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The Greenland Telescope The Greenland Telescope Thomas R. Greve What is the GLT? - A brief history US proto-type antenna for ALMA Designed and build by VERTEX (2000-2004) Atacama Large Millimeter/submillimeter Array (ALMA) What is the GLT? - A brief history US proto-type antenna for ALMA Designed and build by VERTEX (2000-2004) Awarded to Academia Sinica (TW) and Smithsonian Astrophysical Observatorty (US) by National Science Foundation in 2011 (value 10M$) Atacama Large Millimeter/submillimeter Array (ALMA) What is the GLT? - Currents partners & budget • NSF: ~22M$ (local infrastructure) • SAO: ~10M$ (support buildings) • ASIAA: ~14M$ (telescope facility) What is the GLT? - Specifications • 12m radio telescope, optimised for observations at sub-mm wavelengths • Cassegrain system with 15 arcminute field of view • Currently located at Thule Airbase →Greenland Summit (~2022). • Summit: N72.5 W38.5, altitude 3200m. Excellent atmospheric conditions for sub-mm observations What is the GLT? - Specifications • 12m radio telescope, optimised for observations at sub-mm wavelengths • Cassegrain system with 15 arcminute field of view • Currently located at Thule Airbase →Greenland Summit (~2022). TARGET: SUMMIT STATION• Summit: GREENLAND N72.5 W38.5, altitude 3200m. Excellent atmospheric conditions for !N!72.5,!W!38.5,!al-tude:!3200!m! sub-mm observations What is the GLT? - Observations and current instrumentation • 2016: Arrival in Thule • 2017: First light • 2018: first 230GHz fringes between GLT and ALMA • 2018: 350GHz VLBI testing • Participating in EHT observations since 2018 First image ever of a black hole - historic discovery! Danish GLT Steering Group www.greenlandtelescope.dk Current members • Thomas Greve (DAWN, DTU Space) • Georgios Magdis (DAWN, DTU Space) • Jes Jørgensen (Starplan, NBI) • Lars Kristensen (Starplan, NBI) • Marianne Vestergaard (Dark, NBI) • Jørgen Peder Steffensen (Ice and Climate, NBI) National coordination Science/ Logistics Funding Instrumentation National coordination - Activities so far Year ‘zero’ Sep 2018 • Renewed Danish interest in the GLT, sparked by DTU Space pitch for GLT science sent to IDA (Instrument center for Danish Astrophysics). Jan 2019 • Talks with Johannes Staguhn (NASA) about bringing the GISMO camera to the GLT Feb 2019 • DTU-DAWN and NBI-Starplan arranges GLT meeting in Copenhagen with participation of TW and US partners. • Talks with Jørgen Peder Steffensen on moving GLT to Greenland Summit • Danish GLT Steering Group is formed • www.greenlandtelescope.dk is launched Apr 2019 • Press conference at DTU Space on EHT / M87 black hole discovery. Lots of national media attention on the EHT and GLT • Danish Minister of Research requests a personal briefing on black holes the next day at NBI Aug 2019 • Paul Ho visits DK to discuss Danish involvement (logistics, instrumentation) Dec 2019 • GLT/GISMO meeting at DAWN-DTU. Everyone is welcome! Science / Instrumentation Science Instrumentation • Gas accretion onto black holes, • GISMO 2mm camera active galactic nuclei • Heterodyne high-frequency • Galaxy formation and evolution receivers • Star formation and interstellar • Instrumentation development and medium pathfinder instruments Science / Instrumentation GISMO installation • 128 pixel TES bolometer camera optimised for 2mm observations (PI: Staguhn, NASA) • Proven concept at IRAM 30m telescope • Some technical challenges fitting GISMO to the GLT but seems solvable • Technical discussion and planning have begun -- regular telecons • Will require structural changes to GLT receiver cabin. • Will require opening up the Nazmyth focus of the GLT Science / Instrumentation A GLT-GISMO extragalactic survey • Probe the large scale structure of the • Unique opportunity for extragalactic early Universe. Identity the most survey of unprecedented area and massive galaxies ~1Gyr after Big Bang depth • Can be done from Thule prior to • Map North Ecliptic Field (Euclid Dep Summit move Field). Rich ancillary data sets Galaxies: z=6.5-7.3 7.3-9.0 z=5 DM density simulation (Springer+05) Dec(deg) Logistics - Moving the telescope to summit Skis under the telescope! • Jørgen Peder Steffens (Ice & Climate, NBI) in charge of this. • 6 skis. Each ski weighs 1.2ton. Dimensions 4.52m × 1.10m. • Make use of existing US traverse train at Thule for transportation of GLT parts to Summit. • EGRIP camp will move to Summit for rendevouos with GLT. • EGRIP: camp while construction GLT and GLT facilities • EGRIP: provide manpower and machinery for site preparation and GLT assembly. • Time-frame: 2023-2024 Logistics - Moving the telescope to summit Skis under the telescope! • Jørgen Peder Steffens (Ice & Climate, NBI) in charge of this. • 6 skis. Each ski weighs 1.2ton. Dimensions 4.52m × 1.10m. • Make use of existing US traverse train at Thule for transportation of GLT parts to Summit. • EGRIP camp will move to Summit for rendevouos with GLT. • EGRIP: camp while construction GLT and GLT facilities • EGRIP: provide manpower and machinery for site preparation and GLT assembly. • Time-frame: 2023-2024 Logistics - GLT assembly and camp Summit camp • EGRIP camp will move to Summit for rendevouos with GLT. • EGRIP: camp while construction GLT and GLT facilities • EGRIP: provide manpower and machinery for site preparation and GLT assembly. • Time-frame: 2023-2024 Funding Sources • Danish Center for Instrumentation (Small) • Carlsberg Infrastructure Research Grant (Medium) • Danmarks Frie Forskningsfond (Medium) • Villum Fonden (Medium) • Maersk (Large) • Other Funding Sources • Danish Center for Instrumentation (Small) • Carlsberg Infrastructure Research Grant (Medium) • Danmarks Frie Forskningsfond (Medium) • Villum Fonden (Medium) • Maersk (Large) • Other Pending applications • Carlsberg Infrastructure Research Grant (1.4MDKK. PI: Greve). To fund transport, installation and commissioning of GISMO onto GLT in Thule. Time-frame: 2020-2022. Funding Sources • Danish Center for Instrumentation (Small) • Carlsberg Infrastructure Research Grant (Medium) • Danmarks Frie Forskningsfond (Medium) • Villum Fonden (Medium) • Maersk (Large) • Other Planned applications • Maersk (15-20MDKK; NBI-DTU lead). To fund transport, construction of GLT at Summit. How do we ensure DTU Leadership? Areas • GLT construction phase (DTU Engineering) • Geodynamics, icesheet (DTU Space, Rene Forsberg) • GLT powered by wind energy (DTU Wind) • Remote sensing, monitoring (DTU Drone Center, Michael Linden Vørnle) • Astronomy research (DTU Space) • Future instrumentation (DTU Space) • Other? The GLT is a great opportunity for Denmark Scientific interests Strategic national interests • Major partnership in a sub-mm • Research in the Artic / First telescope would be a game- observatory in the Arctic changer for Danish astronomy. • Geopolitics / national security • Danish participartion in the EHT consortium • Major educational and outreach potential in Denmark and Greenland • Instrumentation development • Strengthening ties between • Other (Ice, geodesy, remote Denmark and Greenland sensing, …) A permanent astronomical Arctic Major grant observatory in Greenland with (15-20MDKK) Denmark as a major partner. The GLT is a great opportunity for Denmark.
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