720 XTF Search Results (expand=subject;f1-subject=Galaxy;f2-spectral-Type=Ultraviolet);f1-subject%3DGalaxy;f2-spectral-Type%3DUltraviolet Results for your query: expand=subject;f1-subject=Galaxy;f2-spectral-Type=Ultraviolet Thu, 01 Jan 1970 12:00:00 GMT Cosmic Origins Spectrograph Average Spectrum of 22 AGNs (Active Galactic Nuclei). The spectra were shifted to appear as if they were not redshifted before being averaged. All the objects have spectra that look like quasi-stellar objects, but some are of low enough luminosity that the host galaxy is visible and has a name. The main features of the spectrum are as follows: a purple/blue line drawn through the spectrum is the "continuum," mostly due to the AGN, a continuous glow caused by a very hot gas in a strong magnetic field; a red line represents the fitted spectrum of emission lines, thought to arise in a disk that surrounds the central black hole of the AGN. (These are most clear at the right end.) The ions that are seen in emission are labelled: N V, C IV, He II etc. The Roman numeral is the charge of the ion plus one: N V is four-times ionized oxygen, meaning that four electrons have been stripped off the atom. The ion has a net charge of positive four. The black line traces the actual data. Below about 950 Å, neutral hydrogen absorption lines from the intergalactic medium exist in ... Thu, 01 Jan 1970 12:00:00 GMT