Effect of aerosol concentration on post-corona unipolar diffusion charging: ion density retro-controlled by aerosol space charge versus geometry of ion-aerosol mixing

Electron-beam propagation from a gas-filled diode is investigated. The beginning portion of the electron beam pulse creates an ion channel not only inside the diode but also in the region beyond the anode. A theoretical model is developed for the space-charge-limited current of a relativistic electron beam propagating through an ion channel. A simple analytical expression for the space-charge-limited current is obtained within the context of a thin-beam approximation, where the conducting-tube radius is much larger than the beam radius. The beam current propagating through an ion channel is measured experimentally for a mildly relativistic electron beam. Whenever the ion density inside the diode is the same as the beam electron density, the diode is short-circuited. The ion-channel density at the short-circuiting time is calculated numerically and is used to estimate the space-charge-limited current. It is shown that the experimental data agree well with the analytical results predicted by the theoretical model.

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Space Charge Effect in Spectrometers of Ion Mobility Increment with a Cylindrical Drift Chamber

European Journal of Mass Spectrometry ◽

10.1255/ejms.881 ◽

2007 ◽

Vol 13 (4) ◽

pp. 259-272 ◽

Cited By ~ 3

Author(s):

A.A. Elistratov ◽

L.A. Sherbakov

Keyword(s):

Space Charge ◽

Ion Mobility ◽

Drift Chamber ◽

Space Charge Effect ◽

Single Type ◽

Charge Effect ◽

Ion Density ◽

Focusing Effect ◽

High Frequency Electric Field ◽

Order Of Magnitude

We have amplified the model for the drift of ions under a non-uniform, high-frequency electric field by taking space charge effect into account. By this means, we have investigated the effect of space charge on the dynamics of a single type of ions in a spectrometer of ion mobility increment with a cylindrical drift chamber. The counteraction of the space charge effect and the focusing effect is investigated. The output ion current saturation caused by the effect of the space charge is observed. The shape of the ion peak, taking into consideration the space charge effect, has been obtained. We show that the effect of the space charge is sufficient for the relative ion density greater than 10 ppt by order of magnitude (for a cylindrical geometry spectrometer with typical parameters).

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Ion density limitation in a Penning trap due to the combined effect of asymmetry and space charge

Applied Physics B Photophysics and Laser Chemistry ◽

10.1007/bf00694417 ◽

1989 ◽

Vol 48 (1) ◽

pp. 51-54 ◽

Cited By ~ 19

Author(s):

J. Yu ◽

M. Desaintfuscien ◽

F. Plumelle

Keyword(s):

Space Charge ◽

Penning Trap ◽

Combined Effect ◽

Ion Density

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ESTIMATION OF SPACE CHARGE INFLUENCE ON RESOLUTION OF ION-MOBILITY SPECTROMETER

NAUCHNOE PRIBOROSTROENIE ◽

10.18358/np-31-4-i4154 ◽

2021 ◽

Vol 31 (4) ◽

pp. 41-54

Author(s):

I. V. Kurnin ◽

Keyword(s):

Space Charge ◽

Numerical Solution ◽

Analytical Model ◽

Ion Mobility ◽

Ion Density ◽

Ion Mobility Spectrometer ◽

Reaction Region ◽

Ion Cloud ◽

Comparison Of The Results

The paper presents an analytical model describing the dynamics of ion cloud, taking into account the action of space charge during a motion in ion mobility spectrometer — starting from the reaction region, where the shutter forms an ion pulse, and the further drift of the formed ion pulse towards the collector. The presented model lets to estimate the degree of influence of the space charge on possible ion losses and the resolution of ion mobility spectrometer. The effect of the space charge becomes noticeable, starting with the ion density of 106 cm–3. Comparison of the results obtained using the analytical model with the results of numerical solution of the initial equations shows that they practically coincide.

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Electron holography of interfaces in electroceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151271 ◽

1993 ◽

Vol 51 ◽

pp. 1088-1089

Author(s):

Vinayak P. Dravid ◽

V. Ravikumar ◽

Richard Plass

Keyword(s):

Space Charge ◽

Direct Evidence ◽

Materials Science ◽

Theoretical Work ◽

Electron Holography ◽

Resolution Limit ◽

Interference Phenomenon ◽

X Ray ◽

Electron Sources ◽

Science Community

With the advent of coherent electron sources with cold field emission guns (cFEGs), it has become possible to utilize the coherent interference phenomenon and perform “practical” electron holography. Historically, holography was envisioned to extent the resolution limit by compensating coherent aberrations. Indeed such work has been done with reasonable success in a few laboratories around the world. However, it is the ability of electron holography to map electrical and magnetic fields which has caught considerable attention of materials science community.There has been considerable theoretical work on formation of space charge on surfaces and internal interfaces. In particular, formation and nature of space charge have important implications for the performance of numerous electroceramics which derive their useful properties from electrically active grain boundaries. Bonnell and coworkers, in their elegant STM experiments provided the direct evidence for GB space charge and its sign, while Chiang et al. used the indirect but powerful technique of x-ray microchemical profiling across GBs to infer the nature of space charge.

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