Ultraviolet Absorption Spectroscopy

Ultraviolet Quasar Absorption Line Spectroscopy of z ∼ 1 Galaxy Group

We used ultraviolet spectra from HST/STIS (R = 30, 000), together with optical spectra from Keck/HIRES (R = 45, 000), to study the three MgII-selected absorption systems at z = 0.9254, 0.9276, and 0.9342 toward the quasar PG 1206 + 459. A multi-phase gaseous structure, with low-ionization components produced in small condensations and high-ionization ones in diffuse clouds, is indicated in all ...

X-ray Spectroscopy of QSOs with Broad Ultraviolet Absorption Lines

For the population of QSOs with broad ultraviolet absorption lines, we are just beginning to accumulate X-ray observations with enough counts for spectral analysis at CCD resolution. From a sample of eight QSOs [including four Broad Absorption Line (BAL) QSOs and three mini-BAL QSOs] with ASCA or Chandra spectra with more than 200 counts, general patterns are emerging. Their power-law X-ray con...

Ultraviolet absorption in lenses.

Jovian Atmosphere: Near-Ultraviolet Absorption

Greenspan and Owen (1), in a stimulating discussion of the Jovian atmosphere, have reconsidered Stecher's (2) rocket ultraviolet spectroscopy of Jupiter. They conclude that, while the general reflectivity between 2000 and 3000 A can be matched by some 12 km-atm of H2 and a small surface reflectivity, there still exist two significant absorption features in this wavelength range. This residual a...

Ionization and dissociation dynamics of vinyl bromide probed by femtosecond extreme ultraviolet transient absorption spectroscopy.

Strong-field induced ionization and dissociation dynamics of vinyl bromide, CH2=CHBr, are probed using femtosecond extreme ultraviolet (XUV) transient absorption spectroscopy. Strong-field ionization is initiated with an intense femtosecond, near infrared (NIR, 775 nm) laser field. Femtosecond XUV pulses covering the photon energy range of 50-72 eV probe the subsequent dynamics by measuring the...