Galactic Radio Astronomy

'Galactic Radio Astronomy' was chosen as the subject of this Symposium, which was held in conjunction with the IAU General Assembly that took place in Sydney in August 1973, largely because it is a very suitable Southern Hemisphere topic. This results in part from the advantages of a southern location in studying the Galaxy and in part from the long association of Australia with radio astronomy. Following the General Assembly, the Symposium was held at the Surf air Inter­ national Hotel in Maroochydore, Queensland, from 3 to 7 September, 1973. The conference participants were effectively isolated from the rest of the world during the Symposium, and the excellent spring weather and geographical situation led to the development of an unusually good rapport. The Symposium was sponsored by Commissions 40, 33, and 34. The Organizing Committee was composed of A. H. Barrett (chairman), J. E. Baldwin, D. S. Heeschen, F. J. Kerr, J. Lequeux, S. W. McCuskey, P. G. Mezger, B. Y. Mills, Yu. N. Parijskij, B. J. Robinson, H. van der Laan, and H. F. Weaver. The Local Committee, consisting ofB. J. Robinson, N. G. Seddon, and P. J. Kelly, looked after the arrangements in very fine style. The Symposium was supported financially by the IAU, the Australian Academy o~ Science, the CSIRO Division of Radiophysics, Union Carbide Australia Limited, and the Science Foundation for Physics within the University of Sydney.

Preface.- List of Participants.- 1 / The Interstellar Medium.- The Observational Evidence for an Intercloud Medium (Review).- A Modern Look at ‘Interstellar Clouds’ (Review).- Properties of Neutral Hydrogen Clouds.- Free Electrons Outside H ii Regions (Review).- Line Absorption Studies of the Interstellar Gas Near 1015 Hz (Review).- On Microwave Recombination Lines from H i Regions (Abstract).- Two New Recombination-Line Results.- The Galactic Electron Distribution from a Pulsar Survey.- Heating and Ionization of the Interstellar Medium (Review).- Theoretical Calculations of Interstellar Cloud Formation.- Expanding Shells of Neutral Hydrogen as Birthplaces of Stellar Associations.- Interstellar Molecules - Theory (Review).- Extended OH Emission at 1720 MHz (Summary).- The Observed Characteristics of the Local Magnetic Field (Review).- A High-Resolution Polarization Survey of the North Polar Spur.- The Chemical Composition and Distribution of Interstellar Grains (Review).- The Gas-to-Dust Ratio in the Galaxy.- Absorption Characteristics of Dust in the Lyman Continuum Region (Abstract).- Spectrum of Galactic Background Radiation (Summary).- Galactic Background Radiation at 2 cm and Thermal Electrons in the Galaxy.- Thermal and Maser Phenomena in Rotationally Excited OH (Abstract).- 2 / Galactic H ii Regions.- Recent Radio Observations of Galactic H ii Regions (Review).- High-Resolution Radio Observations of a Giant H ii Region in Cygnus.- Radio Observations of H ii Regions in M33 (Read by H. J. Habing).- The H ii Regions of M31.- The Brightness Distribution of Ori A at 4.1 mm in the 101–000 Line of Para-Formaldehyde and in the Continuum.- Large-Scale Expansion in the Carina Nebula (Abstract).- Decimeter-Wavelength Studies of Recombination Lines.- Optical Observations of Ionized Gas in External Galaxies (Review).- Distribution of Dust in the Orion Nebula (Abstract).- Infrared Emission from H ii Regions (Review).- Maser Sources in H ii Regions (Review).- Magnetic Fields in OH Maser Clouds.- On the First Southern-Sky H2O Masers Observed at Itapetinga, Brazil.- Time Scales and Masses of OH-Emission Regions (Summary).- OH Observations Near the Reflection Nebulae NGC 2068 and NGC 2071.- H ii Regions: Some Theoretical Developments (Review).- 3 / Supernova Remnants.- Observational Aspects of Supernova Remnants (Review).- Supernova Remnants: Can a Fossil H ii Region Be Formed as the Result of a Supernova Explosion?.- Polarization Observations of Supernova Remnants.- High-Resolution Observations of Galactic Nonthermal Sources at 160 MHz.- A 160-MHz Map of Cas A.- Westerbork Observations of the Galactic Supernova Remnants IC 443 and Tycho (Read by H. J. Habing).- 21-cm Absorption Study of Extended Supernova Remnants.- The Birthplaces of Pulsars.- New Results on Supernova Remnants (Summary; read by Yu. Parijskij).- 4 / Stellar and Circumstellar Sources.- Radio Continuum Observations of Stellar Sources (Summary) (Review).- Stellar X-Ray Sources (Review).- Radio Outbursts from Cygnus X-3.- Infrared and X-Ray Variability of Cyg X-3.- Measurements on Planetary Nebulae.- Fine Structure in Planetary Nebulae.- Radio Observations of IR/OH/H2O Stars (Review).- The Infrared Properties of Circumstellar OH/IR and H2O/IR Sources (Review).- Some High-Velocity Sources of 1612 MHz OH Emission.- 5 / The Galactic Center.- Infrared Radiation from the Galactic Center (Review).- Radio Continuum and Recombination Line Studies of the Galactic Center (Review).- The Galactic Center at 408 MHz.- Occultation Observations of the Galactic Center Region at 327 MHz.- 21-cm Line Studies of the Galactic Center Region (Review).- Kinematics of Molecules at the Galactic Centre (Review).- Observations of the J = 6 to 5 Line of OCS in Sgr B2.- The Galactic Centre (Review: Summary and Concluding Remarks).- 6 / Large-Scale Galactic Structure.- Current Problems in 21 cm Line Studies of the Large-Scale Structure of the Galaxy (Review).- Some Aspects of Galactic Structure Derived from the Berkeley Low Latitude Survey of Neutral Hydrogen (Invited Paper).- Progress Report on the Maryland-Green Bank Galactic 21-cm Line Survey.- A Simple Interpretation of the ‘Rolling Motions’.- High Velocity Neutral Hydrogen Clouds (Review).- The Magellanic Stream.- The Large-Scale Structure of Local H i, Dust, and Galactic Radio Continuum (Invited Paper).- Low- and Intermediate-Velocity Hydrogen at Positive Galactic Latitudes.- Continuum Radio Emission and Galactic Structure (Review).- The Bonn 408 MHz Survey.- Author Index.