Biennial Report 2005-2006

Biennial Report 2005-2006

European Consortium for VLBI Biennial Report 2005-2006 1 Table of Contents Foreword by the Chairman of the Consortium...........................................3 1. The European Consortium for VLBI..........................................................5 2. Reports on Scientific VLBI related research..............................................6 3. EVN Network Operations.........................................................................35 4. Joint Institute for VLBI in Europe............................................................43 5. VLBI Operations support at member Institutes........................................64 6. VLBI Technical Activities at member Institutes......................................79 7. EVN Publications including external PIs – 2005 - 2006..........................99 2 Foreword by the Chairman of the Consortium The European VLBI Network (EVN) is an interferometric array of radio telescopes which allows high-resolution radio astronomical observations of cosmic radio sources to the whole astronomical community world-wide. The EVN is the most sensitive VLBI array in the world, thanks to the collection of extremely large telescopes that contribute to the network. Besides, new telescopes are coming on line. The Observatorio Astronómico Nacional in Spain and the Istituto di Radioastronomia of the Istituto Nazionale di Astrofisica in Italy, are completing new impressive observing facilities. The 40-m dish in Yebes (Spain) and the 64- m Sardinia Radio Telescope in Italy will greatly increase the sensitivity of the array and will make the EVN more attractive for observations at millimetre wavelengths. Moreover, there are other stations in Latvia with the 30-m dish at Irbene, and in Ukraine with the 70-m dish in Evpatoria and the 22-m dish in Simeis which are willing to join the EVN for future observations. This expansion of the EVN to the East is also important to fill the gap between the European observatories and the two Chinese antennas which are part of the network. The EVN regularly observes with the Associate Members at Arecibo Observatory (Puerto Rico), and Hartebeesthoek Radio Observatory in South Africa. EVN observations are regularly scheduled with the USA Very Long Baseline Array and with stations of NASA's Deep Space Network. The EVN has also operated jointly with the VLBI Space Observatory Programme (VSOP) and is working towards a collaboration with the VSOP-2 project (both space programs led by Japan). The relationship between the EVN and the International VLBI Service for Geodesy & Astrometry has improved during the time of this report. This Biennial Report covers the EVN activities for the period 2005-2006. Scientific, technical and operational activities of the member and associated institutes and the users are presented. Most of the report describes and highlights the impressive amount of science carried out with the EVN by its member institutes. The large number of publications on major astronomical journals and of contributions to many conferences based on EVN observations are listed at the end of the report. The scientific community is involved in the important document named EVN2015, which presents the future science to be conducted with the VLBI technique. Significant enhancements on the technical side have been achieved in the past two years. It is worth mentioning here that the EVN has completed the introduction of disk-based recording systems which greatly improved the reliability of the network. Stations have now enough disk space to sustain 10 days of observing at 1 Gbps. Enormous progress has also been made in the prototyping of Digital Base Band Converters (DBBC). That project was endorsed by the EVN after a positive report by the Critical Design Review Committee appointed by the Consortium Board of Directors. The DBBCs will be adopted in future as standard VLBI data acquisition systems by the network. A weak point in the network operations is represented by the difficulty of quickly changing the observing frequency. Despite of the agreement reached by the 3 member institutes to upgrade the antennas, only a few stations do currently perform with frequency agility. Nevertheless, the EVN is now able to plan for Target of Opportunity observations in case of rapid response required to the network by transient astronomical events. Huge progress has been made in electronic VLBI. Thanks to the EC funded programme EXPReS several EVN antennas are linked to the JIVE correlator with optical fibres. This moves towards real-time VLBI. On the one hand this means the death of the "traditional" VLBI, on the other it represents the future of EVN and again requires fully frequency agile stations. In the two years period covered by this report the EVN member institutes and partners successfully carried