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arXiv · astro-ph/0011298

Gamma-ray sources as relics of recent supernovae in the nearby Gould Belt

Abstract

The nearby, 30 to 40 Myr old, starburst region of the Gould Belt has formed numerous massive stars. Within its 300 pc radius, it produces core-collapse supernovae at an enhanced rate which is shown to be 75 to 95 Myr{-1} kpc{-2}, i.e. 3 to 5 times higher than the local Galactic rate, over the past and future few million years. A population of persistent, but unidentified, gamma-ray sources has been recently singled out at medium latitudes above 100 MeV. Their distribution across the sky is shown to be quite significantly and better correlated with the tilted Gould Belt than with other Galactic structures. As many as 40 +- 5 sources are statistically associated with the Belt at |b|> 5 deg. It is therefore proposed that these sources are part of the Belt and are relics of the Belt supernovae in the form of million-year old pulsars. Their presence stresses how active the local medium is, heated, enriched and shaped by multiple recent explosions.

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BibTeXRIS

I. A. Grenier. 2000-11-15. Gamma-ray sources as relics of recent supernovae in the nearby Gould Belt. https://arxiv.org/abs/astro-ph/0011298

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