Negative Results with the Magellanic Stream

As mentioned in 'External Galaxies', there is a large 'stream' of HI high velocity clouds (HVCs) associated with the Small and Large Magellanic Clouds which extends over a wide arc in the sky as shown by the green curve below...

...note the SMC and LMC positions at the right-hand end of the curve.

The 3 m TVRO dish was positioned and the data acquisition timed to observe the position in the stream as marked by the purple dot.

A positive result was not expected due to the weak signal, but it was considered to be worth a try.

The selected position in the stream is shown in LAB Survey results for simulated 30 m and 3 m dish diameters...

...while focussing on the range from -300 km/s to -100 km/s shows a peak temperature of about 0.12 K using a 3 m dish...

...which indicates it is much below the results from the LMC...

...by a factor of 17 dB.

So the negative result is hardly a surprise.

Due to the high level of RFI at this location (even at 1.4 GHz), searching for weak signals is not practical.