Interferometric Space Missions for the Search for Terrestrial Exoplanets: Requirements on the Rejection Ratio

The requirements on space missions designed to study Terrestrial exoplanets are discussed. We then investigate whether the design of such a mission, specifically the Darwin nulling interferometer, can be carried out in a simplified scenario. The key element here is accepting somewhat higher levels of stellar leakage. We establish detailed requirements resulting from the scientific rationale for the mission, and calculate detailed parameters for the stellar suppression required to achieve those requirements. We do this utilizing the Darwin input catalogue. The dominating noise source for most targets in this sample is essentially constant for all targets, while the leakage diminishes with the square of the distance. This means that the stellar leakage has an effect on the integration time only for the nearby stars, while for the more distant targets its influence decreases significantly. We assess the impact of different array configurations and nulling profiles and identify the stars for which the detection efficiency can be maximized.Comment: 21 pages, 8 figures; TBP in Astrophysics and Space Science 200

IF Fiber Optics and Digital Correlating Spectrometer on the JCMT-CSO Interferometer

This paper describes the delay lines designed and built for the JCMT-CSO submillimeter interferometer located on the summit of Mauna Kea, Hawaii and described in the paper by Carlstrom et al. in these proceedings.One of the major features of the project is the use of fiber optics instead of coaxial cable to bring the IF signals (l-2GHz) from the receivers to the spectral line correlator via a set of fiber optic delay lines. Optical fiber now has many advantages over coax including very large bandwidth, low loss, economical cost and size and immunity to electrical interference.Soares et al. (these proceedings) describe a delay line system that can be used with a broadband continuum correlator requiring very fine delay steps The JCMT-CSO interferometer was intended to be used primarily with a digital correlating spectrometer that has a range of built-in delays, greatly easing the demand on delay line resolution.</jats:p

Introduction to the JCMT-CSO Interferometer

The James Clerk Maxwell Telescope (JCMT) and the Caltech Submillimeter Observatory (CSO) are located 160m apart on Mauna Kea, Hawaii. Recently they have been linked together to allow the first submillimetre interferometric observations (between 300GHz and 490GHz, soon to 690GHz). Submillimetre observations can be used to probe the physical conditions of molecular clouds and dust in starforming regions. Lines from rotational transitions of molecules such as CO, HCN and HCO+ trace densities, temperatures and masses of molecular gas. The thermal emission of cold dust, typically found in dense clouds, also peaks in the submm regime.</jats:p

New technologies for exoplanet detection with mid-IR interferometers

This paper provides an overview of technology development for the Terrestrial Planet Finder Interferometer (TPF-I). TPF-I is a mid-infrared space interferometer being designed with the capability of detecting Earth-like planets in the habitable zones around nearby stars

Darwin—an experimental astronomy mission to search for extrasolar planets

International audienceAs a response to ESA call for mission concepts for its Cosmic Vision 2015–2025 plan, we propose a mission called Darwin. Its primary goal is the study of terrestrial extrasolar planets and the search for life on them. In this paper, we describe different characteristics of the instrument