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The SED of the TeV BLLac 1ES 1426+428 after correction for the TeV--IR absorption

L. Costamante·F. Aharonian·G. Ghisellini·D. Horns
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Abstract

The recent HEGRA detection and spectrum of 1ES 1426+428 at TeV energies, once corrected for absorption using present estimates of the diffuse extragalactic IR background, suggest that the high energy peak of the Spectral Energy Distribution (SED) could be much higher than the synchrotron one ($L_c/L_s>10$), and lie at energies above 8-10 TeV. To see if such an SED could be accounted for, we have applied a "finite injection time" SSC model, and present here some preliminary results. Within this model, we found the need of an external ("ambient") contribution to the energy density of seed photons, in order to account for both the high Compton dominance and the hard spectrum.

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L. Costamante, F. Aharonian, G. Ghisellini, D. Horns. 2003-01-13. The SED of the TeV BLLac 1ES 1426+428 after correction for the TeV--IR absorption. https://doi.org/10.1016/s1387-6473(03)00121-0

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