The Kavli Institute for Cosmological Physics (KICP) at the University of Chicago will host The Dark Energy Spectrometer workshop on May 30-31 to discuss DESpec, a conceptual next generation dark energy project to enable massive spectroscopic surveys in the southern hemisphere. It would naturally synergize with the Dark Energy Survey (DES), which will start taking data later this year, and with LSST in the longer term. The goal of this meeting is to review past and present work on DESpec and to make plans for how to proceed. We will briefly review the current state of the instrument design and then identify the next steps in the project, including describing the R&D necessary to proceed with theory, survey strategy, and instrument definition. The goal of the workshop will be to begin to assemble the DESpec team, define the project's mission statement, and plan how to proceed in the coming year.

"The Dark Energy Survey Upgrade" (DES Upgrade) is a conceptual next generation dark energy project. It will build on the success of DES and DECam and will provide a powerful spectroscopic follow-up system for sources in the Southern hemisphere discovered by DES and LSST, greatly enhancing the scientific return of both of these large-scale surveys. The project would provide enhanced constraints on dark energy, enable radial baryon acoustic oscillations and redshift-space distortion measurements, provide constraints on neutrino masses, and provide spectroscopic redshifts for millions of objects in the Southern hemisphere. The observations will be made possible by DESpec, a new multi-fiber optical spectrograph for the CTIO Blanco 4-meter telescope. Conceived as an upgrade to the Dark Energy Camera once the Dark Energy Survey is complete, DESpec will take advantage of the recently deployed DECam infrastructure at CTIO. The new instrument will be interchangeable with DECam, will share most of the DECam corrector optics, and will feature a focal plane with ~4000 robotically positioned optical fibers feeding multiple high-throughput, moderate resolution (R~3000) spectrometers.

The DOE is at present working on their long-term strategy for future dark energy experiments and is now forming plans for a workshop to be held as early as June 2012. The NOAO Portfolio Review will issue their report to the NSF on the program on about the same timescale, and that presents the next chance for NOAO to start the competitive process of obtaining new instruments for their telescopes.



While these upper level discussions progress, DESpec scientists are working on the next steps for the DES upgrade: to further develop the science goals, to refine the survey strategy so that it meets the science goals, and to ensure that the DESpec instrument can perform the survey. In doing so, we will put together the team that can successfully carry out this important project.



DESpec collaborators currently include scientists and engineers in the US, the UK, Spain, and Australia. Some have already received monetary resources to work on the problem. We welcome new collaborators and ideas to further the scientific goals of the project.