First Very Low Frequency detection of short repeated bursts from magnetar SGR J1550-5418

Autor:	Tanaka, Y. T., Raulin, J. P., Bertoni, F. C. P., Fagundes, P. R., Chau, J., Schuch, N. J., Hayakawa, M., Hobara, Y., Terasawa, T., Takahashi, T.
Rok vydání:	2010
Předmět:	Astrophysics - High Energy Astrophysical Phenomena Astrophysics - Earth and Planetary Astrophysics
Druh dokumentu:	Working Paper
DOI:	10.1088/2041-8205/721/1/L24
Popis:	We report on the first detection of ionospheric disturbances caused by short repeated gamma-ray bursts from the magnetar SGR J1550-5418. Very low frequency (VLF) radio wave data obtained in South America clearly show sudden amplitude and phase changes at the corresponding times of eight SGR bursts. Maximum amplitude and phase changes of the VLF signals appear to be correlated with the gamma-ray fluence. On the other hand, VLF recovery timescales do not show any significant correlation with the fluence, possibly suggesting that the bursts' spectra are not similar to each other. In summary, the Earth's ionosphere can be used as a very large gamma-ray detector and the VLF observations provide us with a new method to monitor high energy astrophysical phenomena without interruption such as Earth Occultation. Comment: 14 pages, 4 figures, accepted by ApJL
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1008.3609 Zobrazit plný text záznamu View this record from Arxiv