16th IVS Directing Board meeting Summary notes Held at Haystack Observatory, Westford, MA, U.S.A. September 16, 2006 Notes by DB, first version 061010 revised 061027, 061103 Attending: Wolfgang Schlueter, Arthur Niell, Chopo Ma, Dirk Behrend, Ed Himwich, Kerry Kingham, Yasuhiro Koyama, Bill Petrachenko, Harald Schuh, Axel Nothnagel, Zinovy Malkin, Patrick Charlot, Franco Mantovani, Alan Whitney ACTIONS: 1. Welcome (Wolfgang Schlueter) Shigeru Matsuzaka and Roy Booth could not attend. Patrick Charlot is the new IAU representative on the board replacing Patrick Wallace. 2. Reports and discussion 2.1 Chair's report (Wolfgang Schlueter) Activities since the last board meeting were reported. Meetings: - GGOS Retreat in Munich, Germany in February; Wolfgang and Dirk prepared a note about IVS contributions to GGOS and expectations from GGOS. - EVN meeting in Firence, Italy in May; Wolfgang gave a report about VLBI2010 and the work of the VLBI2010 Committee. - VLBI2012 meeting in St. Petersburg, Russia in September; Wolfgang gave a report about IVS. Publications: - For the special issue "VLBI" of the Journal of Geodesy the paper "The IVS and Its Fundamental Role in Related Science and Applications" has been prepared and is currently being revised. - Preparation of a 6 page abstract "IVS and VLBI2010" for the VLBI2012 meeting. Correspondence: - Letter to John LaBrecque (NASA HQ) expressing the IVS' concern with regard to suspending operations at Gilmore Creek. - Letter to John Dickey (Univ Tasmania) supporting the efforts to get funds for the operation of Hobart after the reorganisation of Geoscience Australia. - Letter to Andrey Finkelstein (IAA RAS) accepting IAA's proposal to host the 2008 General Meeting in St. Petersburg. - Letter to K. Elango (Indian Space Research Organization) supporting the efforts to include the 32m-telescope being built for India's lunar mission near Bangalore, India in international VLBI and IVS activities. - Letter to Kazuo Shibuya (NIPR, Japan) giving support for continued VLBI operations at Japan's Antarctic station Syowa. - Letter to the Station Managers of the IVS Network Stations informing about the need of met data and requesting input on necessary metadata. - Letter to Alexandre Vassiliev (International Telecommuniation Union) outlining the IVS experience with the last leap second event. - Letter to Alexander Stepanov (Pulkovo Observatory) welcoming Pulkovo as an Associate Analysis Center of IVS. 2.2 Coordinating Center report (Dirk Behrend) Activities since the last board meeting were: - Publication of April and August Newsletters, 2005 Annual Report, and 2006 General Meeting Proceedings. - Maintenance of mailing lists and web site. - CONT05 refringing support. - VLBI2010 Committee (V2C) support. - Liaison with other services in the frame of the INDIGO and GGOS projects. - Commenced update of Associate Member list. The August Newsletter contained request for update. Dirk will follow up with individual requests to the contact persons of the permanent components. The terms for the two Networks representatives (Wolfgang Schlueter and Shigeru Matsuzaka) and the term for the Correlators and Operation Centers representative (Kerry Kingham) expire in February 2007. Alan Whitney, Harald Schuh, and Dirk Behrend agreed to serve as the Election Committee. Wolfgang appointed Alan to be the chair. The terms of the three At Large members also expire in February 2007. All three positions will be elected by the board, after the election of the representative positions is complete, with the purpose of balancing the board. The nomination phases for the representatives and the At Large members will be done in two separate stages. An individual can only serve two consecutive full terms on the Board in any of the representative and at large positions. Partial terms are not counted to this limit. Activities for the next several months include: - Completion and publication of the VLBI color brochure. - Continued participation in INDIGO and GGOS projects. - Upgrading the IVS web site to include station pages. - Publication of December and April Newsletters. - Publication of 2006 Annual Report. - Coordination of the IVS elections. - Coordination of Technical Operations Workshop (TOW2007). - Coordination of the 5th IVS General Meeting (GM2008). 2.3 Observing Program Committee report (Dirk Behrend) Issues discussed in the period since the last board meeting were: - Fortaleza VC upgrade. - T2 priority. - RFI impact. - Tape drive retirement. - R&D proposal for testing Intensive scheduling. - CONT08. Another continuous VLBI campaign is planned for 2008. Goals and time frame still to be determined. - 2007 observing program. The observing plan for 2007 is similar to previous years. The Board agreed that the OPC be extended with a member from IAA. 2.4 Analysis Coordinator report (Axel Nothnagel) A second EOP series referenced to the middle of the session is being produced in addition to the one referenced to midnight. The mirroring scheme of the data centers was densified. ITRF2005. A scale issue between VLBI and SLR surfaced in the ITRF2005 validation. The VLBI scale fits well to the ITRF2000 scale. From Jan 1, 2007 onward, EOP series will be created from SINEX combinations only. Cable cal readings appear to be critical in solutions: turning off cable cal furnishes different results. It is inconclusive at this point which version yields more realistic results. The Board accepted Axel's proposal to turn the Pilot Project (PP) "Baseline Lengths" into an operational product. The PP was closed. 