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arXiv · astro-ph/9807314

Gamma-Ray Burst 980329 and its X-Ray Afterglow

J. J. M. in 't Zand·L. Amati·L. A. Antonelli·R. C. Butler·A. J. Castro-Tirado·A. Coletta·E. Costa·M. Feroci·F. Frontera·J. Heise·S. Molendi·L. Nicastro·A. Owens·E. Palazzi·E. Pian·L. Piro·G. Pizzichini·M. J. S. Smith·M. Tavani
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Abstract

GRB 980329 is the brightest gamma-ray burst detected so far with the Wide Field Cameras aboard BeppoSAX, both in gamma-rays and X-rays. With respect to its fluence (2.6 X 10**-5 erg/s/cm**2 in 50 to 300 keV) it would be in the top 4% of gamma-ray bursts in the 4B catalog (Meegan et al. 1998). The time-averaged burst spectrum from 2 to 20 and 70 to 650 keV can be well described by the empirical model of Band et al. (1993). The resulting photon index above the break energy is exceptionally hard at -1.32 +/- 0.03. An X-ray afterglow was detected with the narrow-field instruments aboard BeppoSAX 7 h after the event within the error box as determined with the Wide Field Cameras. Its peak flux is (1.4 +/- 0.2) X 10**-12 erg/s/cm**2 (2 to 10 keV). The afterglow decayed according to a power law function with an index of -1.35 +/- 0.03. GRB 980329 is characterized by being bright and hard, and lacking strong spectral evolution.

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J. J. M. in 't Zand, L. Amati, L. A. Antonelli, R. C. Butler, A. J. Castro-Tirado, A. Coletta, E. Costa, M. Feroci, F. Frontera, J. Heise, S. Molendi, L. Nicastro, A. Owens, E. Palazzi, E. Pian, L. Piro, G. Pizzichini, M. J. S. Smith, M. Tavani. 1998-07-30. Gamma-Ray Burst 980329 and its X-Ray Afterglow. https://doi.org/10.1086/311620

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