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arXiv · 2009.13575

Discovery of a Fast Expanding Shell in the Inside-out Born-Again Planetary Nebula HuBi 1 Through High-Dispersion Integral Field Spectroscopy

J. S. Rechy-García·M. A. Guerrero·E. Santamaría·V. M. A. Gómez-González·G. Ramos-Larios·J. A. Toalá·S. Cazzoli·L. Sabin·L. F. Miranda·X. Fang·J. Liu
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Abstract

HuBi 1 has been proposed to be member of the rare class of born-again planetary nebulae (PNe), i.e., its central star experienced a very late thermal pulse and ejected highly-processed material at high speeds inside the old hydrogen-rich PN. In this letter we present GTC MEGARA integral field spectroscopic observations of the innermost regions of HuBi 1 at high spectral resolution $\simeq16$ km s$^{-1}$ and multi-epoch sub-arcsec images obtained $\simeq 12$ yr apart. The analysis of these data indicates that the inner regions of HuBi 1 were ejected $\simeq200$ yr ago and expand at velocities $\simeq300$ km s$^{-1}$, in excellent agreement with the born-again scenario. The unprecedented tomographic capabilities of the GTC MEGARA high-dispersion observations used here reveal that the ejecta in HuBi 1 has a shell-like structure, in contrast to the disrupted disk and jet morphology of the ejecta in other born-again PNe.

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J. S. Rechy-García, M. A. Guerrero, E. Santamaría, V. M. A. Gómez-González, G. Ramos-Larios, J. A. Toalá, S. Cazzoli, L. Sabin, L. F. Miranda, X. Fang, J. Liu. 2020-09-28. Discovery of a Fast Expanding Shell in the Inside-out Born-Again Planetary Nebula HuBi 1 Through High-Dispersion Integral Field Spectroscopy. https://doi.org/10.3847/2041-8213%2Fabbe22

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