|
Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://www.vsop.isas.ac.jp/apt/meetings/APTfeb2002summary.html
Дата изменения: Wed Oct 23 11:22:15 2002 Дата индексирования: Tue Oct 2 04:18:00 2012 Кодировка: Поисковые слова: р р с п п п п п п п п п п п п п п р п р п п |
Agenda Summary -------------- 1. Welcome 2. APT Activities and Science Results 3. Observatory Reports 4. The future of the APT 1. Welcome ---------- APT co-chair Hisashi Hirabayashi (ISAS) welcomed participants to the meeting. APT Secretary Philip Edwards (ISAS) reviewed the aims of the APT (http://www.vsop.isas.ac.jp/apt/DefinitionAndAims.html). 2. APT Activities and Science Results ------------------------------------- Ed Fomalont (NRAO) described the participation of the APT in a 56 hour observing campaign of Sco X-1 in June 1999. The APT was used together with the Very Long Baseline Array (VLBA) and the European VLBI Network (EVN) to monitor this X-ray binary system at 5 GHz. The Australia Telescope Compact Array, and Ceduna, Hartebeesthoek, Kashima, Mopra, Parkes, and Shanghai telescopes of the Asia-Pacific Telescope participated in these observations. The observations were made using the phase referencing technique, with a calibrator 70 arcseconds from Sco X-1 (with the ATCA having to nod back and forth between the two). The results are described in two scientific papers, "Scorpius X-1: Energy Transfer from the Core to the Radio Lobes" by E.B. Fomalont, B.J. Geldzahler, and C.F. Bradshaw, in ApJ 553, L27 (2001), and "Scorpius X-1: The Evolution and Nature of the Twin Compact Radio Lobes" by E.B. Fomalont, B.J. Geldzahler, and C.F. Bradshaw, in ApJ 558, 283 (2001). NRAO has a press release describing the results, and with a link to a "movie" showing the evolution of the source over the 56 hours (see http://www.vsop.isas.ac.jp/apt/science.html). One of the main scientific activities of APT telescopes collectively has been participation in the VLBI Space Observatory Programme (VSOP). Philip Edwards gave a brief overview of the HALCA satellite and VSOP observing, and described a number of the scientific results of the mission. The participation of APT telescopes in the all-sky VSOP Survey Program was of particularly importance to the mission. In the absence of Tetsuo Sasao, Philip Edwards briefly described results of the APT 22 GHz observations conducted from October 1st to 5th, 1997. A written report is available in the Proceedings of the GEMSTONE meeting, January 1999 (CRL) p.142-146. The observations revealed both the strengths and weaknesses of the APT. The advantages included the high north-south resolution, the ability to correlate observations made in different recording formats, and the potentially high sensitivity at 22 GHz. The disadvantages were the unstable observing systems at some telescopes at that epoch (such as problems with PLOs and masers), the poor calibration information for some telescopes, and the insufficient east-west extent of the array. 3. Observatory Reports ---------------------- Observatory reports were presented for ATNF, Hobart & Ceduna by Tasso Tzioumis (ATNF), Kashima by Yasuhiro Koyama (CRL), NAO, including Nobeyama and VERA, by Makoto Inoue (NAO), Taeduk and the planned KVN by Young Chol Minh (TRAO), and Usuda by Kenta Fujisawa (NAO) Written reports were submitted for O'Higgins by Wolfgang Schlueter, the GMRT by Ananthakrishnan, SEST by Roy Booth, Itapetinga and Fortaleza by Pierre Kaufmann, and Russian telescopes by Igor Molotov and Hobart and Ceduna by Peter McCulloch. There are available from the APT web site. 4. The future of the APT ------------------------ "Hirax" Hirabayashi described the status of planning for the VSOP-2 project and the possibilities for APT involvement in the mission. The VSOP-2 satellite will most likely have observing bands at 5 or 8 GHz, 22 GHz and 43 GHz, and be launched toward the end of the decade. Philip Edwards outlined a number of items requiring action, including updating the APT web site (the results can be seen at http://www.vsop.isas.ac.jp/apt/) and the technical details of the individual APT telescopes. It was planned to hold the next APT meeting at the New Techniques in VLBI meeting in Korea in November 2002, with the following meeting to be held to coincide with the IAU General Assembly in Sydney in July, 2003.