Mechanical aspects of Near-Infrared Imager Spectrometer and Polarimeter

Prashanth Kumar Kasarla; Pitamber Singh Patwal; Hitesh Kumar L. Adalja; Satya Narain Mathur; Deekshya Roy Sarkar; Alka Singh; Archita Rai; Prachi Vinod Prajapati; Sachindra Naik; Amish B. Shah; Shashikiran Ganesh; Kiran S. Baliyan

doi:10.1117/12.2561339

arXiv · 2012.08813

Mechanical aspects of Near-Infrared Imager Spectrometer and Polarimeter

Prashanth Kumar Kasarla·Pitamber Singh Patwal·Hitesh Kumar L. Adalja·Satya Narain Mathur·Deekshya Roy Sarkar·Alka Singh·Archita Rai·Prachi Vinod Prajapati·Sachindra Naik·Amish B. Shah·Shashikiran Ganesh·Kiran S. Baliyan

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Abstract

Near-infrared Imager Spectrometer and Polarimeter (NISP) is a camera, an intermediate resolution spectrograph and an imaging polarimeter being developed for upcoming 2.5m telescope of Physical Research Laboratory at Mount Abu, India. NISP is designed to work in the Near-IR (0.8-2.5 micron) using a H2RG detector. Collimator and camera lenses would transfer the image from the focal plane of the telescope to the detector plane. The entire optics, mechanical support structures, detector-SIDECAR assembly will be cooled to cryo-temperatures using an open cycle Liquid Nitrogen tank inside a vacuum Dewar. GFRP support structures would be used to isolate cryogenic system from the Dewar. Two layer thermal shielding would be used to reduce the radiative heat transfer. Molecular sieve (getter) would be used to enhance the vacuum level inside Dewar. Magnet-reedswitch combination are used for absolute positioning of filterwheels. Here we describe the mechanical aspects in detail.

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Prashanth Kumar Kasarla, Pitamber Singh Patwal, Hitesh Kumar L. Adalja, Satya Narain Mathur, Deekshya Roy Sarkar, Alka Singh, Archita Rai, Prachi Vinod Prajapati, Sachindra Naik, Amish B. Shah, Shashikiran Ganesh, Kiran S. Baliyan. 2020-12-16. Mechanical aspects of Near-Infrared Imager Spectrometer and Polarimeter. https://doi.org/10.1117/12.2561339

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