An inverse photoemission spectroscopy (IPES) apparatus using a Czerny-Turner grating spectrometer is demonstrated. Previous IPES instruments based on grating spectrometers used a concave grating and operated in the vacuum ultraviolet range. The reflectance of such gratings is lower than 20% and the aberration cannot be finely corrected leading to an energy resolution of up to 0.1 eV. In the pre...

We have obtained EUV spectra between 90 and 255 8 of the comets C/2002 T7 (LINEAR), C/2001 Q4 (NEAT), and C/2004 Q2 (Machholz) near their perihelion passages in 2004 with the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS). We obtained contemporaneous data on NEAT with the Chandra ACIS instrument, marking the first simultaneous EUVandX-ray spectral observations of a comet. The total CHIPS/E...

A computer model of an Extreme Ultraviolet (EUV) spectrometer based on a gas ionization chamber and on flight experience of the Optics Free Spectrometer (OFS previously flown), was built and tested with the SIMulation of IONs (SIMION) tools. Our goal in this work was to design an improved and simplified electron beam focusing system which fits the dimensions (D = 180 mm; L = 380 mm) available f...

We describe a new compact acousto-optically Q-switched diode-pumped solid-state (DPSS) intracavity frequency-tripled neodymium-doped yttrium vanadate laser capable of producing ~100 mW of 213 nm power quasi-continuous wave as 15 ns pulses at a 30 kHz repetition rate. We use this new laser in a prototype of a deep ultraviolet (UV) Raman standoff spectrometer. We use a novel high-throughput, high...

Four Lyman a airglow measurements of the limb and disc of Mars, made by ultraviolet spectrometers on Mariner 6 and 7 in 1969 and Mariner 9 in 1971, are analyzed to determine the amount and distribution of atomic hydrogen above 80 km. The variation of atomic hydrogen with altitude is calculated by using time-independent chemical diffusion models from 80 to 250 km, and tin exospheric model is use...

We re-examine Voyager Ultraviolet Spectrograph data used to establish upper limits to the λ 500–900 Å and λ 900–1100 Å cosmic diffuse background. The measurement of diffuse flux with the Voyager UVS data requires complex corrections for noise sources which are far larger than the astronomical signal. In the analyses carried out to date, the upper limits obtained on the diffuse background show s...

We have developed an on-the-fly scanning spectrometer operating in the UV-visible and near-infrared that can simultaneously perform transmission and total reflectance measurements at the rate better than 1 sample per second. High throughput optical characterization is important for screening functional materials for a variety of new applications. We demonstrate the utility of the instrument for...

The characteristic electron densities, temperatures, and thermal distributions of 1 MK active region loops are now fairly well established, but their coronal magnetic field strengths remain undetermined. Here we present measurements from a sample observed by the Extreme-ultraviolet Imaging Spectrometer on Hinode. We use recently developed diagnostic technique that involves atomic radiation mode...

Introduction: Europa is unique among the icy galilean satellites, in that it is the one (with the exception of Io) that displays indications of recent or current surface activity. These indications include lineaments, triple bands, wedges, icebergs, as well as pits, spots and domes (e.g. [1], [2]). These regions of recent endogenic activity have been found to correlate with Galileo Near Infrare...