Millimetre-Wave Radio Source in Taurus

Abstract

RECENT microwave observations by Kuzmin and Salomonovich¹ and by myself of the radio emission from Taurus have revealed the presence of an unusual radio source located approximately 9 min. of arc east of Taurus-A. Kuzmin and Salomonovich observed the source with the 22-m. radiotelescope of the Lebedev Institute of Physics operating at 8-mm. wave-length and with a pencil beam-width of 2 min. of arc to the half-power points. While taking drift curves on Taurus-A, these workers detected a new source approximately 35^s east of Taurus-A. The reported flux density at 8-mm. wave-length is 1.30 × 10⁻²⁴ ± 25 per cent W./m.² (c.p.s.), the brightness temperature, T_B, is 7 ± 25 per cent ° K., the angular width in right ascension is 2.5 min. of arc and the flux density ratio to Taurus-A is 0.26. Kuzmin and Salomonovich conclude that the source is a thermal emitter with an emission measure of 2.7 × 10⁶, as would certainly be expected from a source initially discovered at 8-mm. wave-length.