Selected Radio Maps and Major Solar Radio Flares Measured at Metsaehovi in 1996-2001

摘要

The Metsahovi Radio Observatory, a separate research institute of the Helsinki University of Technology since 1988, operates two radio telescopes for solar research. Telescopes are located at Metsahovi, Kylmala. First solar measurements were done in 1976. The 14-m diameter radio telescope is a multi-purpose telescope, which is used for extragalactic research, VLBI, and solar research. Annually 5-15 weeks are used for solar research. In measurements described in this report the frequency was 36.8 GHz. The beam size of the telescope is 2.4 arc min. The estimated quiet Sun level at this frequency is 7800 K. For the measurements either linear or logarithmic output can be selected. The receiver is room temperature Dicke-type receiver where Sun is measured against a room temperature wave guide load. The sensitivity of the receiver is good enough for 0.1 sfu resolution. In temperature scale the resolution is better than 100 K and it is limited by short term changes in the atmospheric attenuation. The digitized data is stored on a MicroVAX II computer.