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Today's research on the cathodic arc deposition technique and coatings therefrom primarily focuses on the effects of, e.g., nitrogen partial pressure, growth temperature, and substrate bias. Detailed studies on the morphology and structure of the starting material--the cathode--during film growth and its influence on coating properties at different process conditions are rare. This work aims to study the evolution of the converted layer, its morphology, and microstructure, as a function of the cathode material grain size during deposition of Ti-Al-N coatings. The coatings were reactively grown in pure N2 discharges from powder metallurgically manufactured Ti-50 at.% Al cathodes with grain size distribution averages close to 1800, 100, 50, and 10 µm, respectively, and characterized with respect to microstructure, composition, and mechanical properties. The results indicate that for the cathode of 1800 µm grain size the disparity in the work function among parent phases plays a dominant role in the pronounced erosion of Al, which yields the coatings rich in macro-particles and of high Al content. We further observed that a reduction in the grain size of Ti-50 at.% Al cathodes to 10 µm provides favorable conditions for self-sustaining reactions between Ti and Al phases upon arcing to form c phase. The combination of self-sustaining reaction and the arc process not only result in the formation of hole-like and sub-hole features on the converted layer but also generate coatings of high Al content and laden with macro-particles. [ABSTRACT FROM AUTHOR]

Rate constants at room temperature (293 ± 2 K) and atmospheric pressure for the reaction of methyl n-propyl ether (MnPE), CH3OCH2CH2CH3, with OH and NO3 radicals and the Cl atom have been determined in a 100 L FEP-Teflon reaction chamber in conjunction with gas chromatography-flame ionization detector (GC-FID) as the detection technique. The obtained rate constants k (in units of cm³ molecule-1 s-1) are (9.91 ± 2.30) x 10-12, (1.67 ± 0.32) x 10-15, and (2.52 ± 0.14) x 10-10 for reactions with OH, NO3, and Cl, respectively. The products of these reactions were investigated by gas chromatography-mass spectrometry (GC-MS), and formation mechanisms are proposed for the observed reaction products. Atmospheric lifetimes of the studied ether, calculated from rate constants of the different reactions, reveal that the dominant loss process for MnPE is its reaction with OH, while in coastal areas and in the marine boundary layer, MnPE loss by Cl reaction is also important. [ABSTRACT FROM AUTHOR]

We present a numerical model of plasma formation in ultrafast laser ablation on the dielectrics surface. Ablation threshold dependence on pulse duration is predicted with the model and the numerical results for water agrees well with the experimental data for pulse duration from 140 fs to 10 ps. Influences of parameters and approximations of photo- and avalanche-ionization on the ablation threshold prediction are analyzed in detail for various pulse lengths. The calculated ablation threshold is strongly dependent on electron collision time for all the pulse durations. The complete photoionization model is preferred for pulses shorter than 1 ps rather than the multiphoton ionization approximations. The transition time of inverse bremsstrahlung absorption needs to be considered when pulses are shorter than 5 ps and it can also ensure the avalanche ionization (AI) coefficient consistent with that in multiple rate equations (MREs) for pulses shorter than 300 fs. The threshold electron density for AI is only crucial for longer pulses. It is reasonable to ignore the recombination loss for pulses shorter than 100 fs. In addition to thermal transport and hydrodynamics, neglecting the threshold density for AI and recombination could also contribute to the disagreements between the numerical and the experimental results for longer pulses. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizer supply and use play a vital role in determining crop growth and yield. However, the effects of nitrogen fertilizer levels on plant growth under waterlogging conditions remain elusive. The objective of this study was to investigate the effects of nitrogen fertilizer rates (0, 90, 180, 270, and 360 kg N ha-1, designated N0, N1, N2, N3, and N4, respectively) on leaf physiological characteristics and grain yield of maize (Zea mays L.) under two water regimes (WW or well-watered through the maize grown season and WL or waterlogged for six days at the sixth-leaf stage). Overall, in comparison to WW, WL treatment showed a reduction in the following traits, at all nitrogen rates: plant height, leaf area index, SPAD value, superoxide dismutase, peroxidase, and catalase activity, net photosynthetic rate (Pn), transpiration rate, stomatal conductance, ears per ha, kernels per ear, 1,000-kernel weight, and grain yield. Moreover, the majority of the above parameters increased with the increase in nitrogen application rate under WL, as a result of the enhanced available nitrogen content at higher nitrogen application rates. Therefore, increasing supply levels of nitrogen fertilizer could improve antioxidant enzyme activity and Pn, consequently producing increased maize grain yield under waterlogged conditions. [ABSTRACT FROM AUTHOR]