on "RadioNet", an Infrastructure Cooperation programme funded by the Sixth Framework Programme of the European Union. The RadioNet programme incorporates a Transnational Access programme aimed at improving the service to the EVN user community. Several Network Activities further strengthen the cooperation among the network partners. The EVN has demonstrated to be a vital, successful and attractive organization, an excellent example for a long-standing international collaboration between scientific partners at various institutes in and outside Europe. To this end, EVN is vitally dependent on national financial investments in support to radio astronomical observations and technical developments. Franco Mantovani, Istituto di Radioastronomia, Bologna Chairman, EVN Consortium Board of Directors Marco Bondi, Istituto di Radioastronomia, Bologna Secretary, EVN Consortium Board of Directors 4 1. The European Consortium for VLBI The European VLBI Network (EVN) was formed in 1980 by a consortium of five of the major radio astronomy institutes in Europe (the European Consortium for VLBI). Since then, the EVN and the Consortium has grown to include 12 institutes with 16 telescopes in Spain, UK, the Netherlands, Germany, Sweden, Italy, Finland, Poland and China, a 16 station data processor at JIVE in Dwingeloo and a 9 station data processor at MPIfR in Bonn. In addition, the Hartebeesthoek Radio Astronomy Observatory in S. Africa and the NAIC Arecibo Observatory in Puerto Rico are active Associate Members of the EVN. Together, these individual centres form a large scale facility, a continent-wide radio telescope. The EVN is linked on a regular basis to the 7-element Jodrell Bank MERLIN interferometer in the UK to create a very sensitive "regional network", and to the US NRAO Very Long Baseline Array and the NASA Deep Space Network to create a "Global Network". The EVN, in stand-alone or global mode, also observed together with the orbiting radio telescope HALCA launched in February 1997 by the Institute of Space and Astronautical Science (ISAS) in Japan as part of the first dedicated Space VLBI mission VSOP (VLBI Space Observatory Programme). Preliminary agreements between EVN and ISAS for the fore-coming VSOP-2 mission have been arranged. The member institutes of the Consortium are (in alphabetical order): Radio Astronomy 1) ASTRON, The Netherlands Foundation for Research in Astronomy, Dwingeloo, The Netherlands 2) Hartebeesthoek Radio Astronomy Observatory (HartRAO), S. Africa (Associate Member) 3) Institute of Radio Astronomy (INAF IRA), Bologna, Italy 4) Jodrell Bank Observatory (JBO), University of Manchester, Jodrell Bank, UK 5) Joint Institute for VLBI in Europe (JIVE), Dwingeloo, the Netherlands 6) Max-Planck-Institute for Radio Astronomy (MPIfR), Bonn, Germany 7) Metsähovi Radio Observatory (MRO), Helsinki University of Technology, Espoo, Finland 8) National Astronomical Observatory (OAN), Madrid, Spain 9) National Astronomy and Ionosphere Center, Arecibo Observatory, Puerto Rico (Associate Member) 10) Onsala Space Observatory (OSO), Chalmers University of Technology, Onsala, Sweden 11) Shanghai Astronomical Observatory, National Astronomical Observatories, Shanghai, P.R. China 12) Toruń Centre for Astronomy, Nicolaus Copernicus University, Toruń, Poland 13) Urumqi Astronomical Observatory, National Astronomical Observatories, Urumqi, P.R. China Geodesy 14) Bundesamt für Kartographie und Geodäsie (BKG), Wettzell, Germany The EVN Consortium Board of Directors (CBD) is a body whose membership consists of the Directors of the member institutes of the EVN. It meets twice a year to discuss EVN policy, operational, technical and strategic issues. The CBD elects a Chairman and vice- Chairman from its ranks who serve for a period of 2 years 5 2. Reports on Scientific VLBI-related Research The scientific research carried out by various groups using EVN facilities cover a wide range of topics, from the Solar System and nearby Universe to the very distant objects. Here we present a summary of some of these studies starting with those dealing with far away Active Galactic Nuclei (AGN) and then moving as close as our Solar System. 2.1. AGN phenomena on the parsec scale 2.1.1 BL lac Objects and Quasars A number of projects deal with the study of quasars and BL Lac objects. On the parsec scale all these objects show a compact core and a one-sided jet. In some cases, individual components in the jet can be tracked with multi- epoch observations to derive the kinematics of the relativistic flow. A set of 37 ultra-high-resolution GMVA and VLBA images of the quasar NRAO 150 have been analyzed by Agudo (MPI) and collaborators. This monitoring program, which spans about 10 years, shows a counter-clockwise

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    120 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us