Speaker
Description
We present the design and initial results of a stellar intensity interferometer using small 0.25 m Newtonian-style telescopes in an urban backyard setting. The primary purpose of the interferometer is to measure the angular diameters of stars. Recent advances in low jitter time-tagging equipment and Single Photon Avalanche Detectors have made the detection of second-order correlation signals, necessary for Intensity Interferometry as demonstrated by Hanbury Brown and Twiss in 1956, feasible with small telescopes. Using Sirius as a target star, we observe a strong second-order correlation spike with an integrated signal to noise ratio (SNR) ∼7 after 13.55 h of integration over a three-night period using a 3.3 m baseline. The measured signal agrees with the theoretical estimates of both coherence time, 𝜏coh = 0.74 ± 0.26 ps and SNR. We discuss the future expansion of this technique with multiple wavelengths simultaneously via a prism grating and multiple detectors.
External references
- 24100097
- b583b491-79c5-4080-93b5-78f2b8d8aeac
