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arXiv · 1401.0545

AGN and quasar science with aperture masking interferometry on the James Webb Space Telescope

K. E. Saavik Ford·Barry McKernan·Anand Sivaramakrishnan·André R. Martel·Anton Koekemoer·David Lafrenière·Sébastien Parmentier
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Abstract

Due to feedback from accretion onto supermassive black holes (SMBHs), Active Galactic Nuclei (AGNs) are believed to play a key role in LambdaCDM cosmology and galaxy formation. However, AGNs' extreme luminosities and the small angular size of their accretion flows create a challenging imaging problem. We show James Webb Space Telescope's Near Infrared Imager and Slitless Spectrograph (JWST-NIRISS) Aperture Masking Interferometry (AMI) mode will enable true imaging (i.e. without any requirement of prior assumptions on source geometry) at ~65 mas angular resolution at the centers of AGNs. This is advantageous for studying complex extended accretion flows around SMBHs, and in other areas of angular-resolution-limited astrophysics. By simulating data sequences incorporating expected sources of noise, we demonstrate that JWST-NIRISS AMI mode can map extended structure at a pixel-to-pixel contrast of ~10^{-2} around an L=7.5 point source, using short exposure times (minutes). Such images will test models of AGN feedback, fuelling and structure (complementary with ALMA observations), and are not currently supported by any ground-based IR interferometer or telescope. Binary point source contrast with NIRISS is ~10^{-4} (for observing binary nuclei in merging galaxies), significantly better than current ground-based optical or IR interferometry. JWST-NIRISS' seven-hole non-redundant mask has a throughput of 15%, and utilizes NIRISS' F277W (2.77\micron), F380M (3.8\micron), F430M (4.3\micron), and F480M (4.8\micron) filters. NIRISS' square pixels are 65mas per side, with a field of view ~2\arcmin x 2\arcmin. We also extrapolate our results to AGN science enabled by non-redundant masking on future 2.4m and 16m space telescopes working at long-UV to near-IR wavelengths.

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K. E. Saavik Ford, Barry McKernan, Anand Sivaramakrishnan, André R. Martel, Anton Koekemoer, David Lafrenière, Sébastien Parmentier. 2014-01-02. AGN and quasar science with aperture masking interferometry on the James Webb Space Telescope. https://doi.org/10.1088/0004-637x/783/2/73

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