The impact of global climate change has led to an increase in extreme rainfall events, causing fluctuations in terrigenic inputs that significantly affect aquatic communities. Lake Changhu, the third-largest freshwater lake in Hubei Province, plays a crucial role as a reservoir of aquatic germplasm resources in the middle reaches of the Yangtze River. In recent years, the lake has experienced a series of extreme rainfall events. In response to recent extreme rainfall events, a 42-day mesocosm experiment was conducted to understand the effect of terrigenic inputs on various aspects of phytoplankton in Lake Changhu, such as species composition, abundance, biomass, diversity, community turnover rates, resource use efficiency, and stability. The experiment involved the application of different terrigenic treatments, including a control group (CK, using lake water), low terrigenic input (LT), medium terrigenic input (MT), and high terrigenic input (HT). The results showed a noticeable shift in phytoplankton composition from a co-dominated state of Chlorophyta and Cyanobacteria in the CK treatment to a Cyanobacteria-dominated state in the other terrigenic treatments. Furthermore, the terrigenic inputs increased phytoplankton abundance, community turnover rates, diversity, and resistance. Comparatively, the diversity index of phytoplankton increased by 82.61%, 73.83%, and 70.41% in the LT, MT, and HT treatments, respectively, in contrast to the CK treatment. However, phytoplankton abundance decreased by 6.99%, 15.55%, and 14.76% in the LT, MT, and HT treatments. Additionally, the resource use efficiency decreased by 1.94%, 5.16%, and 14.19% in the LT, MT, and HT treatments, respectively, compared to the CK treatment. These findings provide valuable insights into monitoring and managing the water ecology in Lake Changhu, offering a scientific basis for implementing effective management strategies. [ABSTRACT FROM AUTHOR]

Allyl acetate (AA) is widely used as monomer and intermediate in industrial chemicals synthesis. To evaluate the atmospheric outcome of AA, kinetics and mechanism of its gas-phase reaction with main atmospheric oxidants (O3, OH, Cl, and NO3) have been investigated in a Teflon reactor at 298 ± 3 K. Both absolute and relative rate methods were used to determine the rate constants for AA reactions with the four atmospheric oxidants. The obtained rate constants (in units of cm³ molecule-1 s-1) are (1.8 ± 0.3) x 10-18, (3.1 ± 0.7) x 10-11, (2.5 ± 0.5) x 10-10, and (1.1 ± 0.4) x 10-14, for reactions with O3, OH, Cl, and NO3, respectively. While results for reactions with O3, OH and Cl are in good agreement with previous studies, the kinetics for the reaction with NO3 is reported for the first time in this study. On the basis of determined rate constants, the tropospheric lifetimes of AA are τO3 = 9 days, τOH = 5 h, τCl = 5 days, τNO3 = 2 days. On the basis of the products study, reaction mechanisms for these oxidations have been proposed and the reaction products were detected using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and Fourier transform infrared spectroscopy (FTIR). Results show that the main products formed in these reactions are carbonyl compounds. In particular, 2-oxoethyl acetate was detected in all four AA oxidation reactions. Compared to previous studies, several new products were determined for reactions with OH and Cl. These results form a set of comprehensive kinetic data for AA reactions with main atmospheric oxidants and provide a better understanding of the degradation and atmospheric outcome of unsaturated acetate esters in the troposphere, during both daytime and nighttime. [ABSTRACT FROM AUTHOR]

