Near-ultraviolet luminescence of N2 irradiated by short X-ray pulses.
The Linac Coherent Light Source is an x-ray free-electron laser that recently demonstrated lasing in the 1.5-15 Å wavelength range. We report on luminescence measurements of a molecular nitrogen gas irradiated by ∼2  mJ, 80 fs x-ray pulses at energies of 0.83, 2.7, and 8.3 keV. These results provide a direct test of our current understanding of photoabsorption, electron dynamics, and fluorescence processes for such intense, ultrashort x-ray pulses. At 0.83 keV, the duration of the fluorescence signal depends strongly on space-charge effects. At 8.3 keV, space-charge effects are weak, and the signal duration is determined by the Auger electron dynamics.
Hau-Riege
Stefan P
SP
Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
Bionta
Richard M
RM
Ryutov
Dmitri D
DD
London
Richard A
RA
Ables
Elden
E
Kishiyama
Keith I
KI
Shen
Stewart
S
McKernan
Mark A
MA
McMahon
Donn H
DH
Messerschmidt
Marc
M
Krzywinski
Jacek
J
Stefan
Peter
P
Turner
James
J
Ziaja
Beata
B