A DECLINE IN THE NONTHERMAL X-RAY EMISSION FROM CASSIOPEIA A

@article{Patnaude2011ADI,
  title={A DECLINE IN THE NONTHERMAL X-RAY EMISSION FROM CASSIOPEIA A},
  author={Daniel J. Patnaude and Jacco Vink and J. Martin Laming and Robert A. Fesen},
  journal={The Astrophysical Journal},
  year={2011},
  volume={729}
}
We present new Chandra ACIS-S3 observations of Cassiopeia A which, when combined with earlier ACIS-S3 observations, show evidence for a steady ~1.5%-2% yr–1 decline in the 4.2-6.0 keV X-ray emission between the years 2000 and 2010. The computed flux from exposure corrected images over the entire remnant showed a 17% decline over the entire remnant and a slightly larger (21%) decline from regions along the remnant's western limb. Spectral fits of the 4.2-6.0 keV emission across the entire… Expand

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