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arXiv · 0903.1974

Strong bursts from the anomalous X-ray pulsar 1E 1547.0-5408 observed with the INTEGRAL/SPI Anti-Coincidence Shield

S. Mereghetti·D. Gotz·G. Weidenspointner·A. von Kienlin·P. Esposito·A. Tiengo·G. Vianello·G. L. Israel·L. Stella·R. Turolla·N. Rea·S. Zane
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Abstract

In January 2009, multiple short bursts of soft gamma-rays were detected from the direction of the anomalous X-ray pulsar 1E 1547.0-5408 by different satellites. Here we report on the observations obtained with the INTEGRAL SPI-ACS detector during the period with the strongest bursting activity. More than 200 bursts were detected at energies above 80 keV in a few hours on January 22. Among these, two remarkably bright events showed pulsating tails lasting several seconds and modulated at the 2.1 s spin period of 1E 1547.0-5408. The energy released in the brightest of these bursts was of a few 10^43 erg, for an assumed distance of 10 kpc. This is smaller than that of the three giant flares seen from soft gamma-ray repeaters, but higher than that of typical bursts from soft gamma-ray repeaters and anomalous X-ray pulsars.

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S. Mereghetti, D. Gotz, G. Weidenspointner, A. von Kienlin, P. Esposito, A. Tiengo, G. Vianello, G. L. Israel, L. Stella, R. Turolla, N. Rea, S. Zane. 2009-03-11. Strong bursts from the anomalous X-ray pulsar 1E 1547.0-5408 observed with the INTEGRAL/SPI Anti-Coincidence Shield. https://doi.org/10.1088/0004-637x%2F696%2F1%2Fl74

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