41 citations · 116 across the 11 of their papers we have counts for
11 papers
Photoexcitation spectroscopy of highly charged ions for application to astronomy using a compact electron beam ion trap (EBIT) at the synchrotron radiation facility SPring-8
Leo Hirata, Yuki Amano, Moto Togawa +6
In the past few decades, X-ray astronomy satellites equipped with grating spectrometers and microcalorimeters have enabled high-resolution spectroscopic observations of astrophysic…
A laboratory plasma experiment for X-ray astronomy using a compact electron beam ion trap (EBIT)
Yuki Amano, Leo Hirata, Moto Togawa +11
We present the basic performance and experimental results of an electron beam ion trap (JAXA-EBIT), newly introduced to the Japanese astronomical community. Accurate atomic data ar…
Enhanced One-Color-Two-Photon Resonant Ionization in Highly Charged Ions by Fine-Structure Effects
Moto Togawa, Chunhai Lyu, Chintan Shah +25
Ultraintense pulses from X-ray free-electron lasers can drive, within femtoseconds, multiple processes in the inner shells of atoms and molecules in all phases of matter. The ensui…
Hanle Effect for Lifetime Analysis: Li-like Ions
Jan Richter, Moto Togawa, José R. Crespo López-Urrutia +1
Accurate lifetime measurements of excited states of highly charged ions (HCIs) are essential for advancing diagnostics in both laboratory and astrophysical plasmas, especially in t…
Hanle effect for lifetime determinations in the soft X-ray regime
Moto Togawa, Jan Richter, Chintan Shah +16
By exciting a series of transitions in helium-like nitrogen ions with linearly polarized mono…
High-accuracy Measurements of Core-excited Transitions in Light Li-like Ions
Moto Togawa, Steffen Kühn, Chintan Shah +11
The transition energies of the two -core-excited soft X-ray lines (dubbed q and r) from to the respective upper levels an…
Natural-linewidth measurements of the 3C and 3D soft-x-ray transitions in Ni XIX
Chintan Shah, Steffen Kühn, Sonja Bernitt +15
We used the monochromatic soft-x-ray beamline P04 at the synchrotron-radiation facility PETRA III to resonantly excite the strongest transitions in neon-like Ni XIX ions, $…
High-Precision Transition Energy Measurements of Neon-like Fe XVII Ions
Chintan Shah, Moto Togawa, Marc Botz +15
We improve by a factor of 4-20 the energy accuracy of the strongest soft X-ray transitions of Fe XVII ions by resonantly exciting them in an electron beam ion trap with a monochrom…
New Measurement Resolves Key Astrophysical Fe XVII Oscillator Strength Problem
Steffen Kühn, Charles Cheung, Natalia S. Oreshkina +19
One of the most enduring and intensively studied problems of X-ray astronomy is the disagreement of state-of-the art theory and observations for the intensity ratio of two Fe XVII…
Observation of strong two-electron--one-photon transitions in few-electron ion
Moto Togawa, Steffen Kühn, Chintan Shah +22
We resonantly excite the series of O and O up to principal quantum number with monochromatic x rays, producing -shell holes, and observe their relaxatio…
High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
Steffen Kühn, Chintan Shah, José R. Crespo López-Urrutia +29
For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic transitions, and , in Fe XVII ions found oscillator…