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Cosmic Explosions (Optical)

Kulkarni, S. R. (2011) Cosmic Explosions (Optical). In: New Horizons in Time-Domain Astronomy. IAU Symposium Proceedings Series . Vol.7. No.285. Cambridge University Press , New York, pp. 55-61. ISBN 978-1-107-01985-0.

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One of the principal motivations of wide-field and synoptic surveys is the search for, and study of, transients. By transients I mean those sources that arise from the background, are detectable for some time, and then fade away to oblivion. Transients in distant galaxies need to be sufficiently bright as to be detectable, and in almost all cases those transients are catastrophic events, marking the deaths of stars. Exemplars include supernovæ and gamma-ray bursts. In our own Galaxy, the transients are strongly variable stars, and in almost all cases are at best cataclysmic rather than catastrophic. Exemplars include flares from M dwarfs, novæ of all sorts (dwarf novæ, recurrent novæ, classical novæ, X-ray novæ) and instabilities in the surface layers of stars such as S Dor or η Carina. In the nearby Universe (say out to the Virgo cluster) we have sufficient sensitivity to see novæ. In §1 I review the history of transients (which is intimately related to the advent of wide-field telescopic imaging). In §2 I summarize wide-field imaging projects, and I then review the motivations that led to the design of the Palomar Transient Factory (PTF). Next comes a summary of the astronomical returns from PTF (§3), and that is followed by lessons that I have learnt from PTF (§4). I conclude that, during this decade, the study of optical transients will continue to flourish (and may even accelerate as surveys at other wavelengths—notably radio, UV and X-ray—come on-line). Furthermore, it is highly likely that there will be a proliferation of highly-specialized searches for transients. Those searches may well remain active even in the era of LSST (§5). I end the article by discussing the importance of follow-up telescopes for transient object studies—a topical issue, given the Portfolio Review that is being undertaken in the US.

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Kulkarni, S. R.0000-0001-5390-8563
Additional Information:© 2012 International Astronomical Union. Published online: 20 April 2012. PTF is a collaboration of the following entities: California Institute of Technology, Lawrence Berkeley National Laboratory (LBNL), Weizmann Institute of Sciences, Las Cumbres Observatory Global Telescope, Columbia University, Oxford University, Infrared Processing & Analysis Center (IPAC) and UC Berkeley. LBNL is responsible for the image subtraction pipeline, IPAC for the photometric pipeline and U. C. Berkeley for the classification engine. I would like to acknowledge the National Astronomy Observatory of Japan and the Japan Society for Promotion of Science for hosting my sabbatical stay in Japan during which period this article was completed. I would like to thank all the members of the PTF experiment. It is their hard work and creativity that has made PTF productive. I would further like to acknowledge the key role played by the following in the PTF: L. Bildsten, J. Bloom, S. B. Cenko, A. Gal-Yam, M. Kasliwal, R. Laher, N. Law, P. Nugent, E. Ofek, R. Quimby and J. Surace. The hard-working and knowledgeable staff of Caltech Optical Observatories made it possible for rapid re-engineering of the focal plane of P48 and refurbishment of P48. The very low down-time, despite the age of P48 and P60, speaks superbly of the deep knowledge and hard work of the Palomar Mountain staff. D. Fox, B. Cenko and M. Kasliwal were in charge of the automation, robotization and optimization of P60, and E. Ofek was (and continues to be) the sequencer for P48. PTF got a great start with CFH12K, and I sincerely appreciate the generosity of the builders of CFH12K, Christian Veillet (the then Director of CFHT) and the CFHT Corporation. I would like to thank D. Frail, G. Helou and T. Prince for helping me debate strategies in this rapidly evolving field. Finally, I would like to acknowledge and thank W. Rosing, whose initial “investment” in PTF allowed me to garner funds from other parties and complete the funding for PTF in record time.
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Series Name:IAU Symposium Proceedings Series
Issue or Number:285
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Official Citation: S. R Kulkarni (2011). Cosmic Explosions (Optical). Proceedings of the International Astronomical Union, 7, pp 55-61 doi:10.1017/S174392131200021X
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:35278
Deposited By: Tony Diaz
Deposited On:14 Nov 2012 19:47
Last Modified:03 Oct 2019 04:26

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