The soft X-ray and XUV split-and-delay unit at beamlines FL23/24 at FLASH2.
J Synchrotron Radiat
; 30(Pt 2): 479-489, 2023 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-36891862
ABSTRACT
A split-and-delay unit for the extreme ultraviolet and soft X-ray spectral regions has been built which enables time-resolved experiments at beamlines FL23 and FL24 at the Free-electron LASer in Hamburg (FLASH). Geometric wavefront splitting at a sharp edge of a beam splitting mirror is applied to split the incoming soft X-ray pulse into two beams. Ni and Pt coatings at grazing incidence angles have been chosen in order to cover the whole spectral range of FLASH2 and beyond, up to hν = 1800â
eV. In the variable beam path with a grazing incidence angle of Ïd = 1.8°, the total transmission (T) ranges are of the order of 0.48 < T < 0.84 for hν < 100â
eV and T > 0.50 for 100â
eV < hν < 650â
eV with the Ni coating, and T > 0.06 for hν < 1800â
eV for the Pt coating. For a fixed beam path with a grazing incidence angle of Ïf = 1.3°, a transmission of T > 0.61 with the Ni coating and T > 0.23 with a Pt coating is achieved. Soft X-ray pump/soft X-ray probe experiments are possible within a delay range of -5â
ps < Δt < +18â
ps with a nominal time resolution of tr = 66â
as and a measured timing jitter of tj = 121 ± 2â
as. First experiments with the split-and-delay unit determined the averaged coherence time of FLASH2 to be τc = 1.75â
fs at λ = 8â
nm, measured at a purposely reduced coherence of the free-electron laser.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Synchrotron Radiat
Assunto da revista:
RADIOLOGIA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Alemanha