Crossed beam photodissociation imaging of HeH+ with vacuum ultraviolet free-electron laser pulses.
Molecular photofragmentation has been studied by event imaging on HeH+ ions at 32 nm (38.7 eV) in a fast ion beam crossed with the free-electron laser in Hamburg (FLASH), analyzing neutral He product directions and energies. Fragmentation into He(1snl,n > or = 2)+H+ was observed to yield significant photodissociation at 32 nm with an absolute cross section of (1.4+/-0.7) x 10(-18) cm2, releasing energies of 10-20 eV. A clear dominance of photodissociation perpendicular to the laser polarization was found in contrast to the excitation paths so far emphasized in theoretical studies.
Pedersen
H B
HB
Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany. hendrik.pedersen@mpi-hd.mpg.de
Altevogt
S
S
Jordon-Thaden
B
B
Heber
O
O
Rappaport
M L
ML
Schwalm
D
D
Ullrich
J
J
Zajfman
D
D
Treusch
R
R
Guerassimova
N
N
Martins
M
M
Hoeft
J-T
JT
Wellhöfer
M
M
Wolf
A
A