Near L-Edge Single and Multiple Photoionization of Doubly Charged Iron Ions

التفاصيل البيبلوغرافية
العنوان: Near L-Edge Single and Multiple Photoionization of Doubly Charged Iron Ions
المؤلفون: Schippers, Stefan, Beerwerth, Randolf, Bari, Sadia, Buhr, Ticia, Holste, Kristof, Kilcoyne, A. L. David, Perry-Sassmannshausen, Alexander, Phaneuf, Ronald A., Reinwardt, Simon, Savin, Daniel Wolf, Schubert, Kaja, Fritzsche, Stephan, Martins, Michael, Müller, Alfred
المصدر: Astrophys. J. 908 (2021) 52
سنة النشر: 2020
المجموعة: Astrophysics
Physics (Other)
مصطلحات موضوعية: Physics - Atomic Physics, Astrophysics - Instrumentation and Methods for Astrophysics
الوصف: Using the photon-ion merged-beams technique at a synchrotron light source, we have measured relative cross sections for single and up to five-fold photoionization of Fe$^{2+}$ ions in the energy range 690--920 eV. This range contains thresholds and resonances associated with ionization and excitation of $2p$ and $2s$ electrons. Calculations were performed to simulate the total absorption spectra. The theoretical results show very good agreement with the experimental data, if overall energy shifts of up to 2.5 eV are applied to the calculated resonance positions and assumptions are made about the initial experimental population of the various levels of the Fe$^{2+}$([Ar]$3d^6$) ground configuration. Furthermore, we performed extensive calculations of the Auger cascades that result when an electron is removed from the $2p$ subshell of Fe$^{2+}$. These computations lead to a better agreement with the measured product-charge-state distributions as compared to earlier work. We conclude that the $L$-shell absorption features of low-charged iron ions are useful for identifying gas-phase iron in the interstellar medium and for discriminating against the various forms of condensed-phase iron bound to composite interstellar dust grains.
Comment: 11 pages, 7 figures, 1 table
نوع الوثيقة: Working Paper
DOI: 10.3847/1538-4357/abcc64
URL الوصول: http://arxiv.org/abs/2010.00473
رقم الانضمام: edsarx.2010.00473
قاعدة البيانات: arXiv
الوصف
DOI:10.3847/1538-4357/abcc64