Wide field break-out Schlegel - Science in the 2020’s • redshift surveys larger by 10X every 10 years (some combination of wit, luck, money) • lots of projects from 2010 decadal not realized • DESI and PFS not in that table • being done on existing telescopes • better than lots of things that were planned for • No strong reason to design for resolutions less than R~5000 • sky lines in the red • DESI re-design could include IR to 1.3 um (4th arm, 980-12000, Germanium CCDs) • DESI cuold work on Blanco, Calar Alto 4-m, Magellan with existing f/5 corrector • Magelllan f3 correctionr with larger FOV • MMT 6.5-m or SMPT • 6.5-m are very affordable • FOBOS on Keck - but pay penalty for using larger glass • For last decadal, very exhaustive study of 17 existing telescopes -> impact on DESI. Now good time to revisit this (Schelegel and Scholl) • Unconvetional platforms - solar telescopes! F/100 • DOE Cosmic Visions - process for future projects. Key technologies we should be developing • GLAO for LSST, DESI - might be big bang for buck • Germanium CCDs - funded through DOE R&D. SImilar to silicon CCDs - can extend wavelength to 1.35um without as much cryogenic cooling • Low noise readout (<1 photon of read noise) - Skipper CCDs • Fiber positioners, DESI drove costs down 10X, opportunities for more. Not funded through DOE now (no questions) Pat Hall - MSE • fture of CFHT. • Replace dome by one 10% bigger • 11.25 segmented primary • 4332-fiber positionor, 1.5 deg FOV • switchable low or med res spectrographs • see arXiv paper • R=40,000 optical spectrographs - stellar chemical tagging, quasar RM, dwarf galaxies • dedicated spectroscopic facility with 20% PI time • image quaility very good - epxect 0.5” in r-band. Small fibers, lower costs • AAO Sphinx positioners (updated Echidna) • Fibers tilted - some FRD issues, but testing this • R~3300,*360-1300 or R~59000 • France, China, Canda, Australia, Hawaii, India • science team assembled for design reference survey • design review for telescope, dome, spectrographs • Envision Maunakea • $300 M cost casp • both cash and in-kind contiributions needed • each partner will have “shares”, propose and run surveys, • CONSTRUCTION 2022-2026 • access to 74% of LSST footprint • Additional funding needed for operations - don’t have numbers yet. Partners joining late would be feasible Tim Abbot - Blanco spectroscopy • spectrograph that could be used interchanablly with DECAM • to make instruments interchangeable would have to alter DECAM • cooling chain very long/expensive - could this be improved? Good to do anyway! • DESpec reuses decam corrector, 4000 fibers • Table with massively multiplexed fiber systems! • only 2 of techologoies at telescope - suspicous until this happens • fiber robots are the hard part (spectrographs better tested/developed Jeff Newman • How long would science cases take on a wide variety of telescopes? • metric is years of dark time • Surveys • MW halo stars • Local dwarfs and halo streams (low mass DM preturbers) • 100,000 galaxies over 4 skq deg • LSST supernova hosts in deep drilling fields - redshifts for 50,000 SNe • photometric redshift survey - best on large aperture PFS for MSE • MW halo survey - DESI fairly competitive • Local dwarfs best from MGT • Galaxy evolution - yr on DESI • Supernova survey quite easy with anything - DESI twice as fast as TMT/WFOS • Combination of 4-m and something larger could give us options for large variety of science • how could you get all these done with different facilities? Also, dollar cost associated (operations). • Raja: many facilities are using _all_ of these science cases for their funding • Adam - halo survey may be easiest to sell • We should make a table of science cases with the facilities that are ideal, good, not recommended • halo survey - fair amount of spare capacity (not using all fibers). Must vary from instrument to instrment • Raja - unwise to put everything into red giant survey, (but souce density not limiting factor so easy to add other targets) Main seq turn-off stars • Only SN hosts and halo survey don’t saturate fibers • would be great to have a tool that allows us to find most efficient facilties Arjun: -What capabilties do we need - perparory imaging,etc -What role does NOAO play? -Priorities for short and long term investment? What would you like to do, what can you do? Two build teams DESI, LSST - will be ready to move on soon. NOAO has a lot of techncial expertise. Dave S. - this is the year to think about how Blanco might be re-purposed what happens after 2023, not known - can leverage decades of experience on all 6 platforms have invested a lot in modernization How do we engage in projects that want NOAO participation? Juna: basically we have an infinite appetite for spetrsocopy. It would be great to have DESI in North and a copy in the South. Helpful