Technology

SDSS-V will combine new, innovative technologies with well-vetted existing infrastructure to support the demands of its ambitious scientific program. Below, we give a brief overview of a few of these technologies.

Among the hardware assets being carried over from earlier SDSS generations are several dedicated workhorse components:

Robotic Focal Positioners

To meet the requirements for SDSS-V’s rapid exposures and high target densities, we will replace the current SDSS plug-plate fiber system on both telescopes with a robotic fiber positioning system (FPS). Each of these systems will include 500 robotic positioners, 300 of which will hold a fiber each for the BOSS and APOGEE spectrograph, and 200 of which will hold just a BOSS fiber. The FPS also includes all of the cameras and controllers needed for stable guiding and data acquisition.

The FPS robots can account for atmospheric refraction more easily than drilled plates can, which expands the observing window for a particular target configuration and boosts the survey efficiency. The fiber reconfiguration time is reduced from ~20 minutes (the time it takes to change a plug-plate) to ~2 minutes, and target list modifications can be done on a much shorter timescale to accommodate transients and other targets of opportunity.


Testing prototypes of SDSS-V's fiber positioning robots. See a video of them in action <a href="https://youtu.be/jV3Uz_C8W0c">here</a>!
Testing prototypes of SDSS-V's fiber positioning robots. See a video of them in action here!

Fabry-Perot Interferometer

SDSS-V will install a Fabry-Perot Interferometer in both of the APOGEE spectrographs to monitor the variable spectral drift from instrument flexing and dithering. Projections suggest this will improve the already-impressive RV precision of APOGEE spectra from approximately 100 m/s to less than 75 m/s, and much less than 75 m/s for bright sources. This precision will produce substantially expanded science returns in searches for low-mass stellar and planetary companions, including around TESS planet host candidates.

LVM Instrumentation Suite

The Local Volume Mapper will use a brand-new system to enable its wide-field integral field spectroscopy. Building on SDSS-IV’s existing MaNGA technology, SDSS-V will construct a large integral-field unit based on lenslet-array coupled, tightly packed, abuttable bundle of ~2000 fibers.

Spectrographs

This mega-bundle of fibers will feed three brand-new spectrographs at Las Campanas Observatory. Based on the DESI instrument design, each multi-channel spectrograph has a resolution of R~4,000 over a wide optical range (λ~0.36-1 μm).

Small Telescope Suite

The new spectrographs will be fed by fibers from a suite of new small telescopes (D<1 meter). The details of this array are still being finalized, but the goal is to enable high spatial resolution spectroscopy on a wide variety of star-formation regions throughout the Milky Way and Local Group.