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تسجيل مستخدم جديدThe Progenitors and Lifetimes of Planetary Nebula
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Planetary Nebulae (PNe) are amongst the most spectacular objects produced by stellar evolution, but the exact identity of their progenitors has never been established for a large and homogeneous observational sample. We investigate the relationship between PNe and their stellar progenitors in the Large Magellanic Cloud (LMC) through the statistical comparison between a highly complete spectroscopic catalog of PNe and the spatially resolved age distribution of the underlying stellar populations. We find that most PN progenitors in the LMC have main-sequence lifetimes in a narrow range between 5 and 8 Gyr, which corresponds to masses between 1.2 and 1.0 M$_{odot}$, and produce PNe that last $26^{+6}_{-7}$~kyr on average. We tentatively detect a second population of PN progenitors, with main-sequence lifetimes between 35 and 800~Myr, i.e., masses between 8.2 and 2.1 M$_{odot}$, and average PN lifetimes of $11^{+6}_{-7}$ kyr. These two distinct and disjoint populations of progenitors strongly suggest the existence of at least two physically distinct formation channels for PNe. Our determination of PN lifetimes and progenitor masses has implications for the understanding of PNe in the context of stellar evolution models, and for the role that rotation, magnetic fields, and binarity can play in the shaping of PN morphologies.
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