A Way Out of the Bubble Trouble?—Upon Reconstructing the Origin of the Local Bubble and Loop I via Radioisotopic Signatures on Earth
| Autor: | Jenny Feige, Dieter Breitschwerdt, Michael Mathias Schulreich, C. Dettbarn |
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| Rok vydání: | 2018 |
| Předmět: |
lcsh:Astronomy
Astrophysics::High Energy Astrophysical Phenomena Bubble FOS: Physical sciences Superbubble Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences ISM: abundances methods: numerical methods: analytical lcsh:QB1-991 0103 physical sciences 010306 general physics 010303 astronomy & astrophysics Stellar evolution Astrophysics::Galaxy Astrophysics ISM: supernova remnants High Energy Astrophysical Phenomena (astro-ph.HE) Physics Astronomy and Astrophysics Astrophysics - Astrophysics of Galaxies Loop (topology) Interstellar medium Supernova Local Bubble Astrophysics of Galaxies (astro-ph.GA) Extraterrestrial life hydrodynamics ddc:520 Astrophysics - High Energy Astrophysical Phenomena ISM: bubbles |
| Zdroj: | Galaxies, Vol 6, Iss 1, p 26 (2018) |
| ISSN: | 2075-4434 |
| DOI: | 10.3390/galaxies6010026 |
| Popis: | Deep-sea archives all over the world show an enhanced concentration of the radionuclide $^{60}$Fe, isolated in layers dating from about 2.2 Myr ago. Since this comparatively long-lived isotope is not naturally produced on Earth, such an enhancement can only be attributed to extraterrestrial sources, particularly one or several nearby supernovae in the recent past. It has been speculated that these supernovae might have been involved in the formation of the Local Superbubble, our Galactic habitat. Here, we summarize our efforts in giving a quantitative evidence for this scenario. Besides analytical calculations, we present results from high-resolution hydrodynamical simulations of the Local Superbubble and its presumptive neighbor Loop I in different environments, including a self-consistently evolved supernova-driven interstellar medium. For the superbubble modeling, the time sequence and locations of the generating core-collapse supernova explosions are taken into account, which are derived from the mass spectrum of the perished members of certain, carefully preselected stellar moving groups. The release and turbulent mixing of $^{60}$Fe is followed via passive scalars, where the yields of the decaying radioisotope were adjusted according to recent stellar evolution calculations. The models are able to reproduce both the timing and the intensity of the $^{60}$Fe excess observed with rather high precision. We close with a discussion of recent developments and give future perspectives. 10 pages, 3 figures, published in the special issue of Galaxies: "Searching for Connections among the Fermi Bubbles, the Galactic Center GeV Excess, and Loop I" |
| Databáze: | OpenAIRE |
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