scholarly journals Brightness temperature for radio sources

2007 ◽  
Vol 3 (S245) ◽  
pp. 245-246
Author(s):  
J. H. Fan ◽  
Y. Huang ◽  
Y. Liu ◽  
Y. Gao ◽  
T. X. Hua ◽  
...  
Keyword(s):  
Brightness Temperature ◽  
Radio Astronomy ◽  
Radio Sources ◽  
University Of Michigan ◽  
Astronomy Observatory ◽  
Radio Astronomy Observatory ◽  
Brightness Temperatures ◽  
The University

AbstractIn this work, using the database of the university of Michigan Radio Astronomy Observatory (UMRAO), we determined the brightness temperatures, TB for a sample of 167 radio sources. The value of TB is in a range of log TB(K) = 10.46 to 20.08, which suggested that the boosting factors are in a range of δ = 0.41 to 41.26.

scholarly journals Radio variability properties for sources at multi-frequencies

2007 ◽  
Vol 3 (S245) ◽  
pp. 251-252
Author(s):  
Y. Liu ◽  
J. H. Fan ◽  
H. G. Wang
Keyword(s):  
Time Series ◽  
Radio Astronomy ◽  
Power Spectral Analysis ◽  
Light Curves ◽  
University Of Michigan ◽  
Astronomy Observatory ◽  
Period Analysis ◽  
Radio Astronomy Observatory ◽  
Power Spectral ◽  
The University

AbstractUsing three radio databases of the university of Michigan Radio Astronomy Observatory (UMRAO), the National Radio Astronomy Observatory (NRAO), and the Metsähovi Observatory, we analyzed the radio light curves by the power spectral analysis and CLEANest method in search for possible periodicity. Multiple periods are found in some sources at multi-frequencies. We adopted the wavelets for period analysis of unevenly sampled time series to search for the evolution of the parameters (period, amplitude) of possible periodicities. Some possible variation of these parameters are found.

scholarly journals Observations of Some Radio Sources Previously Identified with Clusters of Galaxies

1967 ◽  
Vol 20 (6) ◽  
pp. 725
Author(s):  
HM Tovmassian ◽  
IG Moiseev
Keyword(s):  
Radio Telescope ◽  
Radio Astronomy ◽  
Astronomical Observatory ◽  
Radio Sources ◽  
Clusters Of Galaxies ◽  
Astronomy Observatory ◽  
Radio Astronomy Observatory ◽  
The University ◽  
East West

The positions of 33 radio sources previously identified with distant clusters of galaxies were remeasured more accurately to check the identifications. Observations were made at 1410 and 2650 MHz with the 210 ft radio telescope of the Australian National Radio Astronomy Observatory at Parkes, and at 408 MHz with the east-west arm of the Mills Cross at the Molonglo Radio Astronomical Observatory of the University of Sydney. It was found that 21 sources are situated within 5 min of arc of the centres of the corresponding clusters.

scholarly journals The early technical development of the VLA

1991 ◽  
Vol 131 ◽  
pp. 160-164 ◽  
Author(s):  
George W. Swenson
Keyword(s):  
Radio Astronomy ◽  
Technical Development ◽  
Large Array ◽  
Astronomy Observatory ◽  
University Of Illinois ◽  
Very Large Array ◽  
Radio Astronomy Observatory ◽  
Leave Of Absence ◽  
The University ◽  
Academic Year

In the spring of 1964, having qualified for a sabbattical leave from the University of Illinois and having recently completed two years as Chairman of the Visiting Committee of the National Radio Astronomy Observatory, I inquired of the NRAO staff as to whether a desk and possibly some augmentation of my University half-salary might be available at Green Bank for the following academic year. Instead I was invited to join the staff as a fulltime employee and to take a coordinating role in the development of the “very large array” as Chairman of the Design Committee. The University granted me a year’s leave of absence which eventually stretched to four years.

scholarly journals The Parkes Catalogue Of Radio Sources Declination Zone 0° To ?20°

1966 ◽  
Vol 19 (6) ◽  
pp. 837 ◽  
Keyword(s):  
Radio Astronomy ◽  
Radio Sources ◽  
Astronomy Observatory ◽  
Radio Astronomy Observatory

