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Jim Lovell - 26 May 2016
Kashima 34m
Focal position adjustment of 2.4m dish and pointing observation was repeated. A experiment with GALA-V system (Kas34-Mbl1-Mbl2) was made on 26-27 May.
Boradband (5.9GHz,7.1Ghz,8.7GHz,10.6GHz) VLBI experiments on GALA-V network (Kas34-MBL1-MBL2) were repeated several times(May26, Jun24, Jul10). It s purpose is evaluation of broadband VLBI precision. Observed data were correlated by GICO3 software correlator and stored in Mk3DB. Then solution with CALC11/Solve indicating that even with small diameter antenna (SEFD~5.e5Jy vs SEFD~2000 Jy pairs), we can get geodetic solution with ~30 ps delay residual. It is promising that VGOS (2000Jy - 2000Jy) observation should get high delay precision measurement. We are planning to make further test experiments with Ishioka-MBL1-MBL2 in August. A long baseline observation test was made between Yebes-Kashima34 in June. but because of observation modes were different at each site (Broad channel at Kashima and narrow channel at Yebes), correlation process is required some modification. Another test experiment has been discussed between Takefuji and Jim.
Mamoru Sekido - 27 July Mamoru Sekido - 26 May 2016
Yebes
Broadband system temperatures are ~ 50 K - 70 K. The warm amplifiers after the cryogenic ones and before the optical fiber converters had to be removed to avoid saturating the amplifiers used to modulate the optical laser. This increased the Tsys by a factor 2. Furthermore one of the optical channels uses an 18 dB amplifier and the other one 9 dB. This is an issue to be solved in the future.
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