Diffraction-limited imaging in the visible at the WHT
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Diffraction-limited imaging in the visible at the WHT Craig Mackay, Institute of Astronomy, University of Cambridge. 22 March 2010: Science with WHT
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Diffraction-limited imaging in the visible at the WHT. Craig Mackay, Institute of Astronomy, University of Cambridge. La Palma & The WHT The LPO is one of the very best sites. The WHT is a good telescope, with negligible dome seeing. La Palma & The WHT - PowerPoint PPT Presentation
Transcript of Diffraction-limited imaging in the visible at the WHT
Diffraction-limited imaging in the visible at the WHT
Craig Mackay,
Institute of Astronomy, University of Cambridge.
22 March 2010: Science with WHT
La Palma & The WHT
• The LPO is one of the very best sites.
• The WHT is a good telescope, with negligible dome seeing.
22 March 2010: Science with WHT
La Palma & The WHT
• The LPO is one of the very best sites.
• The WHT is a good telescope, with negligible dome seeing.
• Competitive instrumentation essential to establishing a real niche.
22 March 2010: Science with WHT
La Palma & The WHT
• The LPO is one of the very best sites.
• The WHT is a good telescope, with negligible dome seeing.
• Competitive instrumentation essential to establishing a real niche.
• Diffraction-limited imaging in visible will fit the bill.
22 March 2010: Science with WHT
Lucky Imaging: The Einstein Cross
• HST/ACS (Left image), Lucky Image on NOT (Right image).
22 March 2010: Science with WHT
• Globular cluster M13 on the Palomar 5m.
• Seeing ~650 mas.
• Used PALMAO + our EMCCD Lucky Camera.
• With 30% selection, ~17% Strehl (I-band) ~40 mas resolution.
• Highest resolution image ever taken in the visible.
Large Telescope Lucky Imaging.
22 March 2010: Science with WHT
14 December 2007: U3A, King’s Lynn
• The Lucky/AO images resolve <40 mas, ~ 3 times Hubble.
Large Telescope Lucky Imaging.
14 December 2007: U3A, King’s Lynn
Large Telescope Lucky.
(From Olivier Guyon, Subaru telescope.
• AO usually needs a bright reference star.
14 December 2007: U3A, King’s Lynn
Large Telescope Lucky.
(From Olivier Guyon, Subaru telescope.
• AO usually needs a bright reference star.
• We are building a new kind of wavefront curvature sensor.
14 December 2007: U3A, King’s Lynn
Large Telescope Lucky.
(From Olivier Guyon, Subaru telescope.
• AO usually needs a bright reference star.
• We are building a new kind of wavefront curvature sensor.
• Much more sensitive than Shack-Hartmann sensors particularly for low-order.
14 December 2007: U3A, King’s Lynn
Large Telescope Lucky.
(From Olivier Guyon, Subaru telescope.
• AO usually needs a bright reference star.
• We are building a new kind of wavefront curvature sensor.
• Much more sensitive than Shack-Hartmann sensors particularly for low-order.
• Can work with reference objects x100-1000 fainter.
• A similar system can now be built now for the WHT.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• A similar system can now be built now for the WHT.
• Will allow a wide range of problems to be tackled that require >HST resolution in visible.
• Examples include globular cluster physics, quasar host galaxies, AGN studies, compact gravitational lenses, MACHO surveys in crowded regions and many others.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• A similar system can now be built now for the WHT.
• Will allow a wide range of problems to be tackled that require >HST resolution in visible.
• Examples include globular cluster physics, quasar host galaxies, AGN studies, compact gravitational lenses, MACHO surveys in crowded regions and many others.
• Also works as high-time resolution instrument.
• Photon-counting CCDs allow limited fields at 1000Hz.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Use a low-order AO system using a curvature sensor.
• On WHT would give resolution of 30-50 milliarcsecs in V to I-bands (HST is ~125 mas).
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Use a low-order AO system using a curvature sensor.
• On WHT would give resolution of 30-50 milliarcsecs in V to I-bands (HST is ~125 mas).
• Selection rate typically 30% to 40%.
• FOV 2000x2000, so 30x30 to 150x150 arcsecs.
• Require reference star of I~18, so ~90% sky coverage.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Use a low-order AO system using a curvature sensor.
• On WHT would give resolution of 30-50 milliarcsecs in V to I-bands (HST is ~125 mas).
• Selection rate typically 30% to 40%.
• FOV 2000x2000, so 30x30 to 150x150 arcsecs.
• Require reference star of I~18, so ~90% sky coverage.
• Already under development in Cambridge with STFC/PPRP grant.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Capital cost ~ £200K, plus ~£300K salaries.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Capital cost ~ £200K, plus ~£300K salaries.
• First light of basic system in 15 months.
• Complete in 24 months (user interface/reduction software is main effort).
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
• Capital cost ~ £200K, plus ~£300K salaries.
• First light of basic system in 15 months.
• Complete in 24 months (user interface/reduction software is main effort).
• Unique capability that really exploits the quality of the La Palma site.
• Opportunity for UK to take a world lead in the only way known to deliver diffraction limited imaging in the visible.
Lucky/AO Imager for the WHT.
22 March 2010: Science with WHT
22 March 2010: Science with WHT
Instrumentation Group Institute of Astronomy
University of Cambridge, UK
