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Related papers: Space-charge effects in the field-assisted thermio…

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Tracking capabilities in Time Projection Chambers (TPCs) are strongly dictated by the homogeneity of the drift field. Ion back-flow in various gas detectors, mainly induced by the secondary ionization processes during amplification, has…

An approximate analytic solution is constructed for the 2-d space charge limited emission by a cathode surrounded by non emitting conducting ledges of width Lambda. An essentially exact solution (via conformal mapping) of the electrostatic…

Plasma Physics · Physics 2009-11-10 A. Rokhlenko , Joel L. Lebowitz

In this work, the thermionic cooling effect during thermionic discharges with parallel plate electrodes at 1 Torr is investigated. Time-resolved observation of electron emission and surface temperature is realized in addition to the typical…

Plasma Physics · Physics 2024-03-11 Junhwi Bak , Albina Tropina , James Creel , Richard B. Miles

It has been empirically observed in both experiments and particle-in-cell simulations that space-charge-dominated beams suffer strong growth in statistical phase-space area (degraded quality) and particle losses in alternating gradient…

Accelerator Physics · Physics 2009-11-11 Steven M. Lund , Sugreev R. Chawla

We investigate the finite temperature fermionic condensate and the expectation values of the charge and current densities for a massive fermion field in a spacetime background with an arbitrary number of toroidally compactified spatial…

High Energy Physics - Theory · Physics 2014-04-23 S. Bellucci , E. R. Bezerra de Mello , A. A. Saharian

The influence of the space charge of ions emitted from the surface of a conical spike on its shape has been studied. The problem of the calculation of the spatial distributions of the electric field, ion velocity field, and the space charge…

Classical Physics · Physics 2012-01-19 Grey Sh. Boltachev , Nikolay M. Zubarev , Olga V. Zubareva

Space charge effects can be very important for the dynamics of intense particle beams, as they repeatedly pass through nonlinear focusing elements, aiming to maximize the beam's luminosity properties in the storage rings of a high energy…

Accelerator Physics · Physics 2008-11-26 T. Bountis , Ch. Skokos

The introduction of the surface plasmon polarizations makes the emittance of the photocathode complicated. In this paper, the emittance of plasmon-enhanced photocathode is analyzed. It is first demonstrated that the plasmonic near field can…

Accelerator Physics · Physics 2016-07-08 Zeng-gong Jiang , Qiang Gu , Xu-dong Li , Meng Zhang , Duan Gu

Molecular dynamics simulations, with full Coulomb interaction and self-consistent field emission, are used to examine mutual space-charge interactions between beams originating from several emitter areas, in a planar infinite diode. The…

Computational Physics · Physics 2022-06-15 Hakon Valur Haraldsson , Kristinn Torfason , Andrei Manolescu , Agust Valfells

In electron cooling, the space charge (SC) is an important effect, which will affect the e-beam velocity distribution and thus the cooling performance. In this paper, we analyse several important effects that due to the space charge field,…

Accelerator Physics · Physics 2024-02-29 He Zhao

Un-gated thermionic cathode RF guns are well known as a robust source of electrons for many accelerator applications. These sources are in principle scalable to high currents without degradation of the transverse emittance due to control…

Accelerator Physics · Physics 2017-05-04 J. P. Edelen , J. R. Harris

The current-voltage characteristic of a planar vacuum diode with electrons possessing velocity distribution function during an emission from the cathode (electron beam) is theoretically considered in this article. The electron beam movement…

General Physics · Physics 2008-05-14 Dimitar G. Stoyanov

The initial modulation in the scheme for Coherent electron Cooling (CeC) rests on the screening of the ion charge by electrons. However, in a CeC system with a bunched electron beam, inevitably, a long-range longitudinal space charge force…

Accelerator Physics · Physics 2015-06-19 Gang Wang , Michael Blaskiewicz , V. N. Litvinenko

In a current density versus temperature (J-T) (Miram) curve in thermionic electron emission, experimental measurements demonstrate there is a smooth transition between the exponential region and the saturated emission regions, which is…

Applied Physics · Physics 2023-03-22 Dongzheng Chen , Ryan Jacobs , Dane Morgan , John Booske

We simulate numerically the classical charge dynamics in a microscopic, planar, vacuum diode with a finite emitter area and a finite number of electrons in the gap. We assume electrons are emitted under space-charge limited conditions with…

Accelerator Physics · Physics 2020-12-15 Johannes Bergur Gunnarsson , Kristinn Torfason , Andrei Manolescu , Agust Valfells

The electron beam dynamics in a nonmagnetized high-current vacuum diode is analyzed for different cathode-anode gap geometries. The conditions enabling to achieve the minimal {initial} momentum spread in the electron beam are found out. A…

Plasma Physics · Physics 2016-08-16 Sergey Anishchenko , Alexandra Gurinovich

The present letter extends the prior findings on self-induced heating of solid state field emission devices. It was found that a vacuum diode (base pressure $\sim10^{-9}$ Torr), that makes use of graphite-rich polycrystalline diamond as…

Materials Science · Physics 2019-06-20 Stanislav S. Baturin , Tanvi Nikhar , Sergey V. Baryshev

A device has been built and tested, in which a ceramic superconducting cathode and a copper anode cause electrical discharges in low pressure gases, at temperatures between 50 and 70 K. The electrodes are connected to a capacitors array…

General Physics · Physics 2007-05-23 Evgeny Podkletnov , Giovanni Modanese

Electron transpiration cooling (ETC) can reduce aerothermal loads on sharp hypersonic leading edges, but its performance is governed by whether thermionically emitted electrons escape the hot surface or return as cathode-directed backflow.…

Plasma Physics · Physics 2026-05-11 Wushun Zhang , Weixing Zhou , Yinjian Zhao

The space-charge-limited current in a zero thickness planar thin film depends on the geometry of the electrodes. We present a theory which is to a large extent analytical and applicable to many different lay-outs. We show that a…

Classical Physics · Physics 2016-09-28 Patrick De Visschere