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arXiv · 1109.4658

Gamma-Ray Observations of the Supernova Remnant RX J0852.0-4622 with the Fermi LAT

T. Tanaka·A. Allafort·J. Ballet·S. Funk·F. Giordano·J. Hewitt·M. Lemoine-Goumard·H. Tajima·O. Tibolla·Y. Uchiyama
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Abstract

We report on gamma-ray observations of the supernova remnant (SNR) RX J0852.0-4622 with the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope. In the Fermi LAT data, we find a spatially extended source at the location of the SNR. The extension is consistent with the SNR size seen in other wavelengths such as X-rays and TeV gamma rays, leading to the identification of the gamma-ray source with the SNR. The spectrum is well described as a power law with a photon index of Gamma = 1.85 +/- 0.06 (stat) (+0.18,-0.19) (sys), which smoothly connects to the H.E.S.S. spectrum in the TeV energy band. We discuss the gamma-ray emission mechanism based on multiwavelength data. The broadband data can be fit well by a model in which the gamma rays are of hadronic origin. We also consider a scenario with inverse Compton scattering of electrons as the emission mechanism of the gamma rays. Although the leptonic model predicts a harder spectrum in the Fermi LAT energy range, the model can fit the data considering the statistical and systematic errors.

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T. Tanaka, A. Allafort, J. Ballet, S. Funk, F. Giordano, J. Hewitt, M. Lemoine-Goumard, H. Tajima, O. Tibolla, Y. Uchiyama. 2011-09-21. Gamma-Ray Observations of the Supernova Remnant RX J0852.0-4622 with the Fermi LAT. https://doi.org/10.1088/2041-8205%2F740%2F2%2Fl51

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