In preparation of a large-scale nulling interferometry mission aiming to detect and characterize Earth-like exoplanets, it is required that key technologies are demonstrated in a space environment. Design trade-offs for a large mission have assumed long, reconfigurable baselines. However, it is uncertain that the same design performs best for a smaller mission with shorter, fixed baselines.
This research aims to compare the performance of three possible nulling configurations, a linear double Bracewell, a rectangular double Bracewell and a off-center kite shaped kernel nuller, on their ability to constrain the temperature, radius, and position of an exoplanet during the mission detection phase.
The configurations are compared by planetary signal simulations performed using the simulation software SCIFYsim. The configurations are compared based on three categories (1) performance for a single planet case, (2) the introduced correlations between planetary parameters, and (3) the performance in a two planet case.
The analysis indicates that the configurations performed similarly when modeling a single planet system, with the linear configuration showing a slight advantage. Regarding the parameter correlations, the kernel configuration exhibits the least correlations between fitted parameters. In the two-planet system, both the rectangular and kernel configurations achieve the highest accuracy in retrieving planetary parameters, though the overall performance remains relatively similar across configurations. Notably, despite the blurry signature of the two planet system in the matched filter map for the linear configuration, the fitting process is able to retrieve the planetary parameters.