Organophosphate flame retardants (OPFRs), as alternatives of polybrominated diphenyl ethers (PBDEs), have been frequently detected in the environment and biota, and could pose adverse effects on organisms. However, information on the potential endocrine disruption of OPFRs, especially their effects on steroid hormone receptors, such as glucocorticoid and mineralocorticoid receptors (GR/MR), is limited. In this study, the dual-luciferase reporter gene assay via GR/MR and a H295R steroidogenesis assay were employed to evaluate the endocrine disruption of nine OPFRs. We found TMPP, TPHP, and TDBPP exhibited both GR and MR antagonistic activities, while TNBP and TDCIPP only showed MR antagonistic property within a concentration range of 10-8 to 10-5 mol/L(M). In the H295R steroidogenesis assay, the fold changes of eight steroidogenic genes in response to OPFRs were further studied. We found CYP17,CYP21, and CYP11B1 expression were significantly down-regulated following TMPP, TPHP, or TDBPP exposure at a concentration of 2 x 10-6 M. Meanwhile TMPP decreased the production of cortisol and TDBPP down-regulated the secretion of aldosterone. Our results indicate that some OPFRs can interact with GR and MR, and have the potential to disturb steroidogenesis. Data provided here will be helpful to comprehensively understand the potential endocrine disruption of OPFRs. [ABSTRACT FROM AUTHOR]

Laser-accelerated electrons are promising in producing gamma-photon beams of high peak flux for the study of nuclear photonics, obtaining copious positrons and exploring photon--photon interaction in vacuum. We report on the experimental generation of brilliant gamma-ray beams with not only high photon yield but also low divergence, based on picosecond laser-accelerated electrons. The 120 J 1 ps laser pulse drives self-modulated wakefield acceleration in a high-density gas jet and generates tens-of-MeV electrons with 26 nC and divergence as small as 1.51°. These collimated electrons produce gamma-ray photons through bremsstrahlung radiation when transversing a high-Z solid target. We design a high-energy-resolution Compton-scattering spectrometer and find that a total photon number of 2.2x109 is captured within an acceptance angle of 1.1° for photon energies up to 16 MeV. Comparison between the experimental results and Monte Carlo simulations illustrates that the photon beam inherits the small divergence from electrons, corresponding to a total photon number of 2.2x1011 and a divergence of 7.73°. [ABSTRACT FROM AUTHOR]

As optical parametric chirped pulse amplification has been widely adopted for the generation of extreme intensity laser sources, nonlinear crystals of large aperture are demanded for high-energy amplifiers. Yttrium calcium oxyborate (YCa4O(BO3)3, YCOB) is capable of being grown with apertures exceeding 100 mm, which makes it possible for application in systems of petawatt scale. In this paper, we experimentally demonstrated for the first time to our knowledge, an ultra-broadband non-collinear optical parametric amplifier with YCOB for petawatt-scale compressed pulse generation at 800 nm. Based on the SG-II 5 PWfacility, amplified signal energy of approximately 40 J was achieved and pump-to-signal conversion efficiency was up to 42.3%. A gain bandwidth of 87 nm was realized and supported a compressed pulse duration of 22.3 fs. The near-field and wavefront aberration represented excellent characteristics, which were comparable with those achieved in lithium triborate-based amplifiers. These results verified the great potential for YCOB utilization in the future. [ABSTRACT FROM AUTHOR]

