VLBI observations with the Kunming 40-meter radio telescope

2010 ◽  
Vol 10 (8) ◽  
pp. 805-814 ◽  
Author(s):  
Long-Fei Hao ◽  
Min Wang ◽  
Jun Yang
Keyword(s):  
Radio Telescope ◽  
Vlbi Observations

e-VLBI observations of GRB 080409 afterglow with an Australasian radio telescope network

2016 ◽  
Vol 16 (11) ◽  
pp. 164
Author(s):  
Aquib Moin ◽  
Philip G. Edwards ◽  
Steven J. Tingay ◽  
Chris J. Phillips ◽  
Anastasios K. Tzioumis ◽  
...  
Keyword(s):  
Radio Telescope ◽  
Vlbi Observations

scholarly journals Space-VLBI observations of OH masers

2002 ◽  
Vol 206 ◽  
pp. 105-111 ◽  
Author(s):  
Vyacheslav I. Slysh ◽  
Maxim A. Voronkov ◽  
Irina E. Val'tts ◽  
Victor Migenes ◽  
K.M. Shibata ◽  
...  
Keyword(s):  
Brightness Temperature ◽  
Lower Limit ◽  
Radio Telescope ◽  
Angular Resolution ◽  
Main Line ◽  
Radio Telescopes ◽  
Space Radio Telescope ◽  
Vlbi Observations ◽  
Interstellar Scattering

We report on the first space-VLBI observations of the OH masers in two main-line OH transitions at 1665 and 1667 MHz. The observations involved the space radio telescope on board the Japanese satellite HALCA and an array of ground radio telescopes. The maps of the maser region and images of individual maser spots were produced with an angular resolution of 1 mas, which is several times higher than the angular resolution available on the ground. The maser spots were only partly resolved and a lower limit to the brightness temperature 6 × 1012 K was obtained. The masers seem to be located in the direction of low interstellar scattering.

scholarly journals Space Ground Interferometer

1991 ◽  
Vol 131 ◽  
pp. 112-114
Author(s):  
A.I. Savin ◽  
M.B. Zaxon ◽  
L.I. Matveyenko
Keyword(s):  
Radio Telescope ◽  
Circular Orbit ◽  
Vlbi Observations ◽  
Mission Time ◽  
Space Project

AbstractA space project for studying ecological Earth problems is being carried out by means of radio techniques. A 30 m prototype antenna has already been deployed and tested. The radio telescope will be launched in 1994 into a circular orbit haying an altitude 600 km and an inclination of 65°. The planned mission time is ≥ 1.5 year; 25% of this will be available for VLBI observations at wavelengths 6 and 18 cm.

scholarly journals Lunar Occultations of the SiO Masers in RLeo

1994 ◽  
Vol 140 ◽  
pp. 154-155
Author(s):  
J. Cernicharo ◽  
W. Brunswig ◽  
G. Paubert ◽  
S. Liechti
Keyword(s):  
Radio Telescope ◽  
Angular Resolution ◽  
High Angular Resolution ◽  
Linear Antenna ◽  
The Moon ◽  
Moderate Size ◽  
Millimeter Wavelengths ◽  
Vlbi Observations ◽  
The Ideal

VLBI observations show that the SiO maser emitting regions in oxygen-rich stars are very clumpy and that these clumps extend over a few stellar radii (Mclntosh et al. 1987; Colomer et al. 1992). These observations indicate that the ideal instrument for the study of the SiO masers is an interferometer with baselines covering between a few and several hundreds/thousands km. Such an instrument is so far unavailable.A classical way to get high angular resolution and a full beam synthesis with a single telescope of moderate size is through lunar occultations. This observing technique provides the angular resolution of a single linear antenna several kilometers long. However, at millimeter wavelengths the Fresnel fringes produced by the Moon limb as the source under study is occulted have never been observed. We present here the observation with the 30-m IRAM radio telescope of the v=1 J=2-1 line of SiO during an occultation (and reappearance) of R Leo by the Moon.

scholarly journals Very Long Baseline Interferometry Observations Using the Tracking and Data Relay Satellite as an Orbiting Radio Telescope

1988 ◽  
Vol 129 ◽  
pp. 457-458 ◽  
Author(s):  
R. P. Linfield ◽  
G. S. Levy ◽  
J. S. Ulvestad ◽  
C. D. Edwards ◽  
J. F. Jordan ◽  
...  
Keyword(s):  
Radio Telescope ◽  
Very Long Baseline Interferometry ◽  
Geostationary Orbit ◽  
Brightness Temperatures ◽  
Long Baseline ◽  
Vlbi Observations

An antenna in geostationary orbit was used for VLBI observations at 2.3 GHz, in combination with ground antennas in Australia and Japan. 23 of the 25 observed sources were detected on orbiter-ground baselines, with baseline lengths as large as 2.15 earth diameters. Brightness temperatures between 1012 K and 4 × 1012 K were measured for 10 sources.

scholarly journals Performance Evaluation of Irbene RT-16 Radio Telescope Receiving System

2017 ◽  
Vol 54 (6) ◽  
pp. 42-53 ◽  
Author(s):  
M. Bleiders ◽  
Vl. Bezrukovs ◽  
A. Orbidans
Keyword(s):  
Performance Evaluation ◽  
Flux Density ◽  
Radio Telescope ◽  
Total Power ◽  
Recent Measurement ◽  
Future Performance ◽  
Cassegrain Antenna ◽  
Vlbi Observations ◽  
Measurement Results ◽  
Beam Patterns

