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Title: SCUBA-2: on-sky calibration using submillimetre standard sources
Authors: Jessica T. Dempsey, Per Friberg, Tim Jenness, Remo P. J. Tilanus, Holly S. Thomas, Wayne S. Holland, Dan Bintley, David S. Berry, Edward L. Chapin, Antonio Chrysostomou, Gary R. Davis, Andrew G. Gibb, Harriet Parsons, E. Ian Robson

SCUBA-2 is a 10000-bolometer submillimetre camera on the James Clerk Maxwell Telescope (JCMT). The instrument commissioning was completed in September 2011, and full science operations began in October 2011. To harness the full potential of this powerful new astronomical tool, the instrument calibration must be accurate and well understood. To this end, the algorithms for calculating the line-of-sight opacity have been improved, and the derived atmospheric extinction relationships at both wavebands of the SCUBA-2 instrument are presented. The results from over 500 primary and secondary calibrator observations have allowed accurate determination of the flux conversion factors (FCF) for the 850 and 450 micron arrays. Descriptions of the instrument beam-shape and photometry methods are presented. The calibration factors are well determined, with relative calibration accuracy better than 5 per cent at 850 microns and 10 per cent at 450 microns, reflecting the success of the derived opacity relations as well as the stability of the performance of the instrument over several months. The sample-size of the calibration observations and accurate FCFs have allowed the determination of the 850 and 450 micron fluxes of several well-known submillimetre sources, and these results are compared with previous measurements from SCUBA.

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Title: A new era of wide-field submillimetre imaging: on-sky performance of SCUBA-2
Authors: Jessica T. Dempsey, Wayne S. Holland, Antonio Chrysostomou, David S. Berry, Daniel Bintley, Edward L. Chapin, Simon C. Craig, Iain M. Coulson, Gary R. Davis, Per Friberg, Tim Jenness, Andy G. Gibb, Harriet A. L. Parsons, Douglas Scott, Holly S. Thomas, Remo P.J. Tilanus, Ian Robson, Craig A. Walther

SCUBA-2 is the largest submillimetre wide-field bolometric camera ever built. This 43 square arc-minute field-of-view instrument operates at two wavelengths (850 and 450 microns) and has been installed on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. SCUBA-2 has been successfully commissioned and operational for general science since October 2011. This paper presents an overview of the on-sky performance of the instrument during and since commissioning in mid-2011. The on-sky noise characteristics and NEPs of the 450 and 850 micron arrays, with average yields of approximately 3400 bolometers at each wavelength, will be shown. The observing modes of the instrument and the on-sky calibration techniques are described. The culmination of these efforts has resulted in a scientifically powerful mapping camera with sensitivities that allow a square degree of sky to be mapped to 10 mJy/beam rms at 850 micron in 2 hours and 60 mJy/beam rms at 450 micron in 5 hours in the best weather.

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Dusty Stellar Nurseries from the Dark Side of a Galaxy

One of the world's most powerful cameras, SCUBA-2 is producing its first detailed images of our neighbouring galaxies, revealing previously undetected vast pockets of star formation where the next generation of stars is being created. The light from these stars is usually obscured by dust, but at the sub-millimetre wavelengths that the camera is designed for, these dust lanes actually glow brightly. The images are revealed in the week of the 25th anniversary of the James Clerk Maxwell Telescope (27 April 2012) on which SCUBA-2 is mounted.
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Camera sheds light on early Universe

University astronomers are helping to lead a study of how some of the oldest stars in the Universe were formed.
A team of scientists from the UK, Canada and Netherlands are examining star formation across the Universe, looking back in time to when the universe was still young.
The consortium is using the most powerful camera of its type to observe light at wavelengths beyond the visible light spectrum, which cannot be seen by eye.

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A major effort is under way to observe the Universe in its most vibrant epoch.
UK, Canadian and Dutch astronomers are looking back 10 billion years in time to see galaxies when they produced stars a thousand times faster than anything in the local cosmos today.
The work employs a new camera recently fitted to the James Clerk Maxwell Telescope in Hawaii.

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Camera uses intense cold to peer into deep space

The heart of the SCUBA-2 astronomy camera unveiled Tuesday at the top of Mauna Kea summit in Hawaii is cooled to just one-tenth of one degree above absolute zero.
Scientists from the University of B.C. designed and constructed the electronics that take data from a camera that can discern objects in deep space by detecting long wavelengths of light that are invisible to humans and even sophisticated optical cameras. But in order to "see" these very faint so-called submillimetre wavelengths, the camera must be cooled to -273.05 C to eliminate interference from local earthbound energy sources, making it "the coldest cubic metre in the universe," according to UBC astronomer Mark Halpern.

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James Clerk Maxwell Telescope starts survey of the submillimeter sky
Astronomers on Mauna Kea are beginning a new survey of the universe at the James Clerk Maxwell Telescope.
The JCMT Legacy Survey will give astronomers a new perspective on the origins of the planets, stars, galaxies and even the universe itself, according to a news release from the Joint Astronomy Center in Hilo.

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Astronomers using the James Clerk Maxwell Telescope (JCMT) in Hawaii are making new discoveries about the origins of the planets, stars and galaxies with the start of a new survey to map the Universe.
The JCMT Legacy Survey, made up of 7 projects, makes use of two sophisticated new instruments - SCUBA-2 and HARP which will allow the astronomers to detect and probe clouds of cold dust associated with the mysterious earliest phases of the formation of galaxies, stars and planets.

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SCUBA-2
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Today (21 February 2008) the Science and Technology Facility Councils UK Astronomy Technology Centre (UK ATC) at the Royal Observatory Edinburgh shipped its biggest and most complex ever instrument. The giant camera known as SCUBA-2 will be transported to the James Clerk Maxwell Telescope (JCMT) on top of a 14,000 foot mountain in Hawaii where it is expected to make major discoveries related to the origins of galaxies, stars and planets.
Rather than detecting visible light, SCUBA-2 will detect sub millimetre radiation, which is sensitive to the heat emitted by extremely cold dust in the Universe. This material is associated with the mysterious earliest phases of the formation of galaxies, stars and planets, hitherto largely undetectable. Typically the dust is at temperatures of about -200 Celsius and so detecting its extremely weak emissions presents a huge technological challenge.

"Sub millimetre astronomy is a relatively new science and one where the UK has led the world over the past two decades. Our latest camera is the most powerful yet: SCUBA-2 on the JCMT should detect the equivalent of the heat from a candle on the surface of the Moon" - Dr Wayne Holland, the project leader at the UK ATC.

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Scientists at the Royal Observatory have unveiled a revolutionary new astronomical camera which can see deeper into outer space than ever before.
The 14 million Scuba 2 device is being prepared to be shipped out to Hawaii at the end of September where it will begin work detecting undiscovered planets and examining how stars form.

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