Millimetre and Submillimetre Astronomy


Book Description

The millimetre and submillimetre spectral region (300 to 3000 Ilm or 1000 to 100 GHz) was until recently one of the few spectral regimes not fully opened up for astronomical studies. Thanks both to improvements in detectors and receivers and to the construction of large telescopes at high altitude sites this situation is improving very rapidly. Three major telescopes have been built recently and are coming into operation during 1987 and 1988, namely the 15m James Clerk Maxwell Telescope (JCMT) and the lOAm Caltech Submillimetre Observatory (CSO) telescope, both located on Mauna Kea, Hawaii, and the 15 m Swedish -ESO telescope (SEST) in Chile. Because a very wide range of astronomical problems can be tackled with these major new facilities there is a great deal of interest from the many potential new users anxious to become familiar with this rapidly developing field. During 1986 it became clear to British and Dutch astronomers involved in planning the commissioning and operation of the JCMT, that a summer school in this field would greatly benefit the potential and actual JCMT user community. With financial support from the SERC and supplemented by a grant from the ZWO, the Summer School on 'Millimetre and Submillimetre Astronomy' was held at Stirling University from June 21 to 27, 1987.







Submillimetre Astronomy


Book Description

G. M. Bernstein, M. L. Fischer, and P. L. Richards Department of Physics, University of California Berkeley, California 94720, U. S. A. J. B. Peterson Department of Physics, Princeton University Princeton, New Jersey 08540, U. S. A. T. Timusk Department of Physics, McMaster University Hamilton, Ontario L8S 4M1 , Canada ABSTRACT. Recent measurements of the diffuse background at millimeter wavelengths indicate no departure from a Planck spectrum near the peak of the blackbody curve. Anisotropy measurements indicate no structure, at the 2% level, in the recently detected submillimeter excess. We report here the results of an April 1987 balloon flight of an instrument designed to measure the spectrum of the cosmic background radiation from 1 mm to 3 mm. A description of the instrument can be found in Peterson, Richards, and Timusk (1985). Modifications were made to the apparatus and experimental procedure in order to identify and reduce systematic errors. Results from the latest flight indicate that two effects hamper the interpretation of the data. These systematic effects will be described in detail in a forthcoming publications; they are probably responsible for the non-Planckian spectrum measured by Woody and Richards (1981). Attempts to remove the systematic effects from our data yield the upper limits to the CBR brightness temperature in 4 bands from 1 mm to 3 mm. There is no evidence for an excess of radiation near the 2. 8 K blackbody peak.




Development of Coherent Detector Technologies for Sub-Millimetre Wave Astronomy Observations


Book Description

The thesis describes the development of receiver technologies for sub-millimetre astronomy instruments, focusing on high performance coherent cryogenic detectors operating close to the superconductor gap frequency. The mixer chip which comprises the SIS devices, fed by a unilateral finline and matching planar circuits was fabricated on 15 micron silicon substrate using the recently developed Silicon-On-Insulator (SOI) technology. This offered broadband IF and RF performance, with fully integrated on-chip planar circuits resulting in an easily reproducible mixer chip and a simple mixer block. An important consequence of this design is that it can be extended to the supra-THz region and making the fabrication of multi-pixel heterodyne arrays feasible. The extension of the operation of major telescopes such as ALMA, APEX and the GLT from single pixel to large format arrays is the subject of extensive research at present time since it will allow fast mapping combined with high resolution of the submillimetre sky. The technology described in this thesis makes a major contribution to this effort.










The Spatialities of Radio Astronomy


Book Description

The Spatialities of Radio Astronomy examines the multidisciplinary overlap between the spatial disciplines and the studies of science and technology through a comparative study of four of the world’s most important radio telescopes. Employing detailed analysis, historical research, interviews, personal observations, and various conceptual manoeuvres, Guy Trangoš reveals the depth of spatial process active at these scientific sites and the territories they traverse. Through the conceptual frameworks of territory, hyper-concentration, and contingency, Trangoš interprets the telescope as exploded across space and time, present in multiple connected sites simultaneously, and active in the production of space. He develops a historiographic and contemporary analysis of the Atacama Large Millimeter/submillimeter Array (ALMA, Chile); the Five-hundred-meter Aperture Spherical radio Telescope (FAST, China); the Arecibo Observatory (Puerto Rico); and the MeerKAT/SKA (South Africa). These case studies are global exemplars of the different spatial transformations that occur through science. Their relationships to surrounding communities and landscapes reveal deeper constitutional processes embodied in each institutional and spatial form. This book spans the modern history of architecture and science, the studies of science, technology and society, and urban theory. It is of specific interest to architects and designers expanding their analysis of spatial production, scholars in the study of geography, landscape, science, technology, and astronomy, and people fascinated with how these radio telescopes were conceptualised, built, and operate today.




Status and Prospects of Astronomy in Germany 2003-2016


Book Description

This white paper identifies the main issues and major recommendations for German astronomical research. Their implementation will require initiative from all partners and will allow German astronomers and astrophysicists to continuously play a leading role in their field.




Observational Molecular Astronomy


Book Description

Molecular line emissions offer researchers exciting opportunities to learn about the evolutionary state of the Milky Way and distant galaxies. This text provides a detailed introduction to molecular astrophysics and an array of useful techniques for observing astronomical phenomena at millimetre and submillimetre wavelengths. After discussing the theoretical underpinnings of molecular observation, the authors catalogue suitable molecular tracers for many types of astronomical regions in local and distant parts of the Universe, including cold gas reservoirs primed for the formation of new stars, regions of active star formation, giant photon-dominated regions and near active galactic nuclei. Further chapters demonstrate how to obtain useful astronomical information from raw telescope data while providing recommendations for appropriate observing strategies. Replete with maps, charts and references for further reading, this handbook will suit research astronomers and graduate students interested in broadening their skill to take advantage of the new facilities now coming online.