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arXiv · 1612.02250

Detection of diffuse gamma-ray emission near the young massive cluster NGC 3603

Rui-zhi Yang·Felix Aharonian
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Abstract

We report the Fermi Large Area Telescope's detection of extended gamma-ray emission towards the direction of the young massive star cluster NGC 3603. The emission shows a hard spectrum with a photon index of 2.3 from 1 GeV to 250 GeV. The large size and high luminosity of this structure make it unlikely a pulsar wind nebular. On the other hand the spatial correlation with the ionised gas indicate a hadronic origin. The total cosmic ray (CR) protons energy are estimated to be of the order $10^{50} ~\rm erg$ assuming the gamma-ray are produced in the interaction of CRs with ambient gas . The environment and spectral features show significant similarity with the Cygnus cocoon. It reveals that the young star clusters may be a gamma-ray source population and they can potentially accelerate a significant fraction of the Galactic cosmic rays.

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Rui-zhi Yang, Felix Aharonian. 2016-12-07. Detection of diffuse gamma-ray emission near the young massive cluster NGC 3603. https://doi.org/10.1051/0004-6361%2F201630213

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