2.5 Network Coordinator report (Ed Himwich) Station issues: - Algonquin (antenna drive problems) - Seshan (rail problem) - TIGO (formatter failure) - Simeiz (Mark 5 unavailable) - Zelenchukskaya (one BBC failed) - Badary: needs Mark 5B upgrade (and possibly sampler) and one BBC Clock offets: - Mark IV correlators using consistent offsets at 100 ns level - GSI correlator appears to be off by about 1 us, but this only affects weekend Intensives - S2 correlator offset is not known - Kokee is reference for historical reasons (needs to be calibrated) Clock rates: - desired specifications is 3E-13 to 6E-13 - current performance consistency: 6E-13 for Mark IV correlators and 1E-11 for GSI K5; S2 is unexamined - accuracy is unknown (plan to measure relative to GPS) 2.6 Technology Coordinator report (Alan Whitney) VSI-E: Beta version of VSI-E is being tested in transfers from Kashima to Haystack. Progress towards routine e-VLBI: Data are now transmitted routinely from Ny Alesund with a data rate of about 80 Mbps. In August 2006 MPI Bonn was connected at 1 Gbps. Mark 5B status: Checkout of Mark 5B is complete. Successful correlation and fringes from Mark 5B data. 20 Mark 5B I/O boards have been built and tested. Design has been transferred to Conduant Corp and is available to order (~$3K to upgrade from Mark 5A; ~$20K for new Mark 5B system). Mark 5B+: Expansion of Mark 5B to 2 Gbps now working. Requires upgraded StreamStor disk interface card. The upgrade from Mark 5A to Mark 5B+ costs around $13K. Mark 5B Interface Boards: VSI-4 sampler adapter board will be placed inside Mark IV formatter to upgrade to VSI. Haystack accepts orders for upgrade kits for a limited time (till 30 Sep 2006, but to be extended). VSI-C sampler adapter interfaces VLBA samplers to VSI, was designed at Metsahovi. Mark 5A/B Compatibility: Mark 5B can play only Mark 5B recordings (VSI format in/out). Upgraded Mark 5A ("Mark 5A+") will be able to play all Mark 5A recordings and Mark 5B recordings that are made in selected modes. 2.6.1 Report from NICT (Yasuhiro Koyama) Developments of K5/VSSP32 system: - Supports 1024 Mbps observation mode - 4 systems have been deployed (1 at Tsukuba and 3 at Kashima) - currently causes spontaneous data error (once every ~150 seconds); need to develop a way to flag bad data in the K5 to Mark 5 file format conversion New geodetic VLBI station plan in Korea: - NGII funded to develop new geodetic VLBI station in Suwon - Kondo-san is member of advisory board for the project - GSI (Tsukuba) and NICT (Kashima) will cooperate with NGII to develop the new station 2.6.2 IVS Representation in CRAF (Wolfgang Schlueter) Franco will talk to Prof. Ambrosini (Chair of CRAF) with regards to an IVS representation. 2.7 VLBI2010 Committee report (Bill Petrachenko) The WG3 proposed 13 study areas in its final report. The V2C is carrying forward the recommendations of WG3. The committee meets in monthly telecons. It had a face-to-face meeting in Concepcion, Chile and hold the First VLBI2010 Working Meeting at Haystack. [The next Working Meeting is planned to take place on April 15, 2007 in Vienna, Austria.] The primary goal is to come up with specifications for the VLBI201o antenna. A highlight of the work so far was the development of Monte Carlo simulators. Simulations showed that the troposphere is the major accuracy-limiting effect. Clocks are less important. The V2C agreed to set the specifications for the VLBI210 antenna at 12-m dish size (minimum) and 30-sec end-to-end slew time. The frequency range shall be 2-18 GHz. The slew time and frequency range are strawman values. 3. Items related to IAG, IAU, EVN 3.1 IAG 3.1.1 IAG (Harald Schuh) There are three representatives of the measurement services on the IAG Executive Committee. New elections will be held at the next General Assembly in Perugia in 2007. Harald agrees to be a candidate for IVS. 3.1.2 GGOS (Dirk Behrend and Chopo Ma) The GGOS Steering Committee met at a retreat in Munich and during the EGU meeting in Vienna. An Executive Committee was established consisting of the three GGOS chairs and three at large members. Chopo Ma, Mike Pearlman, and Susanna Zerbini are the at large members. Interim Terms of Reference (ToR) were formulated and approved; they are valid until the IAG General Assembly in Perugia 2007. By the Perugia meeting the final ToR will be set up in order to be approved. A Science Panel was established that began work on a strategic plan (science plan) for GGOS. 3.1.3 IERS (Chopo Ma) The IERS focussed on the ITRF2005 determination and validation. Unexpected difficulties surfaced with scale differences between VLBI and SLR that are still being discussed. 