_version_ 1866913491079659520
author Kühn, Steffen
Shah, Chintan
López-Urrutia, José R. Crespo
Fujii, Keisuke
Steinbrügge, René
Stierhof, Jakob
Togawa, Moto
Harman, Zoltán
Oreshkina, Natalia S.
Cheung, Charles
Kozlov, Mikhail G.
Porsev, Sergey G.
Safronova, Marianna S.
Berengut, Julian C.
Rosner, Michael
Bissinger, Matthias
Ballhausen, Ralf
Hell, Natalie
Park, SungNam
Chung, Moses
Hoesch, Moritz
Seltmann, Jörn
Surzhykov, Andrey S.
Yerokhin, Vladimir A.
Wilms, Jörn
Porter, F. Scott
Stöhlker, Thomas
Keitel, Christoph H.
Pfeifer, Thomas
Brown, Gregory V.
Leutenegger, Maurice A.
Bernitt, Sven
author_facet Kühn, Steffen
Shah, Chintan
López-Urrutia, José R. Crespo
Fujii, Keisuke
Steinbrügge, René
Stierhof, Jakob
Togawa, Moto
Harman, Zoltán
Oreshkina, Natalia S.
Cheung, Charles
Kozlov, Mikhail G.
Porsev, Sergey G.
Safronova, Marianna S.
Berengut, Julian C.
Rosner, Michael
Bissinger, Matthias
Ballhausen, Ralf
Hell, Natalie
Park, SungNam
Chung, Moses
Hoesch, Moritz
Seltmann, Jörn
Surzhykov, Andrey S.
Yerokhin, Vladimir A.
Wilms, Jörn
Porter, F. Scott
Stöhlker, Thomas
Keitel, Christoph H.
Pfeifer, Thomas
Brown, Gregory V.
Leutenegger, Maurice A.
Bernitt, Sven
contents For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic $2p-3d$ transitions, $3C$ and $3D$, in Fe XVII ions found oscillator strength ratios $f(3C)/f(3D)$ disagreeing with theory, but uncertainties had precluded definitive statements on this much studied conundrum. Here, we resonantly excite these lines using synchrotron radiation at PETRA III, and reach, at a millionfold lower photon intensities, a 10 times higher spectral resolution, and 3 times smaller uncertainty than earlier work. Our final result of $f(3C)/f(3D) = 3.09(8)(6)$ supports many of the earlier clean astrophysical and laboratory observations, while departing by five sigmas from our own newest large-scale ab initio calculations, and excluding all proposed explanations, including those invoking nonlinear effects and population transfers.
format Preprint
id arxiv_https___arxiv_org_abs_1911_09707
institution arXiv
publishDate 2019
record_format arxiv
spellingShingle High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
Kühn, Steffen
Shah, Chintan
López-Urrutia, José R. Crespo
Fujii, Keisuke
Steinbrügge, René
Stierhof, Jakob
Togawa, Moto
Harman, Zoltán
Oreshkina, Natalia S.
Cheung, Charles
Kozlov, Mikhail G.
Porsev, Sergey G.
Safronova, Marianna S.
Berengut, Julian C.
Rosner, Michael
Bissinger, Matthias
Ballhausen, Ralf
Hell, Natalie
Park, SungNam
Chung, Moses
Hoesch, Moritz
Seltmann, Jörn
Surzhykov, Andrey S.
Yerokhin, Vladimir A.
Wilms, Jörn
Porter, F. Scott
Stöhlker, Thomas
Keitel, Christoph H.
Pfeifer, Thomas
Brown, Gregory V.
Leutenegger, Maurice A.
Bernitt, Sven
Atomic Physics
High Energy Astrophysical Phenomena
Instrumentation and Methods for Astrophysics
Solar and Stellar Astrophysics
Plasma Physics
For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic $2p-3d$ transitions, $3C$ and $3D$, in Fe XVII ions found oscillator strength ratios $f(3C)/f(3D)$ disagreeing with theory, but uncertainties had precluded definitive statements on this much studied conundrum. Here, we resonantly excite these lines using synchrotron radiation at PETRA III, and reach, at a millionfold lower photon intensities, a 10 times higher spectral resolution, and 3 times smaller uncertainty than earlier work. Our final result of $f(3C)/f(3D) = 3.09(8)(6)$ supports many of the earlier clean astrophysical and laboratory observations, while departing by five sigmas from our own newest large-scale ab initio calculations, and excluding all proposed explanations, including those invoking nonlinear effects and population transfers.
title High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
topic Atomic Physics
High Energy Astrophysical Phenomena
Instrumentation and Methods for Astrophysics
Solar and Stellar Astrophysics
Plasma Physics
url https://arxiv.org/abs/1911.09707