A new squaraine dye Bis(4- N, N-dicarboxymethyl-2-hydroxyphenyl)squaraine (SQ) which could be used as organic photovoltaic materials, was synthesized, and its molecular structure was fully characterized by elemental analysis, IR, 1H NMR and MS. SQ exhibits strong absorption band over 600–700 nm. Addition of TiO2 colloids to the ethanol solution of SQ resulted in the increase of optical density, quenching of fluorescence and shortened fluorescence lifetime. The apparent association constant between the sensitizer and semiconductor as measured from the fluorescence quenching data, was 2427 M−1. Fluorescence lifetime measurements gave the rate constant for the electron injection process from the excited singlet of SQ to the conduction band of TiO2 nanoparticles as 2.55 × 10 8 s−1. In addition, SQ doped SiO2 gel glass slices were prepared and characterized by absorption and emission spectra. [ABSTRACT FROM AUTHOR]

Although it is a simple and convenient birefringence analysis instrument, the traditional planar polariscope is difficult to use for the quantitative measurement of phase retardation and azimuth angle. A novel 2D quantitative birefringence measurement method based on ptychographic iterative engine (PIE) in a planar polariscope is proposed. The birefringent sample is placed in the parallel probe-forming path. By inserting an isotropic diffractive object with good modulation property for the probe, the ptychographic scan measurements are performed under two different dark-field states. The amplitudes and phases of the two probes containing different birefringence information were reconstructed, and the phase retardation and azimuth angle obtained with a simple and straightforward extraction approach. The approach was verified using a classic diametrically compressed disc. The proposed method solves the problem of quantitative birefringence measurement in planar polariscopes by introducing the phase information. It reduces the PIE scans and shortens the data collection time, which provides a practical measurement means for birefringence in materials, biophysics and opto-mechanical system. [ABSTRACT FROM AUTHOR]

A quantitative contrast enhancement imaging concept for phase retrieval based on the synthetic diffraction patterns was proposed. A virtual specimen could be retrieved by original phase retrieval algorithms using synthetic diffraction patterns which are compounded from the diffraction patterns both with and without original weak phase specimen. Compared to the original specimen, the amplitude and phase contrast of the virtual specimen were distinctly enhanced while the structures were not changed. The conversion relationships between the virtual and actual specimen were theoretically and quantitatively determined. The validity was demonstrated by simulations and practical experiments with extended ptychographic iterative engine and coherent modulation imaging respectively, and the results agree with the conclusions of the theoretical analysis. The proposed concept provides a simple, universal and practical imaging enhancement technique for existing phase retrieval algorithms with different light sources. [ABSTRACT FROM AUTHOR]

High-power laser devices have stringent requirements for the surface accuracy of optical elements. Continuous polishing is an effective technique for polishing high-precision optical elements. To overcome the problem of poor real-time capability and low accuracy in traditional surface shape monitoring and controlling methods used in continuous polishing, an online monitoring device is developed to monitor the surface shape of the polishing pad. The experimental results of the online measurement are highly consistent with the offline results obtained using an interferometer. The correctness and feasibility of the online monitoring scheme are well validated. Based on the online monitoring device for the surface shape of the polishing pad, we propose a method of automatic control for the surface shape of the polishing pad. This method maintains the flatness of the polishing pad to 0.05λ (λ = 632.8 nm), peak to valley, as measured on a 100-mm monitoring element through computer control. [ABSTRACT FROM AUTHOR]

A model is presented to analyze the effect of chromatic aberration of the spatial filter lenses on the compressed pulse duration. The parameters of the SHENGUANG (SG) II 5 PW laser system are demonstrated as examples. The numerical simulation results show that the compressed pulse duration with full aperture is increased by 3 times compared with the ideal compressed pulse duration in the case of chromatic aberration of the lenses. The result of full-aperture measurement at the SG II 5 PW laser system is in good agreement with the theoretical calculation. In the case of full-aperture measurement, the shortest compressed pulse duration is obtained by adjusting the compressor to compensate for the phase aberration introduced by the chromatic aberration of the spatial filter lenses at the SG II 5 PW laser facility. These results are helpful in finding an optimized pulse duration, considering the chromatic aberration of lenses in the femtosecond laser facility, and in obtaining a deep understanding of the effect of chromatic aberration of lenses on the pulse contrast ratio and pulse duration in ultrashort laser systems. [ABSTRACT FROM AUTHOR]