3.1.4 EVGA (Axel Nothnagel) The next European VLBI meeting will be on April 12 and 13. The IVS Analysis Workshop will take place on April 13 and 14. These meetings precede the EGU 2007 General Assembly. The first circular will be sent out soon. 3.2 IAU (Patrick Charlot) The XXVIth IAU General Assembly was held in Prague on August 14-25, 2006. The Division I (Fundamental Astronomy) Meeting featured reports from the Working Groups "Precession and the Ecliptic" (proposing 1 resolution), "Nomenclature for Fundamental Astronomy" (proposing 2 resolutions), "Definition of Coordinated Universal Time", " Future Developments of Ground-Based Astrometry", and "Relativity in Celestial Mechanics, Astrometry and Metrology". The following IAU Resolutions passed: - IAU 2006 Resolution 1: Adoption of the P03 Precession Theory and the Definition of the Ecliptic - IAU 2006 Resolution 2: Supplement to the IAU 2000 Resolutions on Reference Systems (harmonizing the name of pole and origin to "intermediate", default orientation of the Barycentric Celestial Reference System and Geocentric Celestial Reference System) - IAU 2006 Resolution 3: Redefinition of the Barycentric Dynamical Time (TDB) (complete text of IAU Resolutions available at http://syrte.obspm.fr) Commission 19 (Earth Rotation) Meeting had reports on: IERS, IVS, FAGS, SOFA, IERS Conventions. The scientific session featured talks on: - Reference Frames and their links with other astronomical frames and their densification - Observation and theory of polar motion and length-of-day - Observation and theory of precession and nutation - Present Earth orientation parameter determination Commission 8 (Astrometry) Meeting scientific session "Frontiers of Astrometry": - mostly optical space-astrometry missions (GAIA, SIM, JASMINE) - one invited presentation on radio-astrometry: "Synergy between radio astronomy and astrometry" by Ed Fomalont - Advertisement for IAU Symposium No. 248: "A Giant Step: from Milli- to Microarcsecond Astrometry", October 15-19, 2007, Shanghai JD16: "Nomenclature, Precession and New Models in Fundamental Astronomy" was held on August 22-23, 2006 and was organized by N. Capitaine & J. Vondrak. The scientific program had 6 sessions (State of the art of the implementation of the IAU resolutions, Precession and the ecliptic, The high accuracy models for reducing astronomical data, New terminology in fundamental astronomy, Scientific applications of high accuracy astronomy, and General discussion). Division I officers (2006-2009): - President: J. Vondrak - Vice-President: D.D. McCarthy - Commission 1 (Relativity): S. Klioner and G. Petit - Commission 4 (Ephemerides): T. Fukushima and G.H. Kaplan - Commission 7 (Cel. Mechanics): J. Burns and Z. Knezevic - Commission 8 (Astrometry): I. Kumkova and D.W. Evans - Commission 19 (Earth rotation): A. Brzezinski and C. Ma - Commission 31 (Time): P. Defraigne and R. Manchester Division I Working Groups (2006-2009): - Future Development of Ground-based Astrometry (Chair: W. Thuillot) - Second Realization of the ICRF (Chair: C. Ma) - Numerical Standard of Fundamental Astronomy (Chair: B. Luzum) Inter-Division I/III Working Group: - Natural Satellites (Chair: J.E. Arlot) 3.2.1 IAU WG to oversee next ICRF (Chopo Ma) The initial idea to have a technical WG was changed to make it an oversight WG over the effort. Chopo proposed to establish a joint IVS/IERS Working Group with the goal to present the next realization of the ICRF at the next IAU General Assembly in 2009. 3.3 FAGS (Dirk Behrend) A FAGS General Committee meeting took place at Paris Observatory on March 29, 2006. ICSU extended the sponsorship for 3 years. In September 2006 a new evalution ad-hoc group will be assembled at ICSU; its first meeting is anticipated for early 2007. Renaming FAGS to CAGS is off the table: FAGS is a long established name that should not be changed. Nicole Capitaine is new chair of FAGS. 3.4 EVN (Franco Mantovani) The EVN started to observe disk-only. No more tape drives will be used. EVN plans to adopt the NorthStar system as proposal tool. There are three aspiring stations: Evpatoria (70-m dish, Crimea, Ukraine), Irbene (32-m dish, Latvia), and Simeiz (22-m dish, Ukraine). The next TOG meeting will be held at Noto Observatory in December. A European Interometry School is planned for next year to be hosted by MPIfR in Bonn. 4. Technical discussions 4.1 Met data for the VLBI analysis (Wolfgang Schlueter) The response to Wolfgang's letter to the station managers requesting met data was meager. It appears that not all stations are aware of the fact that the quality of the results depends on the quality of the met data. 4.2 JoG special issue VLBI (Harald Schuh) The response to the call was very positive. The number of submitted papers might open the possibility of publishing a double issue. 5. Meetings The 2008 General Meeting will be held in St. Petersburg, Russia. It is to be scheduled in the first half of March. Details will be determined in discussions between the LOC and the Coordinating Center. The first circular will be sent out by March/April 2007. Next IVS board meeting at Wettzell on February 16, 2007. [In an email discussion after the board meeting, the date was changed to February 24, 2007.]