Abstract We show a new resonance acceleration scheme for generating ultradense relativistic electron bunches in helical motions and hence emitting brilliant vortical γ -ray pulses the quantum electrodynamic (QED) regime of circularly-polarized (CP) laser-plasma interactions. Here combined effects radiation reaction recoil force self-generated magnetic fields result not only trapping great amount electrons laser-produced plasma channel, but also significant broadening bandwidth between laser...

A method to achieve stable radiation pressure acceleration (RPA) of heavy ions from laser-irradiated ultrathin foils is proposed, where a high-Z material coating in front used. The coated material, acting as moving electron repository, continuously replenishes the accelerating ion foil with comoving electrons light-sail stage due its successive ionization under laser fields Gaussian temporal profile. As result, detrimental effects such deformation and loss induced by Rayleigh-Taylor-like...

A scheme for enhanced quantum electrodynamics (QED) production of electron-positron-pair plasmas is proposed that uses two ultraintense lasers irradiating a thin solid foil from opposite sides. In the scheme, under proper matching condition, in addition to skin-depth emission $\ensuremath{\gamma}$-ray photons and Breit-Wheeler creation pairs on each side foil, large number high-energy electrons one can propagate through it interact with laser other side, leading much pair production. More...

Ultraintense laser absorption and γ-ray synchrotron radiation in near-critical-density (NCD) plasmas are investigated. Besides the known skin-depth emission reinjected electron NCD plasmas, we find a new mechanism, where γ-rays dominantly produced by Transversely Oscillating Electron Emission (TOEE). In this TOEE electrons mainly oscillate transverse direction under balance between longitudinal ponderomotive force restoring electrostatic force. A great amount of γ photons emitted direction,...

The dynamics of magnetic reconnection (MR) in the high-energy-density (HED) regime, where plasma inflow is strongly driven and thermal pressure larger than $(\ensuremath{\beta}>1)$, reexamined theoretically by particle-in-cell simulations. Interactions two colliding laser-produced bubbles with self-generated poloidal fields of, respectively, antiparallel parallel field lines are considered. Through comparison, it found that quadrupole field, bipolar electric heating, even out-of-plane can...

A method to maintain ion stable radiation pressure acceleration (RPA) from laser-irradiated thin foils is proposed, where a series of high-Z nanofilms are placed behind successively replenish co-moving electrons into the accelerating foil as electron charging stations (ECSs). Such replenishment electrons, on one hand, helps keep dynamic balance between electrostatic in slab and increasing laser with Gaussian temporal profile at rising front, i.e. dynamically matching optimal condition RPA;...

Electron acceleration and γ-ray emission by circularly polarized laser pulses interacting with near-critical-density plasmas are systematically investigated for both the non-quantum-electrodynamic (non-QED) QED regimes. In non-QED regime, since electron density in plasma channel is small self-generated electromagnetic fields weak, only a few electrons can achieve resonant acceleration, leading to weak emission. However, when it comes radiation recoil force significantly affects dynamics,...

A practical approach to achieve strong coherent synchrotron emissions (CSE) in relativistic laser-plasma interaction is proposed, where a plane target with its electron density satisfying the self-similar parameter S≃ne0/a0nc=1 obliquely irradiated by P-polarized laser pulse. In this case, electrons at surface are periodically dragged out into vacuum field component perpendicular surface, resulting formation of series dense bunches propagating along surface. Intense CSE generated these under...

Coherent synchrotron emission (CSE) from relativistic near-critical-density (NCD) plasmas irradiated by a few-cycle laser pulse is investigated theoretically and numerically. Due to the unique larger laser-plasma interaction region in NCD plasmas, compared those solid targets, not only required stringent conditions for CSE on target are relaxed but also radiation intensities enhanced two orders of magnitude. Moreover, it found that single attosecond can be easily obtained transmitted...

A scheme for identifying the quantum radiation reaction effect on relativistic electron motion in strong electromagnetic fields is proposed, where two ultraintense lasers are used to collide with each other a tenuous gas. Different from previous method by collision of an laser high-energy beam, which evidenced energy loss spectrum, here transition between classical and regimes distinguished angular distribution total radiations. With no need additional beams, more robust easily achievable...

An advanced target for production of high-energy monoenergetic ion beams by intense laser pulses is proposed, in which the near-critical plasma transversely confined between high-Z dense wires. It found that acceleration significantly enhanced due to strong magnetic dipole vortex formed at rear target, where large electron current density gradients from wires vacuum exist. The helps realize contraction momentum phase spaces and reduction beam divergence so monenergetic, highly directed,...

Generation of intense single attosecond pulses from coherent synchrotron emission (CSE), in the transmitted direction laser-irradiated double foil targets, has been investigated theoretically and numerically. Unlike conventional CSE target case, here dense electron nanobunch is formed vacuum gap between two foils, which composed electrons blown out first ultrathin foil. Owing to existence gap, can be accelerated more energy. In addition, laser energy penetrate through get reflected second...

Magnetic reconnection (MR) in the high-energy-density (HED) regime is comprehensively investigated by particle-in-cell simulations. In HED regime, MR process driven two colliding magnetized plasma bubbles produced intense lasers, where there are ambiguities distinguishing actual consequences from pure bubble squeezing effects, because both lead to similar behaviors. After discerning these similarities, such as two-fluid heating and jetting, we establish direct relevance between of with...

As an efficient mechanism of energy release, magnetic reconnection is popular to explain many explosive events in extreme environments. In some cases, however, we show the key concept X and O points ambiguous, due its non-covariant definition. A simple model constructed study case when point disturbed by in-plane electric field. The dynamics charged particle investigated near point, where there a localized attractive or repulsive potential. We find that orbits particles are chaotic, which...

We find that the transport of relativistic flows in extreme magnetic fields can be achieved a relay manner by considering quantum electromagnetic cascade process, where photons play key role as medium. During transport, flow emits particle energy into via synchrotron radiation, and then gains particles back pair creation, forming “particle-photon-particle” relay. Particle-in-cell simulations demonstrate forward density is realized self-replenishment process with photon-pair cascades, while...

The composition of the astrophysical relativistic jets remains uncertain. By kinetic particle-in-cell simulations, we show that baryon component in jet, or so-called loading effect (BLE), heavily affects transport dynamics interstellar medium. On one hand, with BLE, can a much longer distance, because jet electrons draw significant amount energy from baryons via Buneman-induced electrostatic waves and Weibel-mediated collisionless shock; on other electron phase space distribution may...

The gas ratio of aging process during CRT manufacturing was studied to clarify the influence residual gases on cathode characteristics. According experimental results, by proper controlling ratio, damage or contamination can be avoided. In addition, using electron beam simulation software trajectory quantitatively realized and an optimum parameter achieved.