamics in the Solar neighborhood get spectra of all K/M metal-rich dwarfs 250pc<D<500pc: 6D phase-space & Fe/H | BOSS | 1323442 |
| openfibertargets_nov2020_25 | Local Halo Survey, Gaia-selected get all K/M metal-poor/halo stars within 1kpc | BOSS/APOGEE | 293741 |
| openfibertargets_nov2020_26 | All QSOs/AGN, Quasar Winds Long-term spectroscopic mentoring of quasar winds through additional epochs on previously well-observed BAL quasars | BOSS | 2105 |
| openfibertargets_nov2020_27 | All QSOs/AGN, All Bright Quasars All QSO candidates G<20 WISE-colors & optical information | BOSS | 814963 |
| openfibertargets_nov2020_28a | Outer Galactic Halo, Distant K giants tracers of the Galactic halo beyond the Solar neighborhood | BOSS | 73627 |
| openfibertargets_nov2020_28b | Outer Galactic Halo, Distant BHBs tracers of the Galactic halo beyond the Solar neighborhood | BOSS | 49900 |
| openfibertargets_nov2020_28c | Outer Galactic Halo, Distant RRLs tracers of the Galactic halo beyond the Solar neighborhood | BOSS | 51234 |
| openfibertargets_nov2020_29 | Extra-tidal Globular Cluster stars get at dynamics of GC disruption: tidal debris candidates stars | BOSS/APOGEE | 107688 |
| openfibertargets_nov2020_30 | All QSOs/AGN – JWST North Ecliptic Pole Time Domain | BOSS | 237 |
| openfibertargets_nov2020_31 | RAVE Cross Calibration APOGEE Spectra of RAVE (~GDR#) stars, across large range of Teff, logg, [M/H] | APOGEE | 62275 |
| openfibertargets_nov2020_32 | Binaries, Wide MS-WD binaries spectra for WD-MS binaries from El-Badry & Rix | BOSS/APOGEE | 34230 |
| openfibertargets_nov2020_33 | All QSOs/AGN, Variability-Selected AGN and Blazars Confirmation and Characterization of Variability-selected AGN, QSOs, and Blazars | BOSS | 22250 |
| openfibertargets_nov2020_34a | CMD tiling – nonvariables | BOSS | 8701166 |
| openfibertargets_nov2020_34b | CMD tiling – variables | BOSS | 643546 |
| openfibertargets_nov2020_35a | Galactic Halo, Metal-poor Halo Metal-poor stars selected with infrared Color-selected metal-poor stars across sky | BOSS | 345721 |
| openfibertargets_nov2020_35b | Galactic Halo, Metal-poor Halo SkyMapper metal-poor stars, Ca HK Color-selected metal-poor stars across sky | BOSS | 52696 |
| openfibertargets_nov2020_35c | Galactic Halo, Metal-poor Halo SAGES metal-poor stars, Ca HK Color-selected metal-poor stars across sky | BOSS | 7521 |
| openfibertargets_nov2020_46 | LAMOST Multi-epoch Stars revisit all stars G<18 that have >=2 epochs with LAMOST | BOSS | 663835 |
| openfibertargets_nov2020_47a | SDSS-V LMC Genesis, SDSS-V Magellanic Genesis: RGB Contiguous-area extension of SDSS-V population mapping of LMC | BOSS | 278987 |
| openfibertargets_nov2020_47b | SDSS-V LMC Genesis, SDSS-V Magellanic Genesis: AGB Contiguous-area extension of SDSS-V population mapping of LMC | APOGEE | 27731 |
| openfibertargets_nov2020_47c | SDSS-V LMC Genesis, SDSS-V Magellanic Genesis: Massive BOSS Contiguous-area extension of SDSS-V population mapping of LMC | BOSS | 1000 |
| openfibertargets_nov2020_47d | SDSS-V LMC Genesis, SDSS-V Magellanic Genesis: Massive APOGEE Contiguous-area extension of SDSS-V population mapping of LMC | APOGEE | 1000 |
| openfibertargets_nov2020_47e | SDSS-V LMC Genesis, SDSS-V Magellanic Genesis: Symbiotic Contiguous-area extension of SDSS-V population mapping of LMC | APOGEE | 24 |
| openfibertargets_nov2020_1000 | Stellar Clusters, Bulge Globular Clusters & Globular Cluster Stars Get APOGEE spectra for all hitherto unobserved BGCs and spectra for as many GC stars as feasible (>50% membership) | BOSS/APOGEE | 102172 |
| openfibertargets_nov2020_1001a | Binaries, Wide Binaries Spectra for wide binaries, for calibration, abundance evolution, ages, WD masses, etc. | BOSS/APOGEE | 81303 |
| openfibertargets_nov2020_1001b | Binaries, Wide Binaries Spectra for wide binaries, for calibration, abundance evolution, ages, WD masses, etc. | BOSS | 10545 |