Topic
Heliograph
About: Heliograph is a research topic. Over the lifetime, 65 publications have been published within this topic receiving 390 citations. The topic is also known as: heliography.
Papers published on a yearly basis
Papers
1 Mar 2006
TL;DR: In this article, the authors report results from an ongoing program of combining visibilities from the giant meterwave radio telescope (GMRT) and the Nancay Radio Heliograph (NRH) to produce composite snapshot images of the sun at meter wavelengths.
Abstract: We report first results from an ongoing program of combining visibilities from the giant meterwave radio telescope (GMRT) and the Nancay Radio Heliograph (NRH) to produce composite snapshot images of the sun at meter wavelengths. We describe the data processing, including a specific multi-scale clean algorithm. We present results of a) simulations for two models of the sun at 327 MHz, with differing complexity b) observations of a complex noise storm on the sun at 327 MHz on Aug. 27, 2002. Our results illustrate the capacity of this method to produce high dynamic range snapshot images when the solar corona has structures with scales ranging from the image resolution of 49" to the size of the whole sun.We emphasize that snapshot images of a complex object such as the sun, obtained by combining data from both instruments, are far better than images from either instrument alone, because their uv-coverages are very complementary.
31 citations
1 Jan 1958
TL;DR: The radio heliograph as mentioned in this paper combines principles of the multielement interferometer and the Mills Cross, and is used to produce pencil beams about 3? arc wide for the first time.
Abstract: A survey is given of the very highly directive equipment and methods which have been devised to obtain details of the distribution of radio emission over the solar disk. A new instrument is described; it operates on a wavelength of 21 cm and gives, for the first time, radio pictures of the sun. This radio heliograph combines principles of the multielement interferometer and the Mills Cross. It consists of 64 parabolic antennas, 19 feet in diameter, arranged along two lines, each 1240 feet in length, in form of a cross. Multiple pencil beams about 3? arc wide are produced by the system; by means of these, the sun is scanned television-wise. The radio heliograph is being used to produce daily pictures of the sun.
28 citations
TL;DR: In this article, the UTR-2 was used to locate two-dimensional positions of the solar decametric radio bursts using a rapid-scanning pencil-beam with an accuracy of 5 arc min.
Abstract: To locate two-dimensional positions of the solar decametric radio bursts a heliograph was developed on the basis of the UTR-2 radiotelescope (Khar'kov) operated in the range 10–26 MHz. The beamwidth of the heliograph rapid-scanning pencil-beam is 25 arc min at 25 MHz, and its field of view is about 3.5° (E-W) × 2.0° (N-S). The instrument yields rapidly forty records of the radio brightness of all (8 × 5) elementary parts (each 25 arc min in diameter) of the investigated sky area during every period of 1/4 s. Both coordinates of a burst center are measured with an accuracy 5 arc min. The bandwidth of the receiving system is 10 kHz. The heliograph operates in conjunction with a radiospectrograph connected to the output of a N-S arm of the UTR-2 array. The data observations with the UTR-2 correspond only to one linear polarized component.
23 citations
TL;DR: In this article, an expression for the coronal magnetic field strength from the observations of brightness, temperature, peak frequency, spectral index, and polarization degree of solar microwave bursts was derived for the first time.
17 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 2 |
| 2019 | 2 |
| 2018 | 2 |
| 2015 | 2 |
| 2014 | 2 |