This paper describes a new Heterodyne Array Receiver Program (HARP) and Auto‐Correlation Spectral Imaging System (ACSIS) that have recently been installed and commissioned on the James Clerk Maxwell Telescope. The 16‐element focal‐plane array receiver, operating in the submillimetre from 325 to 375 GHz, offers high (three‐dimensional) mapping speeds, along with significant improvements over single‐detector counterparts in calibration and image quality. Receiver temperatures are ∼120 K across the whole band, and system temperatures of ∼300 K are reached routinely under good weather conditions. The system includes a single‐sideband (SSB) filter so these are SSB values. Used in conjunction with ACSIS, the system can produce large‐scale maps rapidly, in one or more frequency settings, at high spatial and spectral resolution. Fully sampled maps of size can be observed in under 1 h. The scientific need for array receivers arises from the requirement for programmes to study samples of objects of statistically significant size, in large‐scale unbiased surveys of galactic and extra‐galactic regions. Along with morphological information, the new spectral imaging system can be used to study the physical and chemical properties of regions of interest. Its three‐dimensional imaging capabilities are critical for research into turbulence and dynamics. In addition, HARP/ACSIS will provide highly complementary science programmes to wide‐field continuum studies and produce the essential preparatory work for submillimetre interferometers such as the Submillimeter Array (SMA) and Atacama Large Millimeter/Submillimeter Array (ALMA).
The James Clerk Maxwell Telescope (JCMT) Telescope Control System (TCS) received significant upgrades to provide new observing capabilities to support the requirements of the SCUBA-2 instrument. The core of the TCS is the Portable Telescope Control System (PTCS), which was developed through collaboration between the Joint Astronomy Centre and the Anglo-Australian Observatory. The PTCS provides a well-designed virtual telescope function library that simplifies these sorts of upgrades. The TCS was previously upgraded to provide the required scanning modes for the JCMT heterodyne instruments. The heterodyne instruments required only relatively simple raster or boustrophedon patterns, which are basically composed of multiple straight-line scans to cover a rectangular area. The most recent upgrades built upon those heterodyne scanning modes to satisfy the SCUBA-2 requirements. With these upgrades, the TCS can scan the telescope in any pattern that can be described as a continuous function of time. This new capability has been utilized during the current SCUBA-2 on-sky commissioning phase to scan the telescope in a variety of patterns (Lissajous, pong, ellipse, and daisy) on the sky. This paper will give a brief description of the PTCS, provide information on the selection of the SCUBA-2 scanning modes, describe the changes to the TCS that were necessary to implement the new scanning modes, and show the performance of the telescope during SCUBA-2 commissioning.
The current study evaluated adolescent patients' enjoyment of and knowledge gained from game-based learning compared with an interactive lecture format on the topic of mood disorders. It was hypothesized that game-based learning would be statistically more effective than a lecture in knowledge acquisition and satisfaction scores. A pre-post design was implemented in which a convenience sample of 160 adolescent patients were randomized to either a lecture (n = 80) or game-based (n = 80) group. Both groups completed a pretest/posttest and satisfaction survey. Results showed that both groups had significant improvement in knowledge from pretest compared to posttest. Game-based learning was statistically more effective than the interactive lecture in knowledge achievement and satisfaction scores. This finding supports the contention that game-based learning is an active technique that may be used with patient education. [Journal of Psychosocial Nursing and Mental Health Services, 56(2), 29-36.].
This paper describes the key design features and performance of HARP, an innovative heterodyne focal-plane array receiver designed and built to operate in the submillimetre on the James Clerk Maxwell Telescope (JCMT) in Hawaii. The 4x4 element array uses SIS detectors, and is the first sub-millimetre spectral imaging system on the JCMT. HARP provides 3-dimensional imaging capability with high sensitivity at 325-375 GHz and affords significantly improved productivity in terms of speed of mapping. HARP was designed and built as a collaborative project between the Cavendish Astrophysics Group in Cambridge UK, the UK-Astronomy Technology Centre in Edinburgh UK, the Herzberg Institute of Astrophysics in Canada and the Joint Astronomy Centre in Hawaii. SIS devices for the mixers were fabricated to a Cavendish Astrophysics Group design at the Delft University of Technology in the Netherlands. Working in conjunction with the new Auto Correlation Spectral Imaging System (ACSIS), first light with HARP was achieved in December 2005. HARP synthesizes a number of interesting features across all elements of the design; we present key performance characteristics and images of astronomical observations obtained during commissioning.
The steady improvement in telescope performance at UKIRT and the increase in data acquisition rates led to a strong desire for an integrated observing framework that would meet the needs of future instrumentation, as well as providing some support for existing instrumentation. Thus the Observatory Reduction and Acquisition Control (ORAC) project was created in 1997 with the goals of improving the scientific productivity of the telescope, reducing the overall ongoing support requirements, and eventually supporting the use of more flexibly scheduled observing. The project was also expected to achieve this within a tight resource allocation. In October 1999 the ORAC system was commissioned at the United Kingdom Infrared Telescope (UKIRT).ORAC took a systems level approach to its overall design in creating an advance Preparation system, an Observatory Control System and a pipelined on-line Data Reduction system. Much of the system was designed and implemented using Object Oriented techniques and current software technologies, and attempts were made to re-use software from other projects where possible and appropriate. The design implemented is highly modular allowing future upgrading if necessary. The opportunity was also taken to implement the use of software "instrument apertures" on UKIRT. We describe the ORAC system, some of the design methods and comment on some of the issues to be tackled when attempting to use other people's software and in managing a distributed project.
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