REACH version 1 switchard (discontinued)
SCExAO fed IRD
The ability to directly image planetary system and conduct detailed spectroscopic analysis can refine our planetary formation model including their internal structure and atmospheric chemical composition.Very few planets have been directly imaged. The challenge lies ahead is being able to see a companion many orders of magnitude fainter at very small. Exoplanet imaging and spectroscopy requires excellent wavefront correction and calibration. At Subaru telescope, this can be achieved by extracting well corrected light from SCExAO and injecting it into a high resolution spectrometer such as IRD (Infrared Doppler Spectrometer). IRD is a high precision radial velocity instrument. It has a maximum resolution of R=70,000 in H band and covers a wide spectrum from from 0.97-1.75 µ
Image of the Infrared Doppler Spectrometer (IRD)
Single mode fiber bundle are to be used for simultaneous light collections from both the stars and planet. The central fiber can be used to collect the light from the planet, whereas the peripheral fibers could be used for cailbration of the stellar spectrum. Currently we are building an optical switchyard which gives flexibility in terms of choosing which fibers serve as positioning reference beam and speckle control. The central fiber is fed to the planet. All the peripheral fibers can be used for position reference or for speckle control. Light from all the cores in the MCF fiber bundle is fed into a V-groove assembly. The central fiber (used for planet) can be fed to one of the IRD’s SMF or MMFs using a dichroic or pickup mirror. Another pickup mirror is used to choose light from any of those peripheral fibers. Both these mirrors are mounted on 1-D translational stage which gives the liberty to choose light from any core to be fed to IRD. Below is a schematic representation of the optical switchyard.
Schematic representaion of optical switchyard
For more insightful information about this module please go through the following publications.
- Jovanovic, N., Cvetojevic, N., Schwab, C., Norris, B., Lozi, J., Gross, S., Betters, C., Singh, G., Guyon, O., Martinache, F., Doughty, D., Tuthill, P., 2016, "Efficiently feeding single-mode fiber photonic spectrographs with an extreme adaptive optics system: on-sky characterization and preliminary spectroscopy", Proc. of SPIE, 9908-0R
- M. Tamura, H. Suto, J. Nishikawa, T. Kotani, B. Sato, W. Aoki, T. Usuda, T. Kurokawa, K. Kashiwagi, S. Nishiyama, Y. Ikeda, D. Hall, K. Hodapp, J. Hashimoto, J. Morino, S. Inoue, Y. Mizuno, Y. Washizaki, Y. Tanaka, S. Suzuki, J. Kwon, T. Suenaga, D. Oh, N. Narita, E. Kokubo, Y. Hayano, H. Izumiura, E. Kambe, T. Kudo, N. Kusakabe, M. Ikoma, Ya. Hori, M. Omiya, H. Genda, A. Fukui, Y. Fujii, O. Guyon, H. Harakawa, M. Hayashi, M. Hidai, T. Hirano, M. Kuzuhara, M. Machida, T. Matsuo, T. Nagata, H. Ohnuki, M. Ogihara, S. Oshino, R. Suzuki, H. Takami, N. Takato, Y. Takahashi, C. Tachinami, H. Terada, "Infrared Doppler instrument for the Subaru Telescope (IRD)," Proc. SPIE 8446
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