The density and composition of the Martian atmosphere allow solar ultraviolet photons with wavelengths as short as 190 nm to reach the surface. We investigate the hypothesis that this UV radiation is capable of inducing the release of water from iron oxyhydroxide minerals resulting in the formation of oxide phases. These experiments, which utilize a quadrupole mass spectrometer to monitor the w...

2.1.1. Ultraviolet lasers The ultraviolet laser systems used in the experiments described in Chapter 3 and listed in Table 3.1, covered a broad range of wavelengths and pulse durations. They included a seeded single-mode Nd:YAG laser, a nitrogen laser, and a Ti:sapphire ultrafast laser system. Nanosecond-duration pulses at 266 nm were generated using non-linear crystals to frequencyquadruple th...

The new high effiency extreme ultraviolet overview spectrometer (HEXOS) system for the stellarator Wendelstein 7-X is now mounted for testing and adjustment at the tokamak experiment for technology oriented research (TEXTOR). One part of the testing phase was the intensity calibration of the two double spectrometers which in total cover a spectral range from 2.5 to 160.0 nm with overlap. This w...

We investigate the effect of using three different cross section data sets on ozone profile retrievals from Global Ozone Monitoring Experiment (GOME) ultraviolet measurements (289–307 nm, 326–337 nm). These include Bass-Paur, Brion, and GOME flight model cross sections (references below). Using different cross sections can significantly affect the retrievals, by up to 12 Dobson Units (DU, 1 DU=...

Increase in the population demands healthy food, clean air, fresh water and high secured life. To fulfil above demands, spectrometers such as ultraviolet, Fourier transformation infrared, Raman, HPLC, gas chromatography are used confirmation tool for identification of materials. The cost space above-mentioned instruments more to build low-cost spectrometer with efficiency is a challenging resea...

Optical frequency combs offer enormous potential in the detection and control of atoms and molecules by combining their vast spectral coverage with the extremely high spectral resolution of each individual comb component. Sensitive and multiplexed trace gas detection via cavity-enhanced direct frequency comb spectroscopy has been demonstrated for various molecules and applications; however, pre...

Abstract Accurate measurements of electron density are critical for determination the plasma properties in solar corona. We compare densities diagnosed from Fe xiii lines observed by Extreme-Ultraviolet Imaging Spectrometer (EIS) onboard Hinode mission with near-infrared (NIR) provided ground-based Coronal Multichannel Polarimeter (CoMP). To do that, emissivity-ratio method based on all availab...

One of the keys to interpreting the character and evolution of interstellar matter in the galaxy is understanding the distribution of the low density hot (10 5 K − 10 6 K) phase of the interstellar medium (ISM). This phase is much more difficult to observe than the cooler high density components of the ISM because of its low density and lack of easily observable tracers. Because gas of this tem...