Current Science

Open Access Open Access  Restricted Access Subscription Access

Scanning Sky Monitor On-Board AstroSat


Affiliations
1 Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
2 Indian Space Research Organisation Headquarters, Department of Space, Antariksh Bhavan, New BEL Road, Bengaluru 560 231, India
3 Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India
4 Spacecraft Mechanisms Group, ISAC, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India
5 Control and Digital Electronics Group, ISAC, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India
6 Vikram Sarabhai Space Center, Thiruvananthapuram 695 022, India
 

Scanning Sky Monitor (SSM) on-board AstroSat is a wide-field imager to monitor the X-ray sky in the energy band 2.5-10 keV. The primary science objective of SSM is to detect and locate transient X-ray sources in the sky. Once detected the information is to be provided to the astronomical community for follow-up observations to do a more detailed study of the source. Long-term monitoring of known X-ray transient sources is also one of the science objectives of SSM. The instrument constitutes three units of 1D positionsensitive propotional counters with coded masks on each, all three mounted on a platform capable of rotation to scan about 50% of the sky in one full rotation. The angular resolution of each unit in SSM is 12' x 2.5°. Sensitivity of SSM is ~30 milliCrab at 3 sigma in 10 min integration time. This article briefly discusses the instrument and a few early results since the launch of AstroSat.

Keywords

AstroSat, Crab, Scanning Sky Monitor, X-Ray Transient Sources.
User
Notifications
Font Size

  • Agrawal, P. C., A broad spectral band Indian Astronomy satellite AstroSat. Adv. Space Res., 2006, 38, 29892994.

  • Singh, K. P. et al., AstroSat mission. Proc. SPIE, 2014, 91442T, 9144-100; doi:10.1117/12.2062667.

  • Levine, A. M. et al., First results from the All-Sky Monitor on the Rossi X-ray Timing Explorer. ApJ, 1996, 469, L33.

  • Seetha, S. et al., The Scanning Sky Monitor (SSM) on AstroSat. Adv. Space Res., 2006, 38, 2995–2998.

  • Matsuoka, M. et al., The MAXI mission on the ISS: science and instruments for monitoring All-sky X-ray images. PASJ, 2009, 61, 999.

  • Balaji, K., Narendra, S., Nagesh, G., Sridharamurthy, V. and Bhat, N. C., Development of mechanisms for AstroSat. In Proceedings of the 5th National Seminar and Exhibition on Aerospace and Related Mechanisms, ISRO Satellite Centre, Bengaluru, 18–19 November 2005, ARMS-05-MSA-02, pp. 67–73.

  • Ramadevi, M. C., Seetha, S., Babu, V. C., Ashoka, B. N. and Sreekumar, P., Optimization of gas proportional counters for Scanning Sky Monitor (SSM) onboard AstroSat. Adv. Space Res., 2006, 38, 3002–3004.

  • Ramadevi, M. C. et al., Scanning sky monitor (SSM) on-board AstroSat. Exp. Astron., 2017, doi:10.1007/s10686-017-9536-3.

  • Ramadevi, M. C. et al., Early in-orbit performance of Scanning Sky Monitor onboard AstroSat. J. Astrophys. Astr., 2016; doi:12.3456/s78910-011-012-3.

  • Ramadevi, M. C. et al., Detection of beta-class variability in black hole source GRS 1915+105 by AstroSat Scanning Sky Monitor. The Astronomer’s Telegram ATel #8185, 2015.


Abstract Views: 371

PDF Views: 134




  • Scanning Sky Monitor On-Board AstroSat

Abstract Views: 371  |  PDF Views: 134

Authors

M. C. Ramadevi
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
S. Seetha
Indian Space Research Organisation Headquarters, Department of Space, Antariksh Bhavan, New BEL Road, Bengaluru 560 231, India
Dipankar Bhattacharya
Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India
B. T. Ravishankar
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
N. Sitaramamurthy
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
G. Meena
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
M. Ramakrishna Sharma
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Ravi Kulkarni
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
V. Chandra Babu
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Kumar
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Brajpal Singh
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Anand Jain
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Reena Yadav
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
S. Vaishali
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
B. N. Ashoka
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
Anil Agarwal
Space Astronomy Group, SSIF, ISITE Campus, Karthik Nagar, Outer Ring Road, ISRO Satellite Centre, Bengaluru 560 037, India
K. Balaji
Spacecraft Mechanisms Group, ISAC, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India
Manoj Kumar
Control and Digital Electronics Group, ISAC, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India
Prashanth Kulshresta
Control and Digital Electronics Group, ISAC, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India
Pankaj Agarwal
Vikram Sarabhai Space Center, Thiruvananthapuram 695 022, India
Mathew Sebastian
Vikram Sarabhai Space Center, Thiruvananthapuram 695 022, India

Abstract


Scanning Sky Monitor (SSM) on-board AstroSat is a wide-field imager to monitor the X-ray sky in the energy band 2.5-10 keV. The primary science objective of SSM is to detect and locate transient X-ray sources in the sky. Once detected the information is to be provided to the astronomical community for follow-up observations to do a more detailed study of the source. Long-term monitoring of known X-ray transient sources is also one of the science objectives of SSM. The instrument constitutes three units of 1D positionsensitive propotional counters with coded masks on each, all three mounted on a platform capable of rotation to scan about 50% of the sky in one full rotation. The angular resolution of each unit in SSM is 12' x 2.5°. Sensitivity of SSM is ~30 milliCrab at 3 sigma in 10 min integration time. This article briefly discusses the instrument and a few early results since the launch of AstroSat.

Keywords


AstroSat, Crab, Scanning Sky Monitor, X-Ray Transient Sources.

References





DOI: https://doi.org/10.18520/cs%2Fv113%2Fi04%2F599-601