A new interferometer architecture combining nulling with phase closure measurements

Abstract

Imaging the direct light signal from a faint exoplanet against the overwhelming glare of its host star presents one of the fundamental challenges to modern astronomical instrumentation. Achieving sufficient signal-to-noise for detection by direct imaging is limited by three basic physical processes: aberration of the wavefronts (both instrumental and atmospheric), photon noise, and detector noise. In this paper, we advance a novel optical setup which synthesizes the advantages of two different techniques: nulling interferometry to mitigate photon noise, and closure phase to combat optical aberrations. Our design, which employs technology from integrated optics and photonics, is intended to combine the advantageous aspects of both a coronagraph and a non-redundant interferometer inside a single optical device. We show that such an instrument would have a dynamic range limited either by i) the readout noise (if perfect co-phasing), or ii) the photon noise due to stellar flux leakage (in the case of imperfect nulling). This concept is optimal when the readout noise is not the main limitation, ie, for space interferometry or for ground based observations of bright stellar hosts (apparent magnitude brighter than 10).

11 pages. Accepted by MNRAS

References in corpus (5)

• Phase Errors in Diffraction-Limited Imaging: Contrast Limits for Sparse Aperture Masking
• Starlight Demonstration of the Dragonfly Instrument: an Integrated Photonic Pupil Remapping Interferometer for High Contrast Imaging
• Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD104237
• High dynamic range imaging by pupil single-mode filtering and remapping
• The Importance of Phase in Nulling Interferometry and a Three Telescope Closure-Phase Nulling Interferometer Concept

Cited by in corpus (10)

• First on-sky demonstration of an integrated-photonic nulling-interferometer: The GLINT instrument
• The path towards high-contrast imaging with the VLTI: the Hi-5 project
• 2023 Astrophotonics Roadmap: pathways to realizing multi-functional integrated astrophotonic instruments
• Kernel-nulling for a robust direct interferometric detection of extrasolar planets
• Asgard/NOTT: L-band nulling interferometry at the VLTI I. Simulating the expected high-contrast performance
• Achromatic photonic tricouplers for application in nulling interferometry
• Kernel nullers for an arbitrary number of apertures
• The Carlina-type diluted telescope: Stellar fringes on Deneb
• Hi-5: a potential high-contrast thermal near-infrared imager for the VLTI
• Planet Formation Imager: Project Update