A type of ptychography-based phase microscope was developed by integrating a spatial light modulator (SLM) into a commercial wide-field light microscope. By displaying a moving pattern on the SLM to change the sample illumination and record the diffraction intensities formed, both the modulus and phase of the transmission function of the sample could be accurately reconstructed with formulas similar to those of common ptychography. Compared with other kinds of phase microscopes, the developed microscope has several advantages, including its simple structure, high immunity to coherent noise, and low requirement for quality optics. In addition, defects in the illumination beam are also removed from the reconstructed image. Further, this microscope's fast data acquisition ability makes it highly suitable for many applications where highly accurate quantitative phase imaging is important, such as in living cells or other fragile biological samples that cannot sustain continuous imaging over a long period of time. [ABSTRACT FROM AUTHOR]

The high fluence performance of high-power laser systems is set by optical damage, especially in the final optics assembly (FOA). The flaws on the frequency converter surface can cause optical intensity intensification and, therefore, damage the downstream optical elements, such as the beam sampling grating (BSG), which is an important component in the FOA. Mitigation of BSG damage caused by flaws is discussed. Physical models are established to simulate the optical field enhancement on BSG modulated by the upstream flaw, considering both the linear and nonlinear propagation effects. Numerical calculations suggest that it is important to place the BSG in a properly selected position to mitigate the laser-induced damage. Furthermore, strict controls of flaw size, modulation depth, distance between frequency converter and focusing lens, and the thickness of the focusing lens are also significant to mitigate the BSG damage. The results obtained could also give some suggestions for damage mitigation of optical components and the layout design of the final optics assembly. [ABSTRACT FROM AUTHOR]

The recently developed Light Field Moment Imaging (LMI) is adopted to show the stereoscopic structure of the sample studied in Coherent Diffractive Imaging (CDI), where 3D image were always generated with complicated experimental procedure such as the rotation of the sample and time-consuming computation. The animation of large view angle can be generated with LMI very quickly, and the 3D structure of sample can be shown vividly. This method can find many applications for the coherent diffraction imaging with x-ray and electron beams, where a glimpse of the hierarchical structure required and the quick and simple 3D view of object is sufficient. The feasibility of this method is demonstrated theoretically and experimentally with a recently developed CDI method called Ptychographic Iterative Engine. [ABSTRACT FROM AUTHOR]

Ultrafast reflection and secondary ablation have been theoretically investigated with a Fresnel-Drude model in laser processing of transparent dielectrics with picosecond pulsed laser. The time-dependent refractive index has a crucial effect on the cascade ionization rate and, thereby, on the plasma generation. The relative roles of the plasma gas and the incident angle in the reflection are discussed in the case of the oblique incidence. The angular dependence of the reflectivity on the laser-excited surface for s- and p-polarization is significantly different from the usual Fresnel reflectivity curve in the low-fluence limit. A road map to the secondary ablation induced by the reflected pulse is obtained on the angles of the first and second incidence. It indicates that the laser-induced plasma plays a major role in the secondary ablation, which could overcome the saturation of the ablation crater depth or generate microcracks underneath the crater wall. [ABSTRACT FROM AUTHOR]

Magnetic reconnection is a process by which oppositely directed magnetic field lines passing through a plasma undergo dramatic rearrangement, converting magnetic potential into kinetic energy and heat. It is believed to play an important role in many plasma phenomena including solar flares, star formation and other astrophysical events, laser-driven plasma jets, and fusion plasma instabilities. Because of the large differences of scale between laboratory and astrophysical plasmas, it is often difficult to extrapolate the reconnection phenomena studied in one environment to those observed in the other. In some cases, however, scaling laws do permit reliable connections to made, such as the experimental simulation of interactions between the solar wind and the Earth's magnetosphere. Here we report well-scaled laboratory experiments that reproduce loop-top-like X-ray source emission by reconnection outflows interacting with a solid target. Our experiments exploit the mega-gauss-scale magnetic field generated by interaction of a high-intensity laser with a plasma to reconstruct a magnetic reconnection topology similar to that which occurs in solar flares. We also identify the separatrix and diffusion regions associated with reconnection in which ions become decoupled from electrons on a scale of the ion inertial length. [ABSTRACT FROM AUTHOR]

