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arXiv · 2012.08563

Optical aspects of Near-Infrared Imager Spectrometer and Polarimeter instrument (NISP)

Archita Rai·Shashikiran Ganesh·Sukamal K. Paul·Prashanth K. Kasarla·Prachi V. Prajapati·Deekshya R. Sarkar·Alka Singh·Pitambar S. Patwal·Hitesh K L Adalja·Satya N. Mathur·Sachindra Naik·Amish B. Shah·Kiran S. Baliyan
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Abstract

As a Near-IR instrument to PRL's upcoming 2.5 m telescope, NISP is designed indigeniously at PRL to serve as a multifaceted instrument. Optical, Mechanical and Electronics subsystems are being designed and developed in-house at PRL. It will consist of imaging, spectroscopy and imaging-polarimetry mode in the wavelength bands Y, J, H, Ks i.e. 0.8 - 2.5 micron. The detector is an 2K x 2K H2RG (MCT) array detector from Teledyne, which will give a large FOV of 10' x 10' in the imaging mode. Spectroscopic modes with resolving power of R ~ 3000, will be achieved using grisms. Spectroscopy will be available in single order and a cross-dispersed mode shall be planned for simultaneous spectra. The instrument enables multi-wavelength imaging-polarimetry using Wedged-Double Wollaston (WeDoWo) prisms to get single shot Stokes parameters (I, Q, U) for linear polarisation simultaneously, thus increasing the efficiency of polarisation measurements and reducing observation time.

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Archita Rai, Shashikiran Ganesh, Sukamal K. Paul, Prashanth K. Kasarla, Prachi V. Prajapati, Deekshya R. Sarkar, Alka Singh, Pitambar S. Patwal, Hitesh K L Adalja, Satya N. Mathur, Sachindra Naik, Amish B. Shah, Kiran S. Baliyan. 2020-12-15. Optical aspects of Near-Infrared Imager Spectrometer and Polarimeter instrument (NISP). https://doi.org/10.1117/12.2560988

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