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Title: Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat

Abstract

We present the calibration and background model for the Large Area X-ray Proportional Counter (LAXPC) detectors on board AstroSat . The LAXPC instrument has three nominally identical detectors to achieve a large collecting area. These detectors are independent of each other, and in the event analysis mode they record the arrival time and energy of each photon that is detected. The detectors have a time resolution of 10 μ s and a dead-time of about 42 μ s. This makes LAXPC ideal for timing studies. The energy resolution and peak channel-to-energy mapping were obtained from calibration on the ground using radioactive sources coupled with GEANT4 simulations of the detectors. The response matrix was further refined from observations of the Crab after launch. At around 20 keV the energy resolution of the detectors is 10%–15%, while the combined effective area of the three detectors is about 6000 cm{sup 2}.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1];  [2];  [3];  [4]; ;  [5] more »; « less
  1. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)
  2. UM-DAE Centre of Excellence for Basic Sciences, University of Mumbai, Kalina, Mumbai 400098 (India)
  3. University of Mumbai, Kalina, Mumbai 400098 (India)
  4. Department of Astronomy and Astrophysics, Raman Research Institute, Bengaluru 560080 (India)
  5. Inter-University Centre for Astronomy and Astrophysics, Pune 411007 (India)
Publication Date:
OSTI Identifier:
22661109
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 231; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CALIBRATION; COMPUTERIZED SIMULATION; CRAB NEBULA; DEAD TIME; ENERGY RESOLUTION; G CODES; KEV RANGE; MAPPING; PHOTONS; PROPORTIONAL COUNTERS; RADIATION SOURCES; SPACE; SPACE VEHICLES; TIME RESOLUTION; X RADIATION; X-RAY DETECTION

Citation Formats

Antia, H. M., Yadav, J. S., Chauhan, Jai Verdhan, Chitnis, Varsha, Dedhia, Dhiraj, Shah, Parag, Gujar, V. M., Katoch, Tilak, Kurhade, V. N., Madhwani, Pankaj, Manojkumar, T. K., Nikam, V. A., Pandya, A. S., Parmar, J. V., Pawar, D. M., Agrawal, P. C., Manchanda, R. K., Paul, Biswajit, Pahari, Mayukh, Misra, Ranjeev, and and others. Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat. United States: N. p., 2017. Web. doi:10.3847/1538-4365/AA7A0E.
Antia, H. M., Yadav, J. S., Chauhan, Jai Verdhan, Chitnis, Varsha, Dedhia, Dhiraj, Shah, Parag, Gujar, V. M., Katoch, Tilak, Kurhade, V. N., Madhwani, Pankaj, Manojkumar, T. K., Nikam, V. A., Pandya, A. S., Parmar, J. V., Pawar, D. M., Agrawal, P. C., Manchanda, R. K., Paul, Biswajit, Pahari, Mayukh, Misra, Ranjeev, & and others. Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat. United States. doi:10.3847/1538-4365/AA7A0E.
Antia, H. M., Yadav, J. S., Chauhan, Jai Verdhan, Chitnis, Varsha, Dedhia, Dhiraj, Shah, Parag, Gujar, V. M., Katoch, Tilak, Kurhade, V. N., Madhwani, Pankaj, Manojkumar, T. K., Nikam, V. A., Pandya, A. S., Parmar, J. V., Pawar, D. M., Agrawal, P. C., Manchanda, R. K., Paul, Biswajit, Pahari, Mayukh, Misra, Ranjeev, and and others. Sat . "Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat". United States. doi:10.3847/1538-4365/AA7A0E.
@article{osti_22661109,
title = {Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat},
author = {Antia, H. M. and Yadav, J. S. and Chauhan, Jai Verdhan and Chitnis, Varsha and Dedhia, Dhiraj and Shah, Parag and Gujar, V. M. and Katoch, Tilak and Kurhade, V. N. and Madhwani, Pankaj and Manojkumar, T. K. and Nikam, V. A. and Pandya, A. S. and Parmar, J. V. and Pawar, D. M. and Agrawal, P. C. and Manchanda, R. K. and Paul, Biswajit and Pahari, Mayukh and Misra, Ranjeev and and others},
abstractNote = {We present the calibration and background model for the Large Area X-ray Proportional Counter (LAXPC) detectors on board AstroSat . The LAXPC instrument has three nominally identical detectors to achieve a large collecting area. These detectors are independent of each other, and in the event analysis mode they record the arrival time and energy of each photon that is detected. The detectors have a time resolution of 10 μ s and a dead-time of about 42 μ s. This makes LAXPC ideal for timing studies. The energy resolution and peak channel-to-energy mapping were obtained from calibration on the ground using radioactive sources coupled with GEANT4 simulations of the detectors. The response matrix was further refined from observations of the Crab after launch. At around 20 keV the energy resolution of the detectors is 10%–15%, while the combined effective area of the three detectors is about 6000 cm{sup 2}.},
doi = {10.3847/1538-4365/AA7A0E},
journal = {Astrophysical Journal, Supplement Series},
number = 1,
volume = 231,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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