Aditya-L1 is the first Indian space mission to explore the Sun and solar atmosphere with seven multi-wavelength payloads, with Visible Emission Line Coronagraph (VELC) being the prime payload. It is an internally occulted coronagraph with four channels to image the Sun at 5000 \AA~ in the field of view 1.05 - 3 \rsun, and to pursue spectroscopy at 5303 \AA, 7892 \AA~ and 10747 \AA~ channels in the FOV (1.05 - 1.5 \rsun). In addition, spectropolarimetry is planned at 10747 \AA~ channel. Therefore, VELC has three sCMOS detectors and one InGaAs detector. In this article, we aim to describe the technical details and specifications of the detectors achieved by way of thermo-vacuum calibration at the CREST campus of the Indian Institute of Astrophysics, Bangalore, India. Furthermore, we report the estimated conversion gain, full-well capacity, and readout noise at different temperatures. Based on the numbers, it is thus concluded that it is essential to operate the sCMOS detectors and InGaAs detectors at −5∘ and −17∘ C, respectively, at the spacecraft level.
@article{arxiv.2403.07373,
title = {Calibration of VELC detectors on-board Aditya-L1 mission},
author = {Shalabh Mishra and K. Sasikumar Raja and Sanal Krishnan V U and Venkata Suresh Narra and Bhavana Hegde S and Utkarsha D. and Muthu Priyal and Pawan Kumar S and Natarajan V and Raghavendra Prasad B and Jagdev Singh and Umesh Kamath P and Kathiravan S and Vishnu T and Suresha and Savarimuthu P and Jalshri H Desai and Rajiv Kumaran and Shiv Sagar and Sumit Kumar and Inderjeet Singh Bamrah and Amit Kumar},
journal= {arXiv preprint arXiv:2403.07373},
year = {2024}
}
Comments
Accepted for publication in Experimental Astronomy; 13 Pages, 5 Figures and 8 Tables