A Submillimeter and CMBR Observatory for the South Pole Antony A. Stark Committee on Astronomy and Astrophysics 10 November 1998 1/18/2019

Toward a large single-dish user facility at the South Pole Current status of submillimeter and CMBR operations at Pole Site testing results The proposed South Pole 10m telescope The SP 10 in the context of modern astronomy 1 1/18/2019

A large, wide-field single-dish submillimeter-wave telescope, operating as a user-facility instrument on the Antarctic plateau, is uniquely capable of significant advances in observational cosmology and studies of protogalaxies and protostars. 2 1/18/2019

South Pole Station occupies a square mile surrounding the geographic South Pole population: 210 people November-February, 35 people February-October ~250 flights per year of LC130 aircraft, each ~16 tons SPSM (South Pole Station Modernization) in progress, completion in 2004 Research support 150 to 300 KW electrical power supplied continuously for science 10,000 liters LHe each year 3500 m2 heated laboratory space intermittent internet and TDRSS communications 3 1/18/2019

Cosmic Microwave Background Studies current projects are 3rd generation Bell Labs, UCSB, White Dish Python I-VI Viper and DASI excellent results obtained at 1° to 3° angular scales progress requires move to smaller scales and higher frequency (/D < 310-4  D > 3 m) measurement of acoustic peak separation of primary and secondary anisotropy SZ effect always significant at small scales requires high frequency & high sensitivity (best possible site) measurement of SZ velocity effect, velocity dispersion of clusters 1/18/2019

4 AST/RO Operations 4th year of continuous operation just completed 1st year as a user facility summer maintenance and upgrades 20 astronomers and engineers, typical 3 week visit winter operations 1 winter-over scientist operational over 85% of time for astronomy 4 1/18/2019

Submillimeter-wave site testing South Pole is world’s best-characterized submm site South Pole weather annual average temperature –49C, low –82C median winter PWV = 0.22 mm no high winds, no rain, no dust, no bugs better than Mauna Kea, Chajnantor in sub-mm opacity (but comparable in mm opacity) identical long-term sub-mm projects (at high source elevation) proceed 110 faster than MK, 4.5 faster than Chajnantor sky noise (variations in sky emissivity) very low water vapor less dominant source of opacity than at other sites 5 1/18/2019

Considerations for for future Submillimeter-wave telescopes SP station infrastructure cannot support a large array case for single-dish success of SCUBA large (~104 element) bolometer arrays are under development intrinsically high bandwidth, low noise low parts count per pixel diameters of 10 m (passive) to 30 m (active) possible at Pole large focal plane arrays require large field of view new type of sub-mm telescope offset Gregorian can be designed for both wide-field sub-mm and CMBR use 6 1/18/2019

Conclusion large single-dish sub-mm and CMBR user-facility telescope, operated by an international consortium, is possible at South Pole sensitive, wide-field sub-mm imager “finder scope” for MMA large-scale statistics of sub-mm background radiation high frequency CMBR at l ~ 103, velocity dispersion of clusters ongoing SPSM construction makes an immanent decision desirable approval soon would allow coordination with SPSM, completion of telescope construction soon after completion of SPSM 1/18/2019