Experimental searches for the thermal radiation from analogue black holes
require the measurement of very low temperatures in regimes where other thermal
noises may interfere or even mimic the sought-after effect. In this letter, we
parameterize the family of bosonic thermal channels which give rise to such
thermal effects and show that by use of coherent states and homodyne detection
one can rule out the non-Hawking contributions and identify those candidate
sources which arise from Hawking-like processes.Comment: 5 pages, 2 figure