Re: VLA - you might also be interested the HSA - High Sensitivity Array https://science.nrao.edu/facilities/vlba/HSA https://science.nrao.edu/facilities/vlba/HS

Re: VLA - you might also be interested the HSA - High Sensitivity Array https://science.nrao.edu/facilities/vlba/HSA https://science.nrao.edu/facilities/vlba/HSA In this, they take the VLA and add a few more big ones. > By adding the GBT, phased VLA, and/or Effelsberg to a VLBA experiment the sensitivity can be increased by an order of magnitude. This capability opens up new avenues for scientific discovery. The aim of the High Sensitivity Array initiative is to facilitate the planning, scheduling, and calibration of observations making use of this array. There's also The Impact of Arecibo's Sensitivity on VLBA Observations https://ui.adsabs.harvard.edu/abs/2005AAS...207.2907D/abstract https://ui.adsabs.harvard.edu/abs/2005AAS...207.2907D/abstra... > A growing number of observers are using large single-dish telescopes as elements in VLBI arrays for increased sensitivity. Recently, the High Sensitivity Array (HSA) has been formed by adding the phased Very Large Array, the Green Bank Telescope, the Effelsberg Telescope, and the 305m Arecibo Radio Telescope, to the Very Long Baseline Array (VLBA), to deliver very sensitive VLBI observations. Arecibo is the element that contributes most to the sensitivity of the HSA, but it has limited sky coverage. The study reported here has used the 305m Arecibo Radio Telescope with the VLBA to observe the compact radio source J0837+2454, and carry out a systematic analysis of the impact of including Arecibo. In these observations, Arecibo participated for about 25% of the total observing time. ...