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In this work we present support for recent claims that advocate a downward revision of the solar oxygen abundance. Our analysis employs spatially-resolved spectro-polarimetric observations including the FeI lines at 6302 AA and the OI infrared triplet around 7774 AA in the quiet Sun. We used the FeI lines to reconstruct the three-dimensional thermal and magnetic structure of the atmosphere. The simultaneous OI observations were then employed to determine the abundance of oxygen at each pixel, using both LTE and non-LTE (NLTE) approaches to the radiative transfer. In this manner, we obtain values of lgEO=8.63 (NLTE) and 8.93 (LTE) dex. We find an unsettling fluctuation of the oxygen abundance over the field of view. This is likely an artifact indicating that, even with this relatively refined strategy, important physical ingredients are still missing in the picture. By examining the spatial distribution of the abundance, we estimate realistic confidence limits of approximately 0.1 dex.
Higher order moments of net conserved charge fluctuations, in particular net baryon number and net electric charge, are sensitive thermodynamic observables that respond strongly to critical behavior in strong interaction matter. In order to use them
Terrestrial planets with large water inventories are likely ubiquitous and will be among the first Earth-sized planets to be characterized with upcoming telescopes. It has previously been argued that waterworlds-particularly those possessing more tha
In online debates individual arguments support or attack each other, leading to some subset of arguments being considered more relevant than others. However, in large discussions readers are often forced to sample a subset of the arguments being put
Motivated by the controversy over the surface metallicity of the Sun, we present a re-analysis of the solar photospheric oxygen (O) abundance. New atomic models of O and Ni are used to perform Non-Local Thermodynamic Equilibrium (NLTE) calculations w
The so-called textit{China crisis}, well documented in textit{History of the IAU} by Adriaan Blaauw and in textit{Under the Same Starry Sky: History of the IAU} by Chengqi Fu and Shuhua Ye, refers to the withdrawal in 1960 of the Peoples Republic of