  As spin caloritronic measurements become increasingly common techniques for
characterizing material properties, it is important to quantify potentially
confounding effects. We report measurements of the Nernst-Ettingshausen
response from room temperature to 5 K in thin film wires of Pt and W, metals
commonly used as inverse spin Hall detectors in spin Seebeck characterization.
Johnson-Nyquist noise thermometry is used to assess the temperature change of
the metals with heater power at low temperatures, and the thermal path is
analyzed via finite-element modeling. The Nernst-Ettingshausen response of W is
found to be approximately temperature-independent, while the response of Pt
increases at low temperatures. These results are discussed in the context of
theoretical expectations and the possible role of magnetic impurities in Pt.