The development of parametric instabilities in a large scale inhomogeneous plasma with an incident laser beam composed of multiple frequency components is studied theoretically and numerically. Firstly, theoretical analyses of the coupling between two laser beamlets with certain frequency difference δω0 for parametric instabilities is presented. It suggests that the two beamlets will be decoupled when δω0 is larger than certain thresholds, which are derived for stimulated Raman scattering, stimulated Brillouin scattering, and two plasmon decay, respectively. In this case, the parametric instabilities for the two beamlets develop independently and can be controlled at a low level provided the laser intensity for individual beamlet is low enough. Secondly, numerical simulations of parametric instabilities with two or more beamlets (N ∼ 20) have been carried out and the above theory model is validated. Simulations confirm that the development of parametric instabilities with multiple beamlets can be controlled at a low level, provided the threshold conditions for δω0 is satisfied, even though the total laser intensity is as high as ∼1015 W cm−2. With such a laser beam structure of multiple frequency components and total bandwidth of a few percentages (≳4%ω0), the parametric instabilities can be well-controlled. [ABSTRACT FROM AUTHOR]

In a high power laser system, the stress in large-aperture optical component could affect the system beam quality and safe operation. But studies on stress distribution and influence mainly focus on the finite element analysis. A new stress measurement method for large-aperture sample, which combines the ptychography with the polarization measurement technique, is presented. The birefringent sample is placed in the parallel probe-forming path. By the complex amplitude reconstructions of probes carrying stress information under different polarization states, the separation of two principal stress components is realized and quantitative full-field stress information is provided. The theoretical derivation and experimental implementation about how to extract strong stress information from phase are illustrated. The feasibility of this method is verified through a classic diametrically compressed disc, and the result for each stress component agrees well with the theoretical model. The proposed method avoids the scanning movement of sample and has a simple structure and strong anti-interference ability. It can be further combined with single-shot PIE techniques for rapid and online measurement, which provides a practical measurement means for the study of stress in large-aperture optics. [ABSTRACT FROM AUTHOR]

Nuclear fusion reactions are the most important processes in nature to power stars and produce new elements, and lie at the center of the understanding of nucleosynthesis in the universe. It is critically important to study the reactions in full plasma environments that are close to true astrophysical conditions. By using laser-driven counter-streaming collisionless plasmas, the fusion d+d→³He+n is studied in a Gamow-like window around 27 keV. The results give hints that astrophysical nuclear reaction yields can be modulated significantly by the self-generated electromagnetic fields and the collective motion of the plasma. This plasma-version minicollider may provide a novel tool for studies of astrophysics-interested nuclear reactions, as well as a useful tool to constrain the models of plasma colliding dynamic. [ABSTRACT FROM AUTHOR]

A counter-streaming flow system is a test-bed to investigate the astrophysical collisionless shock (CS) formation in the laboratory. Electrostatic/electromagnetic instabilities, competitively growing in the system and exciting the CS formation, are sensitive to the flows parameters. One of the most important parameters is the velocity, determining what kind of instability contributes to the shock formation. Here we successfully measure the evolution of the counter-streaming flows within one shot using a multi-pulses imaging diagnostic technique. With the technique, the average velocity of the high-density-part () of the flow is directly measured to be of cm/s between 7 ns and 17 ns. Meanwhile, the average velocity of the low-density-part () can be estimated as cm/s. The experimental results show that a collisionless shock is formed during the low-density-part of the flow interacting with each other. [ABSTRACT FROM AUTHOR]

