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arXiv · 2409.13640

Evidence of a Forming Nucleus in the Fourcade-Figueroa Galaxy

Horacio Dottori·Ruben J. Diaz
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Abstract

We analyze data from the IRAS, WISE, and Planck satellites, revealing an unresolved dust condensation at the center of the Fourcade-Figueroa galaxy (ESO270-G017), which may correspond to a forming nucleus. We model the condensation's continuum spectrum in the spectral range from 3 to 1300 microns using the DUSTY code. The best-fit model, based on the Chi-square test, indicates that the condensation is a shell with an outer temperature of T_out ~ 12 K and an inner boundary temperature of T_i ~ 500 K. The shell's outer radius is r_o = 86.2 pc, and the inner cavity radius is r_i = 0.082 pc. The condensation produces an extinction A_V = 50 mag and its luminosity is L_c = 1.08E34 W, which would correspond to a burst of massive star formation approximately similar to the central 5 pc of R136 in the LMC and NGC3603, the ionizing cluster of a giant Carina arm HII region. The comparison with Normal, Luminous, and Ultra-Luminous Infrared Galaxies leads us to consider this obscured nucleus as the nearest and weakest object of this category.

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Horacio Dottori, Ruben J. Diaz. 2024-09-20. Evidence of a Forming Nucleus in the Fourcade-Figueroa Galaxy. https://arxiv.org/abs/2409.13640

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