Abstract
French (CNES) and Chinese (CNSA) space agencies collaborate to build the SVOM (Space-based multi-band Variable Object Monitor) mission due to be launched in 2021 to study gamma-ray bursts and high-energy transients. The SVOM prime instrument, ECLAIRs, will detect and localize GRBs autonomously as well as provide a spectral and temporal characterization of the GRB prompt emission. ECLAIRs is expected to detect around 200 GRBs during the 3 year nominal lifetime of the mission. ECLAIRs is a wide-field (\(\sim 2 \text {sr}\)) coded mask camera with a detection plane made of 8 independent sectors of 800 Schottky CdTe detectors working in the 4-150 keV energy range. Each sector is connected to independent readout electronics. In this paper, we focus on the study of the temporal performance and we estimate how dead time will affect bright transient lightcurves. We discuss the analytical model based on simulations over a large range of source count rates on a dedicated test bench. We show that dead time will not significantly affect ECLAIRs data, even for the brightest GRBs (3.7% of lost counts for a count rate of 105 counts.s− 1 over the detection plane in the energy range 4−150 keV) and our model can nicely correct the parts of the lightcurves which are the most affected by dead time effects for very bright GRBs.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
MacFadyen, A.I., Woosley, S.E.: Collapsars: gamma-ray bursts and explosions in failed supernovae. Astrophys. J. 524(1), 262 (1999)
G. ray burst Monitor, fermi, ligo collaboration, et al.: Gravitational waves and gamma-rays from a binary neutron star merger: Gw170817 and grb 170817a. The Astrophysical Journal Letters 848:L13, 27 (2017)
Paul, J., Wei, J., Basa, S., Zhang, S.N.: The chinese–french svom mission for gamma-ray burst studies. Comptes Rendus Physique 12(3), 298 (2011)
Godet, O., Nasser, G., Cordier, B., Mandrou, P., Barret, D., Triou, H., Pons, R., Amoros, C., Bordon, S., Gevin, O., et al.: (International society for optics and photonics) in SPIE astronomical telescopes+ instrumentation (2014)
Yongwei, D., Bobing, W., Yanguo, L., Yongjie, Z., Shuangnan, Z.: Svom gamma ray monitor, science China, physics, mechanics and astronomy (2009)
Götz, D., Adami, C., Basa, S., Beckmann, V., Burwitz, V., Chipaux, R., Cordier, B., Evans, P., Godet, O., Goosmann, R., Meidinger, N., Meuris, A., Motch, C., Nandra, K., O’Brien, P., Osborne, J.P., Perinati, E., Rau, A., Willingale, R., Mercier, K., Gonzalez, F.: . In: Proceedings of Swift: 10 years of discovery (SWIFT 10), held 2-5 December 2014 at La Sapienza University, Rome, Italy, id.74, pp. 74 (2014)
Tianzhou, W., Qiu, Y., Hongbo, C., Jingsong, D.: A fast onboard star-extraction algorithm optimized for the Svom visible telescope, science China, physics, mechanics and astronomy (2009)
Feng, T., Du, Z., Sun, Y., Wei, J., Bi, J., Liu, J.: . In: IEEE International Congress on (IEEE, 2017) in big data (BigData Congress), pp 224–231 (2017)
Wei, J., Cordier, B., Antier, S., Antilogus, P., Atteia, J.L., Bajat, A., Basa, S., Beckmann, V., Bernardini, M., Boissier, S., et al.: The deep and transient universe in the svom era: new challenges and opportunities-scientific prospects of the svom mission (2016)
Nasser, G.: Characterization of modules of the eclairs’ detection plane for the mission svom. Ph.D. thesis, université de Toulouse université Toulouse III-paul Sabatier (2015)
Gevin, O., Baron, P., Coppolani, X., Daly, F., Delagnes, E., Limousin, O., Lugiez, F., Meuris, A., Pinsard, F., Renaud, D.: Idef-x eclairs: a cmos asic for the readout of cdte and cdznte detectors for high resolution spectroscopy. IEEE Trans. Nucl. Sci. 56(4), 2351 (2009)
Yadav, J., Misra, R., Chauhan, J.V., Agrawal, P., Antia, H., Pahari, M., Dedhia, D., Katoch, T., Madhwani, P., Manchanda, R., et al.: Astrosat/laxpc reveals the high-energy variability of grs 1915 + 105 in the χ class. Astrophys. J. 833(1), 27 (2016)
Krimm, H.A., Holland, S.T., Corbet, R.H., Pearlman, A.B., Romano, P., Kennea, J.A., Bloom, J.S., Barthelmy, S.D., Baumgartner, W.H., Cummings, J.R., et al.: The swift/bat hard x-ray transient monitor. Astrophys. J. Suppl. Ser. 209(1), 14 (2013)
Palmer, D.M., Barthelmy, S., Gehrels, N., Kippen, R., Cayton, T., Kouveliotou, C., Eichler, D., Wijers, R., Woods, P., Granot, J., et al.: A giant γ-ray flare from the magnetar sgr 1806–20. Nature 434(7037), 1107 (2005)
Knoll, G.F.: Radiation detection and measurement. John Wiley & Sons, New York (1989)
Agostinelli, S., et al.: Geant4 user’s guide for application developers, dec. 2010. Nucl. Instr. Meth. A 506, 250 (2003)
Piran, T., et al.: Variability in gamma-ray bursts: a clue. Astrophys. J. 485 (1), 270 (1997)
Meegan, C., Lichti, G., Bhat, P., Bissaldi, E., Briggs, M.S., Connaughton, V., Diehl, R., Fishman, G., Greiner, J., Hoover, A.S., et al.: The fermi gamma-ray burst monitor. Astrophys. J. 702(1), 791 (2009)
Briggs, M.S., Paciesas, W.S., Pendleton, G.N., Meegan, C.A., Fishman, G.J., Horack, J.M., Brock, M., Kouveliotou, C., Hartmann, D.H., Hakkila, J.: Batse observations of the large-scale isotropy of gamma-ray bursts, The Astrophysical Journal (1996)
Antier-Farfar, S.: The Gamma-Ray Detection by Eclairs Telescope for the French Mission Svom. Ph.D. thesis, Université Paris-Saclay (2016)
Acknowledgements
This work is supported by the CNES and the région Midi-Pyrénées.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Bajat, A., Godet, O., Atteia, JL. et al. Characterizing the dead time of the ECLAIRs camera on board the mission SVOM. Exp Astron 46, 337–356 (2018). https://doi.org/10.1007/s10686-018-9606-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10686-018-9606-1