Indian Institute of Astrophysics  >
IIAP Publications >
IIAP Publications >

Please use this identifier to cite or link to this item:

Title: Pointing of HAGAR telescope mirrors
Authors: Gothe, K. S
Prabhu, T. P
Vishwanath, P. R
Acharya, B. S
Srinivasan, R
Chitnis, V. R
Kamath, P. U
Srinivasulu, G
Saleem, F
Kemkar, P. M. M
Mahesh, P. K
Gabriel, F
Manoharan, J
Dorji, N
Dorjai, T
Angchuk, D
D'souza, A. I
Duhan, S. K
Nagesh, B. K
Rao, S. K
Sharma, S. K
Singh, B. B
Sudersanan, P. V
Thsering, M. T
Upadhya, S. S
Anupama, G. C
Britto, R. J
Cowsik, R
Saha, L
Shukla, A
Keywords: Telescope pointing
γ-ray astronomy
Pointing model
Atmospheric Cherenkov telescopes
Issue Date: Apr-2013
Publisher: Springer
Citation: Experimental Astronomy, Vol. 35, No. 3, pp. 489-506
Abstract: An array of seven atmospheric Cherenkov telescopes was commissioned at a high altitude site in Hanle in the Ladakh region of the Himalayas. The array called HAGAR has been designed to observe celestial γ-rays of energy >100 GeV. Each telescope is altitude-azimuth mounted and carries seven parabolic mirrors whose optic axes are co-aligned with the telescope axis. The telescopes point and track a celestial source using a PC-based drive control system. Two important issues in positioning of each HAGAR telescope are pointing accuracy of telescope axis and co-alignment of mirrors’ optic axes with the telescope axis. We have adopted a three pronged strategy to address these issues, namely use of pointing models to improve pointing accuracy of the telescopes, RA-DEC scan technique to measure the pointing offsets of the mirrors and mechanical fine-tuning of off-axis mirrors by sighting a distant stationary light source. This paper discusses our efforts in this regard as well as the current status of pointing and monitoring of HAGAR telescopes.
Description: Restricted Access
The original publication is available at
ISSN: 1572-9508
Alternative Location:
Copyright: © Springer
Appears in Collections:IIAP Publications

Files in This Item:

File Description SizeFormat
Pointing of HAGAR telescope mirrors.pdfRestricted Access530.83 kBAdobe PDFView/Open

Items in IIAP Repository are protected by copyright, with all rights reserved, unless otherwise indicated.


Valid XHTML 1.0! DSpace Software Copyright © 2002-2007 MIT and Hewlett-Packard - Feedback