TY - JOUR
T1 - Electron-ion-ion coincidence experiments for photofragmentation of polyatomic molecules using pulsed electric fields
T2 - Treatment of random coincidences
AU - Prümper, G.
AU - Ueda, K.
N1 - Funding Information:
The measurements were carried out with the approval of the SPring-8 program review committee and were supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science. The authors are grateful to the staff of SPring-8 for their help in the course of these studies.
PY - 2007/5/1
Y1 - 2007/5/1
N2 - In molecular photofragmentation processes by soft X-rays, a number of ionic fragments can be produced, each having a different abundance and correlation with the kinetic energy of the emitted electron. For investigating these fragmentation processes, electron-ion and electron-ion-ion coincidence experiments, in which the kinetic energy of electrons are analyzed using an electrostatic analyzer while the mass of the ions is analyzed using a pulsed electric field, are very powerful. For such measurements, however, the contribution of random coincidences is substantial and affects the data in a non-trivial way. Simple intuitive subtraction methods cannot be applied. In the present paper, we describe these electron-ion and electron-ion-ion coincidence experiments together with a subtraction method for the contribution from random coincidences. We provide a comprehensive set of equations for the data treatment, including equations for the calculation of error-bars. We demonstrate the method by applying it to the fragmentation of free CF3 SF5 molecules.
AB - In molecular photofragmentation processes by soft X-rays, a number of ionic fragments can be produced, each having a different abundance and correlation with the kinetic energy of the emitted electron. For investigating these fragmentation processes, electron-ion and electron-ion-ion coincidence experiments, in which the kinetic energy of electrons are analyzed using an electrostatic analyzer while the mass of the ions is analyzed using a pulsed electric field, are very powerful. For such measurements, however, the contribution of random coincidences is substantial and affects the data in a non-trivial way. Simple intuitive subtraction methods cannot be applied. In the present paper, we describe these electron-ion and electron-ion-ion coincidence experiments together with a subtraction method for the contribution from random coincidences. We provide a comprehensive set of equations for the data treatment, including equations for the calculation of error-bars. We demonstrate the method by applying it to the fragmentation of free CF3 SF5 molecules.
KW - Algorithm
KW - Coincidence
KW - PEPIPICO
KW - Random coincidence
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U2 - 10.1016/j.nima.2007.02.071
DO - 10.1016/j.nima.2007.02.071
M3 - Article
AN - SCOPUS:34047114943
VL - 574
SP - 350
EP - 362
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
SN - 0168-9002
IS - 2
ER -