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We present extreme ultraviolet laboratory spectra of highly charged S IX and S X measured using a compact electron beam ion trap. The data were recorded using a flat-field grazing incidence spectrometer in the wavelength range between 210 and 290 Å. The beam energy was tuned for three different values at 365, 410 and 465 eV while keeping electron beam current constant at 10 mA. By measuring the beam energy dependence, we identified several lines originating from S IX and S X ions with the support of collisional-radiative modeling. We compared them with the present calculations and transitions listed in the NIST data base and found in good agreement. [ABSTRACT FROM AUTHOR]

We performed high resolution extreme ultraviolet (EUV) spectroscopy measurements of highly charged xenon ions with a compact electron beam ion trap. The spectra were recorded with a flat-field grazing incidence spectrometer while varying the electron beam energy between 200 and 890 eV. We measured the wavelengths for several lines of Rh-like Xe 9+ - Cd-like Xe 6+ and Cu-like Xe 25+ - Se-like Xe 20+ in the range of 150–200 Å with an uncertainty of 0.05 Å. Previously, most of these lines have been reported from EBITs with a wavelength uncertainty of 0.2 Å. Additionally, based on the electron beam energy dependence of the observed spectra we tentatively identified three new lines, which were reported as unidentified lines in the previous studies. [ABSTRACT FROM AUTHOR]

We report high-resolution density dependent intensity ratio measurements for middle charge states of iron in the extreme ultraviolet (EUV) spectral wavelength range of 160-200 Å. The measurements were performed at the Tokyo EBIT laboratory by employing a flat-field grazing incidence spectrometer installed on a low energy compact electron beam ion trap. The intensity ratios for several line pairs stemming from Fe X, Fe XI and Fe XII were extracted from spectra collected at the electron beam energies of 340 and 400 eV by varying the beam current between 7.5 and 12 mA at each energy. In addition, the effective electron densities were obtained experimentally by imaging the electron beam profile and ion cloud size with a pinhole camera and visible spectrometer, respectively. In this paper, the experimental results are compared with previous data from the literature and with the present calculations performed using a collisional-radiative model. Our experimental results show a rather good agreement with the calculations and previous reported results. [ABSTRACT FROM AUTHOR]

Intensity ratio of density sensitive emission lines emitted from Fe ions in the extreme ultraviolet region is important for astrophysics applications. We report high-resolution intensity ratio measurements for Fe ions performed at Tokyo EBIT laboratory by employing a flat-field grazing incidence spectrometer. The experimental intensity ratios of Fe X and Fe XII are plotted as a function of electron density for different electron beam currents. The experimental results are compared with the predicted intensity ratios from the model calculations. [ABSTRACT FROM AUTHOR]