Spiral arms and the angular momentum gap in Milky Way Cepheids
| العنوان: | Spiral arms and the angular momentum gap in Milky Way Cepheids |
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| المؤلفون: | Marcin Semczuk, Walter Dehnen, Ralph Schönrich, E Athanassoula |
| المساهمون: | University of Leicester, University College of London [London] (UCL) |
| المصدر: | Monthly Notices of the Royal Astronomical Society Monthly Notices of the Royal Astronomical Society, 2023, 519, pp.902-908. ⟨10.1093/mnras/stac3528⟩ |
| بيانات النشر: | Oxford University Press (OUP), 2022. |
| سنة النشر: | 2022 |
| مصطلحات موضوعية: | galaxies: spiral, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Galaxy: disc, FOS: Physical sciences, Astronomy and Astrophysics, Galaxy: kinematics and dynamics, Galaxy: structure, Astrophysics - Astrophysics of Galaxies, stars: variables: Cepheids |
| الوصف: | The angular-momentum distribution of classical Cepheids in the outer Milky Way disc is bi-modal with a gap at $L_\mathrm{gap}=2950\,\mathrm{km}\,\mathrm{s}^{-1}\,\mathrm{kpc}$, corresponding to $R=13\,\mathrm{kpc}$, while no similar feature has been found in the general population of disc stars. We show that star formation in multiple spiral arm segments at the same azimuth leads to such multi-modality which quickly dissolves and only shows in young stars. Unlike other explanations, such as a 1:1 orbital resonance with the Galactic bar, this also accounts for the observed steepening of the stellar warp at $L_\mathrm{gap}$, since the adjacent spiral arms represent different parts of the warped gas disc. In this scenario the gap is clearly present only in young stars, as observed, while most purely stellar dynamical origins would affect all disc populations, including older disc stars. 6 pages, 7 figures, submitted to MNRAS |
| تدمد: | 1365-2966 0035-8711 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::47aec5ef861b0965dcbaef2ccd15a3e5 https://doi.org/10.1093/mnras/stac3528 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....47aec5ef861b0965dcbaef2ccd15a3e5 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 13652966 00358711 |
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