Ultra-Rapid UT1 Measurement with VLBI (e-VLBI)

Ultra-Rapid UT1 measurement project has started since July 2007. Kashima 34m , Tsukuba 32m, Onsala 20m, Metsahovi 14m, and Wettzell 20m radio telescopes are participating the experiments. These stations has high speed network access with 1Gbps -- 10Gbps. The observed data are transfered to correlation station in real-time with those high speed network and processed. Estimation of UT1-UTC, which is one of the earth orientation parameter, can be output soon after the experiments.
The Mk3 database of the experiments are disclosed in the following links. The name of database files are following to the naming rule for this project.

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Date Experiment Code Stations 2007Apr03 U07093A Kashim34 Onsala60 2007Apr23 U07113 Kashim34 Onsala60 2007May02 U07122 Kashim34 Onsala60 2007May18 U07138 Kashim34 Metsahov 2007May30 U07150 Kashim34 Onsala60 2007May31 U07151 Kashim34 Onsala60 2007Jun04 U07155 Kashim34 Onsala60 2007Jul14 U07195 Kashim34 Onsala60 Tsukub32 Wettzell 2007Jul15 U07196 Kashim34 Onsala60 2007Sep04 U07247 Tsukub32 Onsala60 Metsahov V07247 Tsukub32 Onsala60 Metsahov W07247 Tsukub32 Onsala60 Metsahov 2007Oct25 W07247 Kashim34 Onsala60 2007Nov22 A07326 Tsukub32 Onsala60 B07326 Tsukub32 Onsala60 2007Nov26 U7330A Kashim34 Onsala60 U7330B U7330C U7330D U7330E U7330F 2007Dec14 U7348A Kashim34 Onsala60

Date Experiment Code Stations 2008Jan16 U8016A Kashim34 Metsahov 2008Jan17 U8017A Kashim34 Metsahov 2008Jan18 U8018A Kashim34 Metsahov U8018C 2008Feb21 U8052A Tsukub32 Onsala60 U8052B U8052C U8052D 2008Feb22 U8052B Kashim34 Onsala60 U8053C U8053D U8053E U8053F 2008Apr22 U8113A Kashim34 Onsala60 U8133B

• The list of all the databases is available at here
  
• Summary of the experiments is here

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Naming Rule of the Database File for Ultra-Rapid UT1 Experiment

The naming Rule of Mk3 Database Files of this Ultra-Rapid UT1 experiments is different from the definition of routine-basis VLBI experiments described in the master files . The definitions of the database naming rule for this Ultra-Rapid UT1 experiments is as follows:

• The format of name is "YYMMMDDXX_VDDD", where YY is last two digits of year, MMM is three-character abbreviation of the name of the month, DD is day of the month, XX is database code described below, DDD is version number.
• Database code XX is defined as follows:
  1. Database for X-band is indicated as '8*'.
  2. Database for S-band is indicated as '2*'.
  3. The data correlated at Kashima in realtime base is indicated as '*A'. If multiple real-time e-VLBI experiments were performed, '*K' , '*L' , '*M' ,... will be used. Because current UT1 experiment is not perfectly realtime, but setnding data in real time to Kashima. The data format conversion and correlation have been perfomred with the software correlator as the same with offline.
  4. The data correlated at Tsukuba in realtime base is indicated as '*B'.If multiple real-time e-VLBI experiments were performed, '*T' , '*U' , '*V' ,... will be used. Because current UT1 experiment is not perfectly realtime, but setnding data in real time to Kashima. The data format conversion and correlation have been perfomred with the software correlator as the same with offline.
  5. The data correlated at Kashima in offline base is indicated as '*K'. It is supposed to include all the available station's data. Offline/Realtime does not matter. If the experiments are repeated several times and data base is created with different name for each sessions, the following character may be used for DBC, such as '*L' , '*M', ...
  6. The data correlated at Tsukuba in offline base is indicated as '*T'. It is supposed to include all the available station's data. Offline/Realtime does not matter. If the experiments are repeated several times and data base is created with different name for each sessions, the following character may be used for DBC, such as '*U' , '*V', ...
  7. If the database contains the data which is duplicated with the other database in public, the database is indicated as '*Z'. Add-on experiment with Intensive-2 will be this case. The data is supposed to be processed at one correlation center. The information of the correlation center will not remain in the DBC in this case.
  8. As the same case with '*Z', but if that data is mixture of those processed at different correlation centers, it is indicate as '*Y'. This is not desirable to happen, though it is defined to distinguish from the other normal case.

Examples:

Session	Stations	DBC	Comments
U07JUL14	KbOn	8A,2A	Realtime
	TsWzOnKb	8Z,2Z	Add-on experiment with INT-2 session. All the data were reprocessed at Tsukuba.
U07SEP04	TsOnMh	8T,2T	All the data were processed at Tsukuba.
	TsOnMh	8U,2U	The second session
	TsOnMh	8V,2V	The third session