Correlated variability of Mkn 421 at X-ray and TeV wavelengths on timescales of hours

L. Maraschi; G. Fossati; F. Tavecchio; L. Chiappetti; A. Celotti; G. Ghisellini; P. Grandi; E. Pian; G. Tagliaferri; A. Treves; A. C. Breslin; J. H. Buckley; D. A. Carter-Lewis; M. Catanese; M. F. Cawley; D. J. Fegan; S. Fegan; J. Finley; J. Gaidos; T. Hall; A. M. Hillas; F. Krennrich; R. W. Lessard; C. Masterson; P. Moriarty; J. Quinn; J. Rose; F. Samuelson; T. C. Weekes

doi:10.1016/s0927-6505(99)00046-8

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arXiv · astro-ph/9902224

Correlated variability of Mkn 421 at X-ray and TeV wavelengths on timescales of hours

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Abstract

Mkn 421 was observed for about two days with BeppoSAX, prior to and partly overlapping the start of a 1 week continuous exposure with ASCA in April 1998, as part of a world-wide multiwavelength campaign. A pronounced, well defined, flare observed in X-rays was also observed simultaneously at TeV energies by the Whipple Observatory's 10 m gamma-ray telescope. These data provide the first evidence that the X-ray and TeV intensities are well correlated on time-scales of hours.

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L. Maraschi, G. Fossati, F. Tavecchio, L. Chiappetti, A. Celotti, G. Ghisellini, P. Grandi, E. Pian, G. Tagliaferri, A. Treves, A. C. Breslin, J. H. Buckley, D. A. Carter-Lewis, M. Catanese, M. F. Cawley, D. J. Fegan, S. Fegan, J. Finley, J. Gaidos, T. Hall, A. M. Hillas, F. Krennrich, R. W. Lessard, C. Masterson, P. Moriarty, J. Quinn, J. Rose, F. Samuelson, T. C. Weekes. 1999-02-16. Correlated variability of Mkn 421 at X-ray and TeV wavelengths on timescales of hours. https://doi.org/10.1016/s0927-6505(99)00046-8

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