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arXiv · 1106.0323

Detection and Imaging of the Crab Nebula with the Nuclear Compton Telescope

M. S. Bandstra·E. C. Bellm·S. E. Boggs·D. Perez-Becker·A. Zoglauer·H. -K. Chang·J. -L. Chiu·J. -S. Liang·Y. -H. Chang·Z. -K. Liu·W. -C. Hung·M. -H. A. Huang·S. J. Chiang·R. -S. Run·C. -H. Lin·M. Amman·P. N. Luke·P. Jean·P. von Ballmoos·C. B. Wunderer
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Abstract

The Nuclear Compton Telescope (NCT) is a balloon-borne Compton telescope designed for the study of astrophysical sources in the soft gamma-ray regime (200 keV--20 MeV). NCT's ten high-purity germanium crossed-strip detectors measure the deposited energies and three-dimensional positions of gamma-ray interactions in the sensitive volume, and this information is used to restrict the initial photon to a circle on the sky using the Compton scatter technique. Thus NCT is able to perform spectroscopy, imaging, and polarization analysis on soft gamma-ray sources. NCT is one of the next generation of Compton telescopes --- so-called compact Compton telescopes (CCTs) --- which can achieve effective areas comparable to COMPTEL's with an instrument that is a fraction of the size. The Crab Nebula was the primary target for the second flight of the NCT instrument, which occurred on 17--18 May 2009 in Fort Sumner, New Mexico. Analysis of 29.3 ks of data from the flight reveals an image of the Crab at a significance of 4-sigma. This is the first reported detection of an astrophysical source by a CCT.

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M. S. Bandstra, E. C. Bellm, S. E. Boggs, D. Perez-Becker, A. Zoglauer, H. -K. Chang, J. -L. Chiu, J. -S. Liang, Y. -H. Chang, Z. -K. Liu, W. -C. Hung, M. -H. A. Huang, S. J. Chiang, R. -S. Run, C. -H. Lin, M. Amman, P. N. Luke, P. Jean, P. von Ballmoos, C. B. Wunderer. 2011-06-01. Detection and Imaging of the Crab Nebula with the Nuclear Compton Telescope. https://doi.org/10.1088/0004-637x/738/1/8

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