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An electron spectrometer was used to measure the electron and ion spectra in two different irradiations of implosion laser to the deuterated spherical shell targets at the direct fast ignition experiments on the Gekko-LFEX facility. In the transverse irradiation against the LFEX laser axis, the low effective hot electron temperature (Teff) and huge neutron yield (Ny) could be obtained although high Teff and low Ny could be observed in the axial irradiation. In the transverse irradiation, the efficient core heating could be obtained because the laser-plasma interaction position is close to the core and the diffusive/ion drag heating may be effective., source:https://doi.org/10.1585/pfr.16.2404076

The Moon has no global dipole magnetic field. According to the observations so far made by lunar orbiting spacecraft, there are crustal magnetic anomalies on the lunar surface. If the locations of the magnetic anomalies with the size of a few km to 10 km coincide with the rills on the lunar surface, the magnetic anomalies are probably due to the thermo-remnant magnetism. Furthermore, there is a possibility that the direction and the estimated age of the anomalies are consistent with the existence of the global dipole magnetic field in ancient times. An electro-static analyzer ESA (Electron Spectrum Analyzer) onboard the SELENE satellite has been developed in order to observe the magnetic anomalies by electron reflection method. With the existence of the remnant magnetic field on the lunar surface, the electron moving toward the moon with large pitch angle around the ambient magnetic field will be reflected back to the satellite by a magnetic mirror. By measuring the pitch angle distribution of the reflected electrons, the remnant magnetic field on the lunar surface can be deduced. Since SELENE satellite is a three-axis attitude controlled satellite, two sensors mounted on the moonward and the anti-moonward spacecraft panels are needed in order to obtain three-dimensional electron distribution function. The ESA sensor basically employs a method of a top-hat type electrostatic analyzer placing angular scanning deflectors at the entrance and toroidal deflectors inside. The Field Of View (FOV) is electrically scanned between +/- 45 degrees around the center of the FOV that is 45 degrees inclined from the axis of symmetry. In order to decide the sensitivity of ESA, the averaged count rate of ESA has been estimated using the electron flux data obtained by Electron Reflectometer (ER) onboard the Lunar Prospector (LP) satellite. LP is a lunar orbiter launched on Jan 6, 1998 by NASA. In order to evaluate the manufacturing and assembling error of ESA, the characteristics of E, 現在月はグローバルなダイポール磁場を持たないことが知られている。しかし過去の観測から月表面には磁気異常が存在することが解っている。もし月溶岩地形に関係した数kmから10km程度の磁気異常が多々見つかれば、それはおそらく熱残留磁化起源であり、月表面の地形依存した磁気異常モーメントの方向と年代が、推測される古月グローバル磁場と矛盾が無ければ、溶岩形成当時の月グローバル磁場の存在を強く示唆する。電子反射法によって磁気異常を観測するため、SELENE衛星搭載用電子エネルギー分析器(ESA: Electron Spectrum Analyzer)の開発を行なった。電子反射法とはSELENE衛星に搭載される磁力計LMAG(Lunar MAGnetometer)と同時に観測を行い、太陽風の電子が月表面の磁場によって反射されることで生じる電子のピッチ角異方性を利用して月表面磁場を求める方法である。SELENE衛星は3軸姿勢制御衛星であるためスピンしない。そのため月面側に1台、反月面側に1台の計2台のESAで4πの視野を持たせることにした。ESAは基本的にはTop-Hat型の静電分析器であるが、荷電粒子の入射口に45度方向を中心に±45度の掃引を行なう視野角掃引電極を置くことで2πの視野を持つことができる。分析器の開発に際しては、1998年にNASAにより打ち上げられた月周回衛星であるLunar Prospectorのデータを用いて、月周回軌道上で取得が予想される電子のカウント数を推定し、2台の衛星搭載用ESAの感度を決定した。さらに数値計算によるESAの特性と較正実験結果を比較することで、新規開発要素である視野角掃引電極の性能とセンサーの加工精度、組み上げ精度に問題が無い事を確認した。月溶岩地形に依存した数kmから10km程度の磁気異常を測定するためには、測定エネルギー、角度分解能、時間分解能などの運用モードを適切に選択する必要がある。そこでtest particleシミュレーションを行なうことで適切な運用モードを特定し、10km程度の磁気異常を世界最高レベルの時間分解能1秒で観測できることを示した。, JAXA Research and Development Report, 宇宙航空研究開発機構研究開発報告

