arXiv subjects

I. Kostyukov

Publications and source records attributed to I. Kostyukov.

8 recordsLinked to original sources

arXiv2013

Electron acceleration by coherent laser pulse echelons in periodic plasma structures

We consider a possibilty to use an echelon of mutually coherent laser pulses generated by the emerging CAN (Coherent Amplification Network) technology for direct particle acceleration in periodic plasma structures. The plasma structure survives a single shot only. However, due to it's simplicity and projected very low production costs, the structure can be replaced for every laser shot at a kiloherz repetition rate. We discuss resonant and free streaming configurations. The resonant plasma structures can trap energy of longer laser pulses but are limited to moderate laser intensities of about 10^{14}\,{\rm W/cm^{2}} and are very sensitive to the structure quality. The free streaming configurations can survive laser intensities above 10^{18}\,{\rm W/cm^{2}} for several tens of femtoseconds so that sustained accelerating rates well above {\rm TeV/m} are feasible. In our full electromagnetic relativistic particle-in-cell (PIC) simulations we show a test electron bunch gaining up to 120\,{\rm GeV} over a distance of 5.3\,{\rm cm} only.

physics.plasm-ph↗

arXiv2009

Electron Self-injection in Multidimensional Relativistic Plasma Wakefields

We present an analytical model for electron self-injection in nonlinear, multidimensional plasma wave excited by short laser pulse in the bubble regime or by short electron beam in the blowout regime. In this regimes, which are typical for electron acceleration in the last experiments, the laser radiation pressure or the electron beam charge pushes out background plasma electrons forming a plasma cavity - bubble - with a huge ion charge. The plasma electrons can be trapped in the bubble and accelerated by the plasma wakefields up to very high energies. The model predicts the condition for electron trapping and the trapping cross section in terms of the bubble radius and the bubble velocity. The obtained results are in a good agreement with results of 3D PIC simulations.

physics.plasm-ph↗

arXiv2007

Control of laser wake field acceleration by plasma density profile

We show that both the maximum energy gain and the accelerated beam quality can be efficiently controlled by the plasma density profile. Choosing a proper density gradient one can uplift the dephasing limitation. When a periodic wake field is exploited, the phase synchronism between the bunch of relativistic particles and the plasma wave can be maintained over extended distances due to the plasma density gradient. Putting electrons into the $n-$th wake period behind the driving laser pulse, the maximum energy gain is increased by the factor $2πn$ over that in the case of uniform plasma. The acceleration is limited then by laser depletion rather than by dephasing. Further, we show that the natural energy spread of the particle bunch acquired at the acceleration stage can be effectively removed by a matched deceleration stage, where a larger plasma density is used.

physics.plasm-ph↗

arXiv2007

Radiative Losses in Plasma Accelerators

We investigate the dynamics of a relativistic electron in a strongly nonlinear plasma wave in terms of classical mechanics by taking into account the action of the radiative reaction force. The two limiting cases are considered. In the first case where the energy of the accelerated electrons is low, the electron makes many betatron oscillations during the acceleration. In the second case where the energy of the accelerated electrons is high, the betatron oscillation period is longer than the electron residence time in the accelerating phase. We show that the force of radiative friction can severely limit the rate of electron acceleration in a plasma accelerator.

physics.acc-ph↗

arXiv2006

Radiation Emission by Extreme Relativistic Electrons and Pair Production by Hard Photons in a Strong Plasma Wakefield

Radiation spectrum of extreme relativistic electrons and a probability of electron-positron pair production by energetic photons in a strong plasma wakefield are derived in the framework of a semiclassical approach. It is shown that that the radiation losses of the relativistic electron in the plasma wakefield scale as $ \propto ε^{2 / 3}$ in the quantum limit when the energy of the radiated photon becomes close to the electron energy, $ε$. The quantum effects will play a key role in future plasma-based accelerators operating at ultrahigh energy of the electrons.

physics.plasm-ph↗

arXiv2004

The Bubble regime of laser-plasma acceleration: monoenergetic electrons and the scalability

The Bubble regime of electron acceleration in ultra-relativistic laser plasma is considered. It has been shown that the bubble can produce ultra-short dense bunches of electrons with quasi-monoenergetic energy spectra. The first experiment in this regime done at LOA has confirmed the peaked electron spectrum (J. Faure, et al., {\it submitted}, 2004). The generated electron bunch may have density an order of magnitude higher than that of the background plasma. The bubble is able to guide the laser pulse over many Rayleigh lengths, thus no preformed plasma channel is needed for high-energy particle acceleration in the bubble regime. In the present work we discuss a simple analytical model for the bubble fields as well as the scaling laws.

physics.plasm-ph↗

arXiv2004

Table-top synchrotron

Using three-dimensional particle-in-cell simulations we show that a strongly nonlinear plasma wave excited by an ultrahigh intensity laser pulse works as a compact high-brightness source of X-ray radiation. It has been recently suggested by A. Pukhov and J. Meyer-ter-Vehn, Appl. Phys. B \textbf{74}, 355 (2002), that in a strongly nonlinear regime the plasma wave transforms to a ``bubble'', which is almost free from background electrons. Inside the bubble, a dense bunch of relativistic electrons is produced. These accelerated electrons make betatron oscillations in the transverse fields of the bubble and emit a bright broadband X-ray radiation with a maximum about 50 keV. The emission is confined to a small angle of about 0.1 rad. In addition, we make simulations of X-ray generation by an external 28.5-GeV electron bunch injected into the bubble. $γ$-quanta with up to GeV energies are observed in the simulation in a good agreement with analytical results. The energy conversion is efficient, leading to a significant stopping of the electron bunch over 5 mm interaction distance.

physics.optics↗

arXiv2003

Spontaneous and Stimulated Synchrotron Radiation from Relativistic Electrons in Ion Channel

Spontaneous and stimulated emission of an electron in the ion channel is studied. The emission processes are studied in the regime of high harmonic generation when the parameter of plasma wiggler strength is large. Like for conventional free electron laser, a synchrotron-like broadband spectrum is generated in this regime. The asymptotic expression for the radiation spectrum of the spontaneous emission is derived. The radiation spectrum emitted from axisymmetric monoenergetic electron beam is analyzed. The gain of ion-channel synchrotron-radiation laser is calculated. Use of laser-produced ion channel for efficient X-ray generation is discussed.

physics.optics↗