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[en] The discharge characteristics of a new combined low energy magnetron-ion-source sputtering system are presented. The ignition curves, current-voltage characteristics of the system in dependence on gas pressure, magnitude and topology of magnetic field have been researched both for autonomous operation of the planar magnetron discharge and Hall type ion source in plasma mode and for their combination. Spatial distributions of ion current are also presented. (author)
[en] The transport characteristics of a space charge-dominated multi-species deuterium beam consisting of , , and particles in an electrostatic low-energy beam line are studied. First, the envelope equations of the primary beam are derived considering the space charge effects caused by all particles. Second, the evolution of the envelope of the multi-species deuterium beam is simulated using the PIC code TRACK, with the results showing a significant effect of the unwanted beam on the transport of the primary beam. Finally, different injected beam parameters are used to study beam matching, and a new beam extraction system for the existing duoplasmatron source is designed to obtain the ideal injected beam parameters that allow a beam of up to 50 mA to pass unobstructed through the electrostatic low-energy beam transport line in the presence of an unwanted (, ) beam of 20 mA; at the same time, distortions of the beam emittance and particle distributions are observed.
[en] Highlights: • This is the first time that a MXRL was used in the TXRF without using slit. • The divergence of the X-ray beam emitted from the MXRL is sufficiently low to meet the requirements of the TXRL. • Due to the micro focal spot of the incident X-ray beam and confocal technology, this new TXRF instrument will be widely used in the field of microscopic analysis, which will help improve the processing technology. - Abstract: A total reflection X-ray fluorescence (TXRF) spectrometer based on an elliptical monocapillary X-ray lens (MXRL) and a parallel polycapillary X-ray lens (PPXRL) was designed. This TXRF instrument has micro focal spot, low divergence and high intensity of incident X-ray beam. The diameter of the focal spot of MXRL was 16.5 µm, and the divergence of the incident X-ray beam was 3.4 mrad. We applied this TXRF instrument to the micro analysis of a single-layer film containing Ni deposited on a Si substrate by metal vapor vacuum arc ion source.
[en] The cryogenic Penning Ion trap (PIT) facility at VECC has a specially designed cryostat where the trap along with its detection electronics will remain immersed in the liquid helium filled bore of a 5T superconducting cryomagnet dewar. Detailed descriptions of the magnet and mechanical assembly for immersing the trap assembly were described
[en] Discovery of LASER has a profound impact on almost every field of science and technology and related applied research. With advancement of various mode locking techniques it could be possible to generate short duration laser pulses which has eventually brought down in the femtosecond (ultra-short) regime. Using Chirped Pulse Amplification (CPA) technique, proposed by G. Mourou and D. Strickland (Awarded Nobel Prize in Physics, 2018), it has now been possible to develop high-power, several Terawatt (TW) to few Petawatt (PW) level, ultra-short pulse duration laser systems. In CPA technique an ultra-short duration laser pulse from oscillator is first temporally stretched and after desired level of amplification in various amplifier stages is compressed back to the ultra-short duration. Availability of high-power, ultra-short lasers has dramatically changed the physics and applications of high-intensity laser-plasma interaction, a subject of extensive research during laser several decades. In the earlier studies high-power lasers with few nanoseconds to hundreds of picosecond pulse duration were used, primarily due to its relevance to laser-driven inertial confinement fusion. Whereas, using high-power, ultrashort duration laser pulses, focused to a focal spot of several microns diameter, laser intensities in the range of ∼1018 Wcm-2 to greater than 1020 Wcm-2 could be achieved. Laser plasma interaction at such ultra-high intensities could drive giant electron plasma wave (termed here as Tsunami in the plasma) which could be used for accelerating electrons to high-energies (several tens of MeV to few GeV) in a small interaction length of few mm to few cms. Such compact accelerators could also be used to develop laser driven synchrotron (x-rays and γ-rays) sources. In this talk, I shall present a brief overview of this exciting area of advanced laser driven acceleration technique, and recent experimental investigations performed at APAS, LPD, RRCAT, Indore. (author)
[en] The structure design of RF ion source driving source and the heat flow and solid coupling analysis of RF coils were introduced. RF ion source is produced by the external antenna inductive coupling. Using design of dual RF driving source, each RF driving source power is about 60 kW, and the total RF ion source power is 120 kW, which can produce uniform high-density plasma to meet the stability requirements of long pulse operation. Upon completion of the above work, the RF ion source prototype assembly and preliminary test were completed. (authors)
[en] Laser pulse shape effect has been considered to estimate the self-generated magnetic field in laser-plasma interaction. A ponderomotive force based physical mechanism has been proposed to investigate the self-generated magnetic field for different spatial profiles of the laser pulse in inhomogeneous plasmas. The spatially inhomogeneous electric field of a laser pulse imparts a stronger ponderomotive force on plasma electrons. Thus, the stronger ponderomotive force associated with the asymmetric laser pulse generates a stronger magnetic field in comparison to the case of a symmetric laser pulse. Scaling laws for magnetic field strength with the laser and plasma parameters for different shape of the pulse have been suggested. Present study might be helpful to understand the plasma dynamics relevant to the particle trapping and injection in laser-plasma accelerators. (author)
[en] The characterization of ion beam current density distribution and beam uniformity is crucial for improving broad-beam ion source technologies. The design of the broad ion beam extraction system directly affects these two parameters, therefore, depending on the application, the design and geometry of the source is changed. In this study, the effect of the presence or the absence of a neutralization process on the ion beam density was investigated. Also, the effect of the probe bias on the ion beam current measurement was evaluated. Eventually, using a flat probe, the ion beam profiles obtained from the extraction system of the ion source (Model RFIS 60, ACECR, Iran) were measured at energies from 300 eV to 1000 eV and compared in terms of current and uniformity of the ion beam in the absence of the neutralizer. In these experiments, screen and accelerator grids with different geometries (flat and convex grids) were used for comparison purposes. According to the obtained results, the flat grids generate a higher current density while the convex grids generate a more uniform beam. Therefore, each of these grid geometries can be suitable depending on the desired application.
[en] This symposium covers frontline research in basic laser physics, as well as significant advances made in the development and applications of lasers in nuclear science and technology, defence, aerospace, bio-medical, industry etc. The topics covered in this symposium are: physics and technology of lasers, laser materials and non linear processes, ultrafast lasers and applications, laser materials, devices and components, lasers in nuclear science and technology, laser applications in chemistry, biology and medicine, laser applications in material science and laser spectroscopy. Papers relevant to INIS are indexed separately