on the operations side. NOAO facilities span broad dynamic range - we’ve got to be using apertures where they are most powerful • Figuring out robot technologies seems like the issue Ben W. - LSST was high priority of last decadal survey, we might decide to do something different Dave Silva - decadal survey will get excited by new science Juna - what are Australians doing? Could imagine 2 MSEs. Pat: They want a wider field, 5 sq deg instead of 1.5. Jay: if you look at future instruments, things that will give you trouble are downstream from the corrector. Schlegel: small re-design of DESI could give NIR arm. Might be very inexpensive in a few years. Juna: robots are a difficult regime, we have been building spectrographs a long time. We have a great design from DESI. What happens if DOE stops investing? Is there a plan for long term stewardship? Schlegel: DOE goes project by project. Juna: Is this a stable partnership? Schegel: for 5 - 10 yr projects as good as anything else Dave S. - NSF not committed to any of telescopes past ~2023. If we want to use these platforms to do good stuff, we have to argue for life cycle cost of supporting them. Arjun: there are 4 four meter telescopes - if science drives you towards them NOAO is here to help you figure out if that is the new path Juna - where is there most money on table for improving BOA? Do you really want to go to south? J Jeff N. - 4MOST will do the same quasar density as DESI. Schlegel - 50% more area for sqrt(N) gain won’t matter. Is there an advantage for Ly-a tomorgraphy? Schelegel: Diminishing returns at about R~20,000, but improvements in CCDs may change this. Arjun: May be some physical limitations from fibers Some itnerest in increasing sample density at z=2 - 5, but uncertaities about targets Jim Fuller: Galactic science - GAIA will have distances to 2 billion stars - get spectra for 100M brightest. Can map out entire galaxy with abundances, masses, ages. Legacy of having this kind of data would be incredible. Arjun: this is one thing we can accomplish in the next decade. • Could calibrate lower res spectra from DESI Jeff: what would you gain from 100M rather than 20M that FORMOST and DESI will do? • DESI 10M - doesn’t reperesent whole population well • Jim F - get everything with GAIA distance • want to map full kinematics structures of streams (Juna - refiniing this case now - really hard, but lots of potential for DM) • Juna galactic archeology is a N^2 process - do gain quite a lot by going to large numbers of stars. Arjun: what is actually practical? • should we abandon 4-m and focus on MSE? • Jeff N. - would be crazy to turn them off in 2024 • Schelgel - do we stay with current NOAO platforms or explore other partnerships. NOAO did go through TSIP supporting instrumentation and giving comunity access - very successful but then zeroed out • Schelgel - Technically Magellan looks like best thing out there • in bounds for MSIP program? • Juna: Has MSIP funded anything over $11M? • Dave S. - lot of discussion within NSF. Looking at mid-scale infrarstructure. Asking for things in $50 - $150M range gives decadal survey more ammunition to encourage NSF to start thinking about this middle ground • Jeff N. - handling of operations funds - how might it change? Dave S. - everyone facing the same issue. Almost a crisis point. • Arjun: things being mission driven now on our 4-m. SDSS has been like this for many years. If the science is strong, possible to fund limited phases of operations. Pathway for getting more focused about science questions. • Dave Silva - projects keep facilties in trust for years • Juna - useful thing about about the SDSS model - its gotta be cutting edge or its gone. • David S - Point is that you need to rejustify things all the time - gotta be on the science • What is the roadmap? How do we work together to make a case for the decadal survey? • Knut - want road map to include answer at various scales - galactic archeology problem - can do great stuff with existing facilties. Greater stuff with DESI like facilties in south. MSE the ultimate machine • Arjun: start with DESI and SDSS-V in south before 2025. Then try to build DESI-2 in south. Ultimately we want stand alone thing on 10-m - maybe MSE? A realistic budgeted plan might be able to endorse studies. • Jay: European concept doesn’t have money - maybe should explore partnership. • Dave Silva - don’t explore partnership model. Focus on capabilties and science objectives. Let others figure out how to fund this. MSE is a lot closer to some of science cases than expected. DESI-S can tackle lots of science cases. • Pat: What science would you do with MSE when it arrives? Join design reference survey. Now is the time to say what the science requires. All interested in galactic structure - should write white paper exploring that vision