Abstract In the present paper, recent measurement results of refurbished Irbene RT-16 radio telescope receiving system performance are presented. The aim of the research is to evaluate characteristics of RT-16, which will allow carrying out necessary amplitude calibration in both single dish and VLBI observations, to improve the performance of existing system as well as to monitor, control and compare performance if possible changes in the receiving system will occur in future. The evaluated receiving system is 16 m Cassegrain antenna equipped with a cryogenic receiver with frequency range from 4.5 to 8.8 GHz, which is divided into four sub-bands. Multiple calibration sessions have been carried out by observing stable astronomical sources with known flux density by using in-house made total power registration backend. First, pointing offset calibration has been carried out and pointing model coefficients calculated and applied. Then, amplitude calibration, namely antenna sensitivity, calibration diode equivalent flux density and gain curve measurements have been carried out by observing calibration sources at different antenna elevations at each of the receiver sub-bands. Beam patterns have also been evaluated at different frequency bands. As a whole, acquired data will serve as a reference point for comparison in future performance evaluation of RT-16.

scholarly journals First Scientific VLBI Observations Using New Zealand 30 Meter Radio Telescope WARK30M

2015 ◽  
Vol 127 (952) ◽  
pp. 516-522 ◽  
Author(s):  
L. Petrov ◽  
T. Natusch ◽  
S. Weston ◽  
J. McCallum ◽  
S. Ellingsen ◽  
...  
Keyword(s):  
New Zealand ◽  
Radio Telescope ◽  
Vlbi Observations

scholarly journals A Tri-band Low-noise Cryogenic Receiver for Geodetic VLBI Observations with VGOS Radio Telescopes

2019 ◽  
Author(s):  
José A. López-Pérez ◽  
Félix Tercero-Martínez ◽  
José M. Serna-Puente ◽  
Beatriz Vaquero-Jiménez ◽  
María Patino-Esteban ◽  
...  
Keyword(s):  
Radio Telescope ◽  
Very Long Baseline Interferometry ◽  
Low Noise ◽  
Radio Telescopes ◽  
Geospatial Information ◽  
Ka Band ◽  
Geodetic Vlbi ◽  
Long Baseline ◽  
Vlbi Observations ◽  
X Band

This paper shows the development of a simultaneous tri-band (S: 2.2 - 2.7 GHz, X: 7.5 - 9 GHz and Ka: 28 - 33 GHz) low-noise cryogenic receiver for geodetic Very Long Baseline Interferometry (geo-VLBI) which has been developed by the technical staff of Yebes Observatory (IGN) laboratories in Spain. The receiver was installed in the first radio telescope of the Red Atlántica de Estaciones Geodinámicas y Espaciales (RAEGE) project, which is located in Yebes Observatory, in the frame of the VLBI Global Observing System (VGOS). After this, the receiver was borrowed by the Norwegian Mapping Autorithy (NMA) for the commissioning of two VGOS radiotelescopes in Svalbard (Norway). A second identical receiver was built for the Ishioka VGOS station of the Geospatial Information Authority (GSI) of Japan, and a third one for the second RAEGE VGOS station, located in Santa María (Açores Archipelago, Portugal). The average receiver noise temperatures are 21, 23 and 25 Kelvin and the measured antenna efficiencies are 70%, 75% and 60% in S-band, X-band and Ka-band, respectively.

scholarly journals 327 MHz Observations of 3C 84, 3C 120 and 1148-001

1988 ◽  
Vol 129 ◽  
pp. 121-122
Author(s):  
V. K. Kulkarni ◽  
S. Ananthakrishnan
Keyword(s):  
Radio Source ◽  
Radio Telescope ◽  
Seyfert Galaxies ◽  
Preliminary Results ◽  
Mixed Sample ◽  
Vlbi Observations ◽  
Nearby Galaxies ◽  
3C 120

We have made VLBI observations of a mixed sample of bright galaxies and quasars at 327 MHz using the Ooty Radio Telescope in India and the telescopes at Jodrell Bank, Westerbork, Torun, and Crimea in December 1983 and March 1986. MK II recording was used and the data were processed at MPI, Bonn. The preliminary results of the 1983 analysis (Ananthakrishnan and Kulkarni 1986) showed most of the nearby galaxies to be resolved over the longest baselines of 8 million wavelengths. The only seyfert galaxies for which good S/N ratio was available at the longest baselines were 3C84 and 3C120. Although UV coverage was poor we attempted to make maps of these objects. The radio source 1148-001 was used for gain calibration of the telescopes.

scholarly journals The Study of Scattering Effects by VLBI Observations of PSR 0329+54 with HALCA at 1650 MHZ

2001 ◽  
Vol 182 ◽  
pp. 39-42
Author(s):  
A.K. Yangalov ◽  
M.V. Popov ◽  
V.A. Soglasnov ◽  
K.V. Semenkov ◽  
H. Hirabayashi ◽  
...  
Keyword(s):  
Data Processing ◽  
Radio Telescope ◽  
Radio Interferometer ◽  
Space Radio Telescope ◽  
Vlbi Observations ◽  
Scattering Effects ◽  
Initial Results

AbstractPSR0329+54 was observed at 1.6 GHz with a space-ground radio interferometer with HALCA as a space radio telescope. The initial results of data processing are discussed.

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