ATI as a source for multiply charged ion production in a laser field
نویسنده
چکیده
A theory for the many-electron multi-photon process is presented. It is shown that after single-electron excitation into some level in the continuum (ATI) an inelastic collision of the excited electron with the parent atomic particle can result in an excitation of the ion. It may be the continuum state excitation giving the doubly charged ion or the discrete state which also greatly enhances the doubly charged ion production. The probability of these phenomena greatly exceeds that of the direct ionization of a single-charged ion. The single-electron ATI makes possible the two-electron process even in the moderate field. The example of two-electron excitations of He atom in a 780 nm laser field with intensity above ≈ 10 14 W/cm 2 is discussed.
منابع مشابه
Adiabatic mechanism of the multiply charged ion production by a laser field through ATI states of an atom
ATI can be followed by an inelastic collision of the ionized electron with the parent atomic particle resulting in an excitation of the ion. It may be a continuum state excitation producing the doubly charged ion or a discrete state which also enhances the doubly charged ion production. Absorption of a few quanta above the atomic threshold is sufficient to make this mechanism work. As a result ...
متن کاملInvestigation and optimization of parameters affecting the multiply charged ion yield in AP-MALDI MS.
Liquid matrix-assisted laser desorption/ionization (MALDI) allows the generation of predominantly multiply charged ions in atmospheric pressure (AP) MALDI ion sources for mass spectrometry (MS) analysis. The charge state distribution of the generated ions and the efficiency of the ion source in generating such ions crucially depend on the desolvation regime of the MALDI plume after desorption i...
متن کاملA Low Power Low Cost 2.45 Ghz Ecris for the Production of Multiply Charged Ions
A low cost, low power ECR ion source designed for the use on a high voltage platform with limited electrical power available, has been developed. To reduce the power consumption of the source the radial and axial magnetic confinement are produced entirely by permanent magnets. An axial magnetic mirror ratio of 2.7 is obtained by a configuration of two times four block magnets. A radial magnetic...
متن کاملElectrospray ionization high-resolution ion mobility spectrometry-mass spectrometry.
A hybrid atmospheric pressure ion mobility spectrometer is described which exhibits resolving power approaching the diffusion limit for singly and multiply charged ions (over 200 for the most favorable case). Using an electrospray ionization source and a downstream quadrupole mass spectrometer with electron multiplier as detector, this ESI-IMS-MS instrument demonstrates the potential of IMS for...
متن کاملLiquid AP-UV-MALDI Enables Stable Ion Yields of Multiply Charged Peptide and Protein Ions for Sensitive Analysis by Mass Spectrometry**
In biological mass spectrometry (MS), two ionization techniques are predominantly employed for the analysis of larger biomolecules, such as polypeptides. These are nano-electrospray ionization (nanoESI) and matrix-assisted laser desorption/ionization (MALDI). Both techniques are considered to be “soft”, allowing the desorption and ionization of intact molecular analyte species and thus their su...
متن کامل