X-RAY Periodicity in AGN

  title={X-RAY Periodicity in AGN},
  author={Karen Marie Leighly},
  journal={Astrophysics and Space Science},
  • K. Leighly
  • Published 27 December 2004
  • Physics
  • Astrophysics and Space Science
Significant (marginal) detections of periodic signals have been recently reported in 3 (4) Active Galactic Nuclei. Three of the detections were obtained from long EUVE light curves of moderate-luminosity Seyfert galaxies; the fourth was discovered in Chandra data from the low-luminosity Seyfert 1 galaxy NGC 4395. When compared with Cyg X-1, I find that the period is related to the luminosity as P∝ L2/3 rather than the expected one-to-one relationship. This result might be explained if the QPO… 

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