Laboratory results from an ultra-stable MID IR spectrometer for exo-planet atmosphere characterization

We have conducted a set of experiments on a TES (Transition-Edge Superconductor) bolometer detector array, demonstrating that a flux measurement stability better than 5 parts per million (ppm) over periods of hours to days, can be achieved with modest thermal stability requirements. This level of measurement stability is critical in enabling measurements of the atmospheric signatures of terrestrial-sized exoplanets around nearby K and M stars, including those in the star’s habitable zone. The demonstration uses a simple tungsten filament light bulb as the source, a photo diode operating at 0.5 μm as a stability monitor for the light bulb, and a grating spectrometer in the 5–15 μm wavelength range.