
I will introduce a conceptually new type of telescope array and discuss its scientific applications, including one entirely novel signature to look for dark matter structures at sub-stellar masses.
The idea is based on a forthcoming proposal for an optical-path modification of astronomical intensity interferometers. This alteration introduces an effective time delay in the two-photon interference amplitude, splitting the main intensity correlation fringe into others at finite opening angles, allowing for differential astrometry of multiple compact sources such as stars or quasar images. Combined with other recent technological advances in spectroscopy and fast single-photon detection, a
ground-based time-delay intensity interferometer array would be capable of microarcsecond resolution (and even better light-centroiding accuracy) on bright sources separated by a few arcseconds.
I will lay out the theory, technical requirements, and scientific potential of time-delay intensity interferometry, and discuss the scientific potential. Promising applications include astrometric microlensing of stars and quasar images, binary-orbit characterization, exoplanet detection, Galactic acceleration measurements, calibration of the cosmic distance ladder, all at unprecedented relative astrometric precision.
Host: Yuan Xin (yuan.xin@yale.edu)