This paper gives details of 628 radio sources between declinations 0� and - 20� compiled from observations made at 408 Mc/s with the 210 ft reflector at the Australian National Radio Astronomy Observatory, Parkes, N.S.W.

scholarly journals Surveys of Radio Sources at 5 GHz

1977 ◽  
Vol 74 ◽  
pp. 63-74
Author(s):  
I. I. K. Pauliny-Toth
Keyword(s):  
Flux Density ◽  
Radio Astronomy ◽  
Radio Sources ◽  
Astronomy Observatory ◽  
Max Planck ◽  
Radio Astronomy Observatory ◽  
Density Relation ◽  
Strong Source ◽  
Optical Identifications ◽  
5 Ghz

A number of surveys have been carried out at a frequency of 5 GHz at the National Radio Astronomy Observatory (NRAO) and at the Max-Planck-Institut für Radioastronomie (MPIfR), with the aim of determining the number-flux density relation for the sources detected and also of obtaining their radio spectra and optical identifications. The surveys fall into two categories: first, the strong source (S) surveys, which are intended in due course to cover the whole northern sky and to be complete above a flux density of about 0.6 Jy; second, surveys of limited areas of sky down to lower levels of the flux density.

scholarly journals The VSOP Survey: final aggregate results

2006 ◽  
Vol 2 (S238) ◽  
pp. 357-358
Author(s):  
R. Dodson ◽  
S. Horiuchi ◽  
W. Scott ◽  
E. Fomalont ◽  
Z. Paragi ◽  
...  
Keyword(s):  
Brightness Temperature ◽  
Radio Astronomy ◽  
Radio Sources ◽  
Survey Paper ◽  
Brightness Temperatures ◽  
Future Space ◽  
Magnetic Spectrum ◽  
Electro Magnetic ◽  
5 Ghz ◽  
Galactic Radio

AbstractIn February 1997 the Japanese radio astronomy satellite HALCA was launched to provide the space-borne element for the VSOP mission. HALCA provided linear baselines three-times greater than that of ground arrays, thus providing higher resolution and higher AGN brightness temperature measurements and limits. Twenty-five percent of the scientific time of the mission was devoted to the “VSOP survey” of bright, compact, extra-galactic radio sources at 5 GHz. A complete list of 294 survey targets were selected from pre-launch surveys, 91% of which were observed during the satellite's lifetime.The major goals of the VSOP Survey are statistical in nature: to determine the brightness temperature and approximate structure, to provide a source list for use with future space VLBI missions, and to compare radio properties with other data throughout the electro-magnetic spectrum. All the data collected have now been analysed and is being prepared for the final image Survey paper. In this paper we present details of the mission, and some statistics of the images and brightness temperatures.

scholarly journals The Parkes Catalogue of Radio Sources Declination Zone +20° to +27°

1968 ◽  
Vol 21 (3) ◽  
pp. 377 ◽  
Author(s):  
AJ Shimmins ◽  
GA Day
Keyword(s):  
Radio Astronomy ◽  
Radio Sources ◽  
Astronomy Observatory ◽  
Radio Astronomy Observatory

This paper gives details of 397 radio sources between declina.tions + 200 and +270 which were compiled from a finding survey made at 635 MHz with the 210 ft reflector at the Australian National Radio Astronomy Observatory, Parkes, N.S.W.

scholarly journals The VLB array: a new geophysical tool

1988 ◽  
Vol 128 ◽  
pp. 445-451 ◽  
Author(s):  
Edward B. Fomalont
Keyword(s):  
Radio Astronomy ◽  
Environmental Parameters ◽  
Virgin Islands ◽  
Radio Sources ◽  
Astronomy Observatory ◽  
Radio Astronomy Observatory ◽  
Long Baseline ◽  
The Usa ◽  
Very Long Baseline Array

The National Radio Astronomy Observatory is constructing a Very Long Baseline Array (VLBA) consisting of ten antennas across the USA, between Hawaii and the Virgin Islands. The array will be a dedicated instrument for producing milliarcsecond images of radio sources. However, exciting geophysical applications of the array are obvious and, furthermore, detailed geodetic, astrometric and environmental parameters are necessary for the VLBA to achieve its full sensitivity, resolution and positional capabilities.

Sign in / Sign up

Export Citation Format

Share Document