The MEXART interplanetary scintillation array in Mexico

We report advances in the construction of a 64x64 (4096) full wavelength dipole antenna array, which will operate at 140 MHz, occupying 10 000 square meters (70 m x 140 m) to carry out interplanetary scintillation (IPS) observations. This will be a dedicated radio array of nearly 1000 well known radio sources which is being built in the state of Michoacán 350 km north-west from Mexico City, lat. 19°48’ N, long. 101°41’ W and 1964 m above sea level. The Mexican Array Radio Telescope (MEXART) will have similar characteristics to the MRAO array in Cambridge, but with significant advantages such as a better electronic system, higher operation frequency, state of the art back end, and location at intermediate geomagnetic latitudes (29°). The MEXART project consists of two phases. In the first phase, we built a prototype radio array near Mexico City, which contained all the basic antenna elements of the final array but covering a smaller area (1000 square meters) and operating with a 4x4 Butler matrix. In the second phase we are building the final array in Michoacán with technical assistance by NCRA-TIFR in India. MEXART will be the only IPS station in the American continent and will be part of a global network of IPS observatories combining measurements with ORT in India and the STEL IPS systems in Japan. Combining data from these IPS observatories will provide important information for solar wind studies and in particular for solar activity associated storms and ionospheric disturbances. We expect to initiate IPS observations by early 2003.