Correlator Response Form Joint CSTG/IERS Call for Participation International VLBI Service for Geodesy and Astrometry Correlator name: Washington Correlator (WACO) Parent/Funding organization: National Earth Orientation Service (NEOS), a joint effort of U.S.Naval Observatory (USNO) and National Aeronautics and Space Administration (NASA) Name and title of primary technical contact: Dr. Kerry A. Kingham - Correlator Project Scientist kak@cygx3.usno.navy.mil Name and title of administrative contact: James O. Martin - Correlator Project Manager jom@cygx3.usno.navy.mil Mailing address: U.S. Naval Observatory EO Department 3450 Massachusetts Ave. NW Washington DC 20392-5420 (use 20008 for Fed Ex) Phone: 202-762-1464, 1565,1567,1492 Fax: 202-762-1563 E-mail address: waco@cygx3.usno.navy.mil Web address: http://maia.usno.navy.mil/eo/waco_intro.html List the networks/programs for which you correlate data: NEOS-A, CORE-A, CRF, SURVEY, NAVEX, occasional CORE-B and ad hoc southern reference frame sessions. Indicate correlator capacity: Number of baselines: 10 Number of stations: 6 Also possible: 2 independent correlators with 7 and 3 baselines, respectively. Number of playback units: 6 (4 Mk4, 2 Mk3A) Hours of operation per week: 80 regular + 32 overtime Number of full-time-equivalent personnel assigned to correlator functions: USNO staff: 2 CONTRACTOR staff: 8 Percentage of time correlator is used for geodesy/astrometry: 100% Percentage of total correlator capacity that is unused: 56/168 = 33.3% (i.e. correlator is idle 56 hrs per week) Internet connection type or bit rate: T1 Data storage capacity: 12 Gb online plus unlimited DAT archives Data Center(s) you use: CDDIS (Goddard), VLBA (Socorro), Bologna Describe any planned facility upgrades. The Mk3A correlator will be replaced by the Mk4 correlator - May 1999 The 2 remaining Mk3A playbacks will be upgraded to Mk4 2 additional Mk4 playbacks may be acquired in the future. Indicate which of the following IVS Correlator functions you perform and explain briefly how you will provide them: Receive, process, and archive VLBI data VLBI data tapes are received by mail and express services. Some tapes are picked up at airports and cleared through customs by USNO/Contractor personnel. Tapes are logged into the tape database and filed in tape storage cabinets. Correlator processing files are prepared from .skd files and .log files that have been placed on the data center computer. e-mail messages are used to add clocks and eliminate bad scans. The sessions are processed according to priority: NEOS-A and daily intensives are processed first in order to meet daily and weekly IERS Bulletin A deadlines. The most recently observed CORE-A is processed next. Processing consists of correlation on the Mk3A correlator and fringe fitting by fourfit on an HP9000 (cygx3). Processing is evaluated using HOPS. Re-processing is scheduled for poorly correlated or missing scans. When correlation is deemed reasonably complete an export is written to a tar file and a DAT and the analysis center is notified. Each session is archived some time later when a DAT tape and a copy are made (using tar) of the entire session. Shortly after a session is exported and the analysis center indicates they are satisfied, the VLBI data tapes are degaussed and sent to observing stations by mail, express service, and military transport. Provide timely feedback to stations Sessions are prepassed as soon as all tapes arrive. A prepass message is sent by e-mail indicating any obvious problems. The prepass may also be used to investigate suspected problems. During processing if problems are seen that will impact upcoming sessions stations are notified immediately. When an export is made, a final report is e-mailed and posted on cddisa. The final report summarizes processing statistics, snr achievements, and notes problems that were seen at each station. WACO always tries to respond to requests from stations, within the constraints of priority processing, to evaluate and diagnose problems. Maintain community tape pool Tapes are logged into the tape database when received and logged out when sent out. All tapes are entered into TRACK when received or sent out. Tapes are inspected when received and during processing for bad packing, damage, or poor slices and repaired if possible. Tapes are degaussed and inspected before being sent out. Tape shipping is coordinated with the other correlators. Make data available to the Analysis Centers Exports are written to DAT as well as a tar file that is available for electronic transfer. At the request of an Analysis Center, a database can be created and made available for transfer. Outside users who are familiar with HOPS can request access that will permit them to examine data in detail. Compare processing techniques, models, and outputs Techniques, software, and expertise are freely shared among all three Mk3A correlators. WACO correlator software and post processing software (HOPS) is almost entirely standard. Attach a list of personnel (names and titles) whom you designate as IVS Associate Members through their affiliation with your correlator: James O. Martin, Correlator Project Manager jom@cygx3.usno.navy.mil Dr. Kerry A. Kingham, Correlator Project Scientist kak@cygx3.usno.navy.mil Bruce Thornton, Correlator Contractor Manager blt@casa.usno.navy.mil Please provide any other information that you feel will be helpful in demonstrating your correlator's capabilities to participate in the IVS. If you proposed to the IERS in 1995/6 as a correlator facility and wish to have that proposal carry over to the IVS, please make such a statement in this proposal. WACO has operated for more than 10 years at loading factors close to and often exceeding 100% (using the split system) processing geodetic VLBIi, especially the timely processing of NEOS sessions to provide EOP. As time allows we have also processed a variety of special experiments such as phase-reference experiments, and observations of masers, supernovae, and gamma-ray bursters and other sources of astrophysical interest. We wish to have the NEOS proposal to the IERS for WACO as a correlator facility carry over to IVS. Your signature on this form indicates your agreement to participate in the IVS as a Correlator and to cooperate with the IVS Coordinating Center and with the IVS Coordinators. If this is a new proposal (i.e. not carried over from IERS) your signature commits your organization to participate in the IVS. Name of person signing: Dennis D. McCarthy, Director of Time, U.S Naval Observatory dmc@maia.usno.navy.mil Signature: _________________________________________ Date: _________________