Phase matching is a necessary condition for achieving high-efficiency optical-frequency conversion. To date, practical means of accomplishing phase matching in homogeneous crystals remain limited, despite considerable efforts. Herein, we report a new class of methods aimed at achieving quasiperfect phase matching, based on controllable birefringence produced via the linear electro-optic effect, termed "voltage-tuning phase matching." The wave vectors of the induced polarization and the generated fields can be matched and maintained along the direction of propagation by introducing an external electric field. We analyze the validity and feasibility of this method theoretically and demonstrate it experimentally by applying the linear electro-optic effect and fourth-harmonic generation simultaneously in a partially deuterated KH2PO4 crystal. Quasiperfect phase matching is achieved systematically over a temperature range of the initial phase-matching temperature ±2 °C. Moreover, this method can overcome the limitation of the birefringence in traditional technologies and provides new functionalities for conventional nonlinear materials as well as low-birefringence and isotropic materials. This technology may significantly impact the study of optical-frequency conversion and has promise for a broad range of applications in nonlinear optics. [ABSTRACT FROM AUTHOR]

The influence of partial coherence on the image reconstruction in ptychography is analyzed, and a simple method is proposed to reconstruct a clear image for the weakly scattering object with partially coherent illumination. It is demonstrated numerically and experimentally that by illuminating a weakly scattering object with a divergent radiation beam, and doing the reconstruction only from the bright-field diffraction data, the mathematical ambiguity and corresponding reconstruction errors related to the partial coherency can be remarkably suppressed, thus clear reconstructed images can be generated even under seriously incoherent illumination. [ABSTRACT FROM AUTHOR]

Herbig–Haro (HH) objects associated with newly born stars are typically characterized by two high Mach number jets ejected in opposite directions. However, HH 110 appears to only have a single jet instead of two. Recently, Kajdi et al. measured the proper motions of knots in the whole system and noted that HH 110 is a continuation of the nearby HH 270. It has been proved that the HH 270 collides with the surrounding mediums and is deflected by 58°, reshaping itself as HH 110. Although the scales of the astrophysical objects are very different from the plasmas created in the laboratory, similarity criteria of physical processes allow us to simulate the jet deflection in the HH 110/270 system in the laboratory with high power lasers. A controllable and repeatable laboratory experiment could give us insight into the deflection behavior. Here we show a well downscaled experiment in which a laser-produced supersonic-jet is deflected by 55° when colliding with a nearby orthogonal side-flow. We also present a two-dimensional hydrodynamic simulation with the Euler program, LARED-S, to reproduce the deflection. Both are in good agreement. Our results show that the large deflection angle formed in the HH 110/270 system is probably due to the ram pressure from a flow–flow collision model. [ABSTRACT FROM AUTHOR]

Magnetic reconnection experiments in high-energy-density (HED) laser-produced plasmas have recently been conducted at the Shenguang-II (SG-II) facility. Two plasma bubbles and a ‘frozen-in’ magnetic field are generated by irradiating an Al foil using two laser beams. As the two bubbles with opposing magnetic fields expand and squeeze each other, magnetic reconnection occurs. In the experiments, three well-collimated high-speed electron jets are observed in the fanlike outflow region of the laser-driven magnetic reconnection. Based on two-dimensional (2D) particle-in-cell (PIC) simulations, we demonstrate that the three electron jets in the outflow region of laser-driven magnetic reconnection are super-Alfvénic, and their formation mechanism is also revealed in this paper. The two super-Alfvénic jets at the edge are formed by the outflow electrons, which move along magnetic field lines after they are accelerated in the vicinity of the X-line by the reconnection electric field. The super-Alfvénic jet at the center is formed by the electrons that come from the outside of the plasma bubbles. These electrons are reflected by the magnetic field in the pileup region and are meanwhile accelerated by the resulting electric field. [ABSTRACT FROM AUTHOR]