| 1. |
- Sanchez-Gonzalez, A., et al.
(författare)
-
Auger electron and photoabsorption spectra of glycine in the vicinity of the oxygen K-edge measured with an X-FEL
- 2015
-
Ingår i: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:23
-
Tidskriftsartikel (refereegranskat)abstract
- We report the first measurement of the near oxygen K-edge auger spectrum of the glycine molecule. Our work employed an x-ray free electron laser as the photon source operated with input photon energies tunable between 527 and 547 eV. Complete electron spectra were recorded at each photon energy in the tuning range, revealing resonant and non-resonant auger structures. Finally ab initio theoretical predictions are compared with the measured above the edge auger spectrum and an assignment of auger decay channels is performed.
|
|
| 2. |
- Zhaunerchyk, Vitali, et al.
(författare)
-
Disentangling formation of multiple-core holes in aminophenol molecules exposed to bright X-FEL radiation
- 2015
-
Ingår i: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:24
-
Tidskriftsartikel (refereegranskat)abstract
- Competing multi-photon ionization processes, some leading to the formation of double core hole states, have been examined in 4-aminophenol. The experiments used the linac coherent light source (LCLS) x-ray free electron laser, in combination with a time-of-flight magnetic bottle electron spectrometer and the correlation analysis method of covariance mapping. The results imply that 4-aminophenol molecules exposed to the focused x-ray pulses of the LCLS sequentially absorb more than two x-ray photons, resulting in the formation of multiple core holes as well as in the sequential removal of photoelectrons and Auger electrons (so-called PAPA sequences).
|
|
| 3. |
- Mucke, Melanie, et al.
(författare)
-
Covariance mapping of two-photon double core hole states in C2H2 and C2H6 produced by an x-ray free electron laser
- 2015
-
Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 17
-
Tidskriftsartikel (refereegranskat)abstract
- Few-photon ionization and relaxation processes in acetylene (C2H2) and ethane (C2H6) were investigated at the linac coherent light source x-ray free electron laser (FEL) at SLAC, Stanford using a highly efficient multi-particle correlation spectroscopy technique based on a magnetic bottle. The analysis method of covariance mapping has been applied and enhanced, allowing us to identify electron pairs associated with double core hole (DCH) production and competing multiple ionization processes including Auger decay sequences. The experimental technique and the analysis procedure are discussed in the light of earlier investigations of DCH studies carried out at the same FEL and at third generation synchrotron radiation sources. In particular, we demonstrate the capability of the covariance mapping technique to disentangle the formation of molecular DCH states which is barely feasible with conventional electron spectroscopy methods.
|
|
| 4. |
- Andersson, Jonas, et al.
(författare)
-
Triple ionization of atomic Cd involving 4p(-1) and 4s(-1) inner-shell holes
- 2015
-
Ingår i: Physical Review A. - 1050-2947 .- 1094-1622. ; 92:2
-
Tidskriftsartikel (refereegranskat)abstract
- The triple ionization spectrum of atomic Cd formed upon the removal of a 4p or a 4s inner-shell electron and subsequent Auger decays has been obtained at 200 eV photon energy. By using a versatile multielectron coincidence detection technique based on a magnetic bottle spectrometer in combination with multiconfiguration Dirac-Fock calculations, Auger cascades leading to tricationic final states have been analyzed and final-state configurations have been identified. The most prominent Auger cascades leading to the ground state of Cd3+ have been identified in good agreement with theory.
|
|
| 5. |
- Eland, John H. D., 1941, et al.
(författare)
-
Direct observation of three-electron collective decay in a resonant Auger process
- 2015
-
Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 17
-
Tidskriftsartikel (refereegranskat)abstract
- Using a multi-electron coincidence technique combined with synchrotron radiation we demonstrate the real existence of the elusive three-electron collective process in resonant Auger decay of Kr. The three-electron process is about 40 times weaker than the competing two-electron processes.
|
|
| 6. |
- Eland, John H. D., 1941, et al.
(författare)
-
Ion charge-resolved branching in decay of inner shell holes in Xe up to 1200eV
- 2015
-
Ingår i: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:20
-
Tidskriftsartikel (refereegranskat)abstract
- Using a new multi-electron multi-ion coincidence apparatus and soft x-ray synchrotron radiation we have determined branching ratios to final Xen+ states with 2 < n < 9 from the 4d(-1), 4p(-1), 4s(-1), 3d(-1) and 3p(-1) Xe+ hole states. The coincident electron spectra give information on the Auger cascade pathways. We show that by judicious choice of coincident electrons, almost pure single charge states of the final ions can be selected.
|
|