У тези су приказани резултати истраживања атома индијума користећи електронску и оптичку спектроскопију. Објашњене су обе експерименталне технике укључујући и поставке експеримента. Електронским спектрометром су мерени диференцијални и интегрисани пресеци за еластично и нееластично расејање електрона на атому индијума. Мерења су урађена за упадне енергије Е0 = 10, 20, 40, 60, 80 и 100еV. Еластично расејање је мерено на великим угловима од 10о до 150о са кораком 10о и извршено је поређење са теоријским методом оптичких потенцијала. Диференцијални пресеци за електронску ексцитацију резонантног стања 6s 2S1/2 атома индијума мерени су на малим и великим угловима. Функција расејања унапред је коришћена за нормирање генералисаних јачина осцилатора (ГОС) на оптитичку јачину осцилатора и добијање апсолутних вредности диференцијалних пресека. Оптички спектри In I и In II линија снимљени су стрик камером. Приказано је поређење оптичких спектара добијених техником ласерски индукованог пробоја са спектрима губитака енергије електрона који су добијени коришћењем електронске спектроскопије., Experimental study of indium atom using electron and optical spectroscopy is presented in thesis. Described are both experimental techniques including experimental setups. Differential and integrated cross sections on elastic and inelastic electron scattering by indium atom are measured using electron spectrometer. The measurements are performed at incident electron energies of E0 = 10, 20, 40, 60, 80 and 100 eV within the large scattering angles ranging from 10o to 150o in steps of 10o. The experimental results are presented and comparison with the values predicted by calculated optical potentials method is conducted, showing good agreement. The differential cross sections (DCSs) for electron-impact excitation of the resonant state 6s 2S1/2 of Indium atom are measured at small and large angles. The forward scattering function method has been used for normalizing the generalized oscillator strengths (GOS) to the known optical oscillator strength and obtaining the absolute DCS values. Optical spectrum of In I and In II lines has been acquired by a streak camera. The experimental results regarding indium lines obtained by laser induced breakdown spectroscopy (LIBS) have been compared to the energy loss spectra obtained using electron spectroscopy.

A new energy and angle resolved analyzer for photoelectron spectroscopy is described. This analyzer is based on combining an advanced focusing electron lens system with time-of-flight measurements. A position sensitive detector gives time and position for the electron events. From this information the kinetic energy and start direction are obtained through a transformation procedure, giving both a large luminosity and a very high energy resolution. The instrument analyses the angles of emission of the electrons in a cone with 30 degrees opening angle and simulations show that extremely high energy and angular resolution can be achieved simultaneously. We report the first results from this instrument, obtained at the PM-3 beam line at BESSY (Berlin, Germany). This analyzer opens up new possibilities for angular resolved electron spectroscopy, band-mapping and other applications.

A spectrometer has been developed to measure relativistic electrons produced in di®erent types of plasmas, like: tokamak plasmas, laser produced plasmas. The spectrometer consists of 9 YSO (Y2SiO5 : Ce) crystals, which are shielded by stainless steel ¯lters. The absolute calibration of the spectrometer was performed at the superconducting electron linear accelerator ELBE. The spectrometer can provide information about energy distribution of electrons and their numbers for the energy range between 4 and 30 MeV. The spectrum is analyzed by means of the Monte Carlo 3D Geant4 code.

The Combined Release and Radiation Effects Satellite (CRRES) payload included a number of instruments designed to provide data on particles, fields, and waves. The Time History Data Base (THDB) for the CRRES mission provides the data source for short time duration event studies as well as long term efforts involving statistical analyses and modelling efforts. Prime uses for the THDB include the development of the static radiation belt model and cosmic ray model. This study defines the analysis procedures and the instrument THDB file formats for each experiment.