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Even if the title of Wolfgang Koeppen's last novel, "Der Tod in Rom", alludes quite obviously to Thomas Mann's novella, "Der Tod in Venedig", Koeppen's text must be understood first and foremost as a response to Mann's most controversial novel, "Doktor Faustus". The novels of Mann and Koeppen rank among the most well-known literary examinations of National Socialism but stand in a complementary relation to each other. "Doktor Faustus", published in 1947, analyses the cultural and intellectual origins of German fascism, while "Der Tod in Rom", published only seven years later in 1954, criticizes the continuity of National Socialist ideologies in post-war Germany. Both authors focus their analyses of fascism on fictional avant-garde composers who seem at first glance detached from any political context. [...] The actual starting point of Florian Trabert's paper, however, is the fact that both novels are preceded by epigraphs taken from Dante's "Inferno". Trabert begins by commenting on the references to Dante in "Doktor Faustus" and then continues by analysing the allusions to the "Commedia" in Koeppen's novel, which constitute, as Trabert demonstrates, a complex constellation among the three texts.
How long does it take to emit an electron from an atom? This question has intrigued scientists for decades. As such emission times are in the attosecond regime, the advent of attosecond metrology using ultrashort and intense lasers has re-triggered strong interest on the topic from an experimental standpoint. Here, we present an approach to measure such emission delays, which does not require attosecond light pulses, and works without the presence of superimposed infrared laser fields. We instead extract the emission delay from the interference pattern generated as the emitted photoelectron is diffracted by the parent ion’s potential. Targeting core electrons in CO, we measured a 2d map of photoelectron emission delays in the molecular frame over a wide range of electron energies. The emission times depend drastically on the photoelectrons’ emission directions in the molecular frame and exhibit characteristic changes along the shape resonance of the molecule.
A central motivation for the development of x-ray free-electron lasers has been the prospect of time-resolved single-molecule imaging with atomic resolution. Here, we show that x-ray photoelectron diffraction—where a photoelectron emitted after x-ray absorption illuminates the molecular structure from within—can be used to image the increase of the internuclear distance during the x-ray-induced fragmentation of an O2 molecule. By measuring the molecular-frame photoelectron emission patterns for a two-photon sequential K-shell ionization in coincidence with the fragment ions, and by sorting the data as a function of the measured kinetic energy release, we can resolve the elongation of the molecular bond by approximately 1.2 a.u. within the duration of the x-ray pulse. The experiment paves the road toward time-resolved pump-probe photoelectron diffraction imaging at high-repetition-rate x-ray free-electron lasers.