PWI-SPEC: an optical, multi-resolution spectrograph optimised for high fibre-count astrophotonic wavefront sensing and imaging instruments

Abstract

Astrophotonic instruments have seen a recent surge of interest, including photonic integrated circuits and photonic lantern wavefront sensors and imagers. Their advancement, however, requires measurement of an ever-growing number of SM outputs, with specific spectral and temporal sampling demands, necessitating a spectrograph design dissimilar to current general purpose astronomical spectrographs. PWI-SPEC is an optical spectrograph being built at Astralis-USyd and SAIL for the Photonic Wavefront Imager (PWI) module of the MagAO-X extreme adaptive optics system, purpose-designed to accept 100s of SMFs by using a unique rotated 2D fibre matrix array, and offer both lower- and higher-resolution modes tailored to wavefront sensing and imaging respectively. The final spectra are imaged at optimal pixel sampling and separation onto an Andor CB2 sCMOS camera which allows 100 SMFs at low spectral resolution (R=136) to be read out at ~1000 frames per second, with 1.4 electrons read noise.

Authors 12

1. Akira Rodziewicz-Ryan

   The University of Sydney

   Affiliation as printed

   Astralis, Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

2. Barnaby R. M. Norris

   The University of Sydney

   Affiliation as printed

   Astralis, Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

3. Christopher H. Betters

   The University of Sydney

   Affiliation as printed

   Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

4. Julia J. Bryant

   The University of Sydney

   Affiliation as printed

   Astralis, Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

5. Laird M. Close

   University of Arizona

   Affiliation as printed

   The Univ. of Arizona (United States)

6. Daniel S. Dahl

   The University of Sydney

   Affiliation as printed

   Astralis, Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

7. Olivier Guyon

   University of Arizona

   Affiliation as printed

   The Univ. of Arizona (United States)

8. Sebastiaan Y. Haffert Aachen Leiden Univ. (Netherlands)

   Leiden University

   Affiliation as printed

   Leiden Univ. (Netherlands)

9. Sergio León-Saval

   The University of Sydney

   Affiliation as printed

   Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

10. Nathan K. Long

    The University of Sydney

    Affiliation as printed

    Astralis, Sydney Institute for Astronomy, The Univ. of Sydney (Australia)

11. Jared R. Males

    University of Arizona

    Affiliation as printed

    The Univ. of Arizona (United States)

12. Andrew Ross‐Adams

    The University of Sydney

    Affiliation as printed

    Sydney Institute for Astronomy, The Univ. of Sydney (Australia)