Imaging Simulations for the Korean VLBI Network (KVN)
The Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three 21m radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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The Korean Space Science Society
2005-03-01
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| Series: | Journal of Astronomy and Space Sciences |
| Subjects: | |
| Online Access: | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2005/v22n1/OJOOBS_2005_v22n1_1.pdf |
| _version_ | 1797369804377554944 |
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| author | Tae-Hyun Jung Myung-Hyun Rhee Duk-Gyoo Roh Hyun-Goo Kim Bong-Won Sohn |
| author_facet | Tae-Hyun Jung Myung-Hyun Rhee Duk-Gyoo Roh Hyun-Goo Kim Bong-Won Sohn |
| author_sort | Tae-Hyun Jung |
| collection | DOAJ |
| description | The Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three 21m radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the antenna configuration, source size, declination and the shape of target. In this paper, imaging simulations are carried out with the KVN system configuration. Five test images were used which were a point source, multi-point sources, a uniform sphere with two different sizes compared to the synthesis beam of the KVN and a Very Large Array (VLA) image of Cygnus A. The declination for the full time simulation was set as +60 degrees and the observation time range was --6 to +6 hours around transit. Simulations have been done at 22GHz, one of the KVN observation frequency. All these simulations and data reductions have been run with the Astronomical Image Processing System (AIPS) software package. As the KVN array has a resolution of about 6 mas (milli arcsecond) at 22GHz, in case of model source being approximately the beam size or smaller, the ratio of peak intensity over RMS shows about 10000:1 and 5000:1. The other case in which model source is larger than the beam size, this ratio shows very low range of about 115:1 and 34:1. This is due to the lack of short baselines and the small number of antenna. We compare the coordinates of the model images with those of the cleaned images. The result shows mostly perfect correspondence except in the case of the 12mas uniform sphere. Therefore, the main astronomical targets for the KVN will be the compact sources and the KVN will have an excellent performance in the astrometry for these sources. |
| first_indexed | 2024-03-08T17:52:12Z |
| format | Article |
| id | doaj.art-70d90f3ef7ae4c32b7424bdc4be292c0 |
| institution | Directory Open Access Journal |
| issn | 2093-5587 2093-1409 |
| language | English |
| last_indexed | 2024-03-08T17:52:12Z |
| publishDate | 2005-03-01 |
| publisher | The Korean Space Science Society |
| record_format | Article |
| series | Journal of Astronomy and Space Sciences |
| spelling | doaj.art-70d90f3ef7ae4c32b7424bdc4be292c02024-01-02T07:01:28ZengThe Korean Space Science SocietyJournal of Astronomy and Space Sciences2093-55872093-14092005-03-0122111210.5140/JASS.2005.22.1.001Imaging Simulations for the Korean VLBI Network (KVN)Tae-Hyun Jung0Myung-Hyun Rhee1Duk-Gyoo Roh2Hyun-Goo Kim3Bong-Won Sohn4Korea Astronomy Observatory, Daejeon 305-348, KoreaYonsei University Observatory, Yonsei University, Seoul 120-749, KoreaKorea Astronomy Observatory, Daejeon 305-348, KoreaKorea Astronomy Observatory, Daejeon 305-348, KoreaKorea Astronomy Observatory, Daejeon 305-348, KoreaThe Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three 21m radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the antenna configuration, source size, declination and the shape of target. In this paper, imaging simulations are carried out with the KVN system configuration. Five test images were used which were a point source, multi-point sources, a uniform sphere with two different sizes compared to the synthesis beam of the KVN and a Very Large Array (VLA) image of Cygnus A. The declination for the full time simulation was set as +60 degrees and the observation time range was --6 to +6 hours around transit. Simulations have been done at 22GHz, one of the KVN observation frequency. All these simulations and data reductions have been run with the Astronomical Image Processing System (AIPS) software package. As the KVN array has a resolution of about 6 mas (milli arcsecond) at 22GHz, in case of model source being approximately the beam size or smaller, the ratio of peak intensity over RMS shows about 10000:1 and 5000:1. The other case in which model source is larger than the beam size, this ratio shows very low range of about 115:1 and 34:1. This is due to the lack of short baselines and the small number of antenna. We compare the coordinates of the model images with those of the cleaned images. The result shows mostly perfect correspondence except in the case of the 12mas uniform sphere. Therefore, the main astronomical targets for the KVN will be the compact sources and the KVN will have an excellent performance in the astrometry for these sources.http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2005/v22n1/OJOOBS_2005_v22n1_1.pdfKorean VLBI Networkradio interferometryimaging simulation |
| spellingShingle | Tae-Hyun Jung Myung-Hyun Rhee Duk-Gyoo Roh Hyun-Goo Kim Bong-Won Sohn Imaging Simulations for the Korean VLBI Network (KVN) Journal of Astronomy and Space Sciences Korean VLBI Network radio interferometry imaging simulation |
| title | Imaging Simulations for the Korean VLBI Network (KVN) |
| title_full | Imaging Simulations for the Korean VLBI Network (KVN) |
| title_fullStr | Imaging Simulations for the Korean VLBI Network (KVN) |
| title_full_unstemmed | Imaging Simulations for the Korean VLBI Network (KVN) |
| title_short | Imaging Simulations for the Korean VLBI Network (KVN) |
| title_sort | imaging simulations for the korean vlbi network kvn |
| topic | Korean VLBI Network radio interferometry imaging simulation |
| url | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2005/v22n1/OJOOBS_2005_v22n1_1.pdf |
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