Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1771572 | Astroparticle Physics | 2006 | 10 Pages |
Abstract
We confirm a 23Â day periodicity during a large flare in 1997 for X-ray data of X-ray satellite RXTE all sky monitor (ASM), 2Â TeV gamma ray data from Utah Seven Telescope and HEGRA, with a Fourier analysis. We found the three results to be the same with a newly estimated error. We confirm the presence of a frequency dependent power (1/f noise) in a frequency-power diagram. Further, we calculated a chance probability of the occurrence of the 23Â day periodicity by considering the 1/f noise and obtained a chance probability 4.88Â ÃÂ 10â3 for the HEGRA data: this is more significant than the previous result by an order. We also obtained an indentical periodicity with another kind of timing analysis-epoch folding method for the ASM data and HEGRA data. We strongly suggest an existence of the periodicity. We divided the HEGRA data into two data sets, analyzed them with a Fourier method, and found an unstableness of the periodicity with a 3.4 sigma significance. We also analyzed an energy spectra of the X-ray data of a RXTE proportional counter array and we found that a combination of three physical parameters-a magnetic field, a Lorentz factor, and a beaming factor-is related to the periodicity.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Astronomy and Astrophysics
Authors
S. Osone,