There are extremely luminous quasi stellar objects (QSOs) at high redshift which are absent at low redshift. The lower luminosities at low redshifts can be understood as the external manifestation of either a lower Eddington ratio or a lower mass. To distinguish between both effects, we determine the possible dependence of masses and Eddington

The molar extinction coefficients, known also as molar absorptivity epsilon, of C-60 and C-70 fullerenes infrared absorption spectra were determined at room temperature on samples embedded in KBr pellets. Furthermore, the integrated molar absorptivity Psi of each absorption infrared band either of C-60 and of C-70 was measured and reported together

Aims: We study the ionized gas emission from the large scale shock region of Stephan's Quintet (SQ). Methods: We carried out integral field unit (IFU) optical spectroscopy on three pointings in and near the SQ shock. We used Potsdam MultiAperture Spectrometer (PMAS) on the 3.5 m Calar Alto telescope to obtain measures of emission lines that provide

We present near-infrared spectra of 23 B-type asteroids obtained with the NICS camera-spectrograph at the 3.56 m Telescopio Nazionale Galileo. We also compile additional visible and near-infrared spectra of another 22 B-type asteroids from the literature. A total of 45 B-types are analyzed. No significant trends in orbital properties of our sample

The characterization of the atomic and molecular hydrogen content of high-redshift galaxies is a major observational challenge that will be addressed over the coming years with a new generation of radio telescopes. We investigate this important issue by considering the states of hydrogen across a range of structures within high-resolution

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