The optical light curve of the Large Magellanic Cloud pulsar B0540-69 in 2009

作者:Gradari S*; Barbieri M; Barbieri C; Naletto G; Verroi E; Occhipinti T; Zoccarato P; Germana C; Zampieri L; Possenti A
来源:Monthly Notices of the Royal Astronomical Society, 2011, 412(4): 2689-2694.
DOI:10.1111/j.1365-2966.2010.18103.x

摘要

This paper reports a detailed analysis of the optical light curve of PSR B0540-69, the second brightest pulsar in the visible band, obtained in 2009 (January 18 and 20, and December 14, 15, 16 and 18) with the very high speed photon-counting photometer Iqueye mounted at the ESO 3.6-m New Technology Telescope in La Silla (Chile). The optical light curve derived by Iqueye shows a double structure in the main peak, with a rising edge steeper than the trailing edge. The double peak can be fitted by two Gaussians with the same height and full width at half-maximum of 13.3 and 15.5 ms, respectively. Our new values of spin frequencies allow us to extend by 3.5 yr the time interval over which a reliable estimate of frequency first and second derivatives can be performed. A discussion of implications for the braking index and age of the pulsar is presented. A value of n = 2.087 +/- 0.007 for the overall braking index from 1987 to 2009 is derived. The braking index corrected age is confirmed at around 1700 yr.

  • 出版日期2011-4