Particle transport within the pulsar wind nebula HESS J1825-137
We present a detailed view of the pulsar wind nebula (PWN) HESS J1825-137. We aim to constrain the mechanisms dominating the particle transport within the nebula, accounting for its anomalously large size and spectral characteristics.<i>Aims.<i/> The nebula was studied using a deep expos...
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| Main Authors: | , , , , , , |
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| Corporate Author: | |
| Format: | Article (Journal) |
| Language: | English |
| Published: |
15 January 2019
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| In: |
Astronomy and astrophysics
Year: 2019, Volume: 621 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201834335 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1051/0004-6361/201834335 Verlag, Volltext: https:/articles/aa/abs/2019/01/aa34335-18/aa34335-18.html 
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| Author Notes: | H. Abdalla, D. Glawion, F. Jankowsky, M. Mohamed, A. Quirrenbach, S. Schwemmer, S.J. Wagner [und weitere] |
| Summary: | We present a detailed view of the pulsar wind nebula (PWN) HESS J1825-137. We aim to constrain the mechanisms dominating the particle transport within the nebula, accounting for its anomalously large size and spectral characteristics.<i>Aims.<i/> The nebula was studied using a deep exposure from over 12 years of H.E.S.S. I operation, together with data from H.E.S.S. II that improve the low-energy sensitivity. Enhanced energy-dependent morphological and spatially resolved spectral analyses probe the very high energy (VHE, E > 0.1 TeV) <i>γ<i/>-ray properties of the nebula.<i>Methods.<i/> The nebula emission is revealed to extend out to 1.5° from the pulsar, ~1.5 times farther than previously seen, making HESS J1825-137, with an intrinsic diameter of ~100 pc, potentially the largest <i>γ<i/>-ray PWN currently known. Characterising the strongly energy-dependent morphology of the nebula enables us to constrain the particle transport mechanisms. A dependence of the nebula extent with energy of <i>R<i/> ∝ <i>E<i/><sup><i>α<i/><sup/> with <i>α<i/> = −0.29 ± 0.04<sub>stat<sub/> ± 0.05<sub>sys<sub/> disfavours a pure diffusion scenario for particle transport within the nebula. The total <i>γ<i/>-ray flux of the nebula above 1 TeV is found to be (1.12 ± 0.03<sub>stat<sub/> ± 0.25<sub>sys<sub/>) × 10<sup>−11<sup/> cm<sup>−2<sup/> s<sup>−1<sup/>, corresponding to ~64% of the flux of the Crab nebula.<i>Results.<i/> HESS J1825-137 is a PWN with clearly energy-dependent morphology at VHE <i>γ<i/>-ray energies. This source is used as a laboratory to investigate particle transport within intermediate-age PWNe. Based on deep observations of this highly spatially extended PWN, we produce a spectral map of the region that provides insights into the spectral variation within the nebula. |
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| Item Description: | Gesehen am 19